feat: add booking agent session orchestration

2026-08-02 18:32:27 +08:00 · 2026-08-02 18:32:27 +08:00 · 3c000654d8
commit 3c000654d8
parent 77c6d6923b
35 changed files with 3275 additions and 1 deletions
--- a/README.md
+++ b/README.md
@ -135,6 +135,12 @@ curl http://localhost:8080/api/store/list
   ```
   脚本仅为仍为 `pending` 的历史留资建立开放任务，并写入低敏 `follow_up_created` 事实；不会猜测已发送、已取消或已退订线索的处理结果。末尾五项客户归属、状态机、开放任务唯一性和事件完整性验证必须全部为 0。

+12. **智能预约 M0 短期会话**：回访任务迁移验证完成后、部署包含 `BookingAgentSession` 的 backend 前执行：
+   ```bash
+   mysql -h <host> -u <user> -p petstore < db/migrations/20260802_create_booking_agent_session.sql
+   ```
+   脚本只建立短期结构化草稿会话，不保存原文、音频或模型响应，也不关联 `Appointment`。末尾四项状态、唯一键和 TTL 验证必须全部为 0；迁移后仍保持 `PETSTORE_BOOKING_AGENT_ENABLED=false`，生产开启需另行授权。
+
 ### production profile

 ```bash
@ -150,7 +156,7 @@ production profile 下：

 ### 生产只读预检

-完成备份和八个迁移后，以最终生产环境变量运行：
+完成备份和九个版本化迁移后，以最终生产环境变量运行：

 ```bash
 chmod +x deploy/release-preflight.sh deploy/production-smoke.sh
@ -219,6 +225,7 @@ API_ORIGIN=https://<api-domain> backend/deploy/production-smoke.sh
 - [ ] 已执行 `20260802_create_store_onboarding.sql`，历史开通状态与六项邀请/回执验证均为 0
 - [ ] 已执行 `20260802_create_store_customer_timeline.sql`，两项 StoreCustomer 别名不变量均为 0
 - [ ] 已执行 `20260802_create_follow_up_task.sql`，五项回访任务与事件验证计数均为 0
+- [ ] 部署包含智能预约实体前已执行 `20260802_create_booking_agent_session.sql`，四项会话状态与 TTL 验证计数均为 0，功能开关保持关闭
 - [ ] `CORS_ALLOWED_ORIGINS` 仅包含本次发布的显式 HTTPS Web 源
 - [ ] `deploy/release-preflight.sh` 已以最终环境变量通过并留存输出
 - [ ] readiness 与上线后只读冒烟全部通过
--- a/db/migrations/20260802_create_booking_agent_session.sql
+++ b/db/migrations/20260802_create_booking_agent_session.sql
@ -0,0 +1,52 @@
+-- Petstore 智能预约助手 M0：短期会话、草稿版本和固定 TTL
+-- 前置：20260802_create_follow_up_task.sql 已执行。
+-- 本表不保存当轮原文、原始语音、提示词、模型响应或 Appointment 关联。
+
+CREATE TABLE t_booking_agent_session (
+    id BIGINT NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    session_id VARCHAR(36) NOT NULL,
+    customer_user_id BIGINT NOT NULL,
+    store_id BIGINT NOT NULL,
+    status VARCHAR(24) NOT NULL COMMENT 'collecting | proposing | confirmable | fallback | expired | cancelled',
+    draft_json TEXT NOT NULL,
+    draft_version INT NOT NULL DEFAULT 0,
+    entry_source VARCHAR(32) NOT NULL,
+    input_modality VARCHAR(16) NULL COMMENT 'text | voice | mixed；首次成功消息后派生',
+    expires_at DATETIME NOT NULL,
+    create_time DATETIME NOT NULL,
+    update_time DATETIME NOT NULL,
+    CONSTRAINT uk_booking_agent_session_public_id UNIQUE (session_id),
+    CONSTRAINT chk_booking_agent_session_status CHECK (
+        status IN ('collecting', 'proposing', 'confirmable', 'fallback', 'expired', 'cancelled')
+    ),
+    CONSTRAINT chk_booking_agent_input_modality CHECK (
+        input_modality IS NULL OR input_modality IN ('text', 'voice', 'mixed')
+    ),
+    INDEX idx_booking_agent_customer_status_expire (customer_user_id, status, expires_at),
+    INDEX idx_booking_agent_status_expire (status, expires_at)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='智能预约 M0 短期结构化草稿会话';
+
+-- 验证：以下四项在上线迁移完成且清理任务正常后必须全部为 0。
+SELECT COUNT(*) AS invalid_booking_agent_state_count
+FROM t_booking_agent_session
+WHERE status NOT IN ('collecting', 'proposing', 'confirmable', 'fallback', 'expired', 'cancelled')
+   OR draft_version < 0
+   OR entry_source <> 'appointment_create'
+   OR (input_modality IS NOT NULL AND input_modality NOT IN ('text', 'voice', 'mixed'));
+
+SELECT COUNT(*) AS duplicate_booking_agent_public_id_count
+FROM (
+    SELECT session_id
+    FROM t_booking_agent_session
+    GROUP BY session_id
+    HAVING COUNT(*) > 1
+) duplicated;
+
+SELECT COUNT(*) AS invalid_booking_agent_ttl_count
+FROM t_booking_agent_session
+WHERE expires_at <= create_time;
+
+SELECT COUNT(*) AS stale_active_booking_agent_session_count
+FROM t_booking_agent_session
+WHERE status IN ('collecting', 'proposing', 'confirmable')
+  AND expires_at <= NOW();
--- a/db/migrations/README.md
+++ b/db/migrations/README.md
@ -24,4 +24,6 @@

 `20260802_create_follow_up_task.sql` 必须在客户时间线迁移之后执行：建立可领取、改期、关闭和真实再次预约归因的 `t_follow_up_task`。只为仍待处理的历史留资建立开放任务，不猜测其他历史结果；脚本末尾五个验证计数必须为 0。

+`20260802_create_booking_agent_session.sql` 必须在回访任务迁移之后、部署包含智能预约 JPA 实体的 backend 之前执行：建立不含原文/音频/模型响应的短期结构化草稿会话，冻结六态、owner/store 范围、草稿版本和 TTL 索引。脚本末尾四个验证计数必须为 0；功能开关仍保持关闭，迁移本身不代表允许生产调用供应商。
+
 正式迁移框架仍属于 Phase 0 后续任务；接入前不得把本目录误当成自动执行目录。
--- a/src/main/java/com/petstore/bookingagent/api/BookingAgentController.java
+++ b/src/main/java/com/petstore/bookingagent/api/BookingAgentController.java
@ -0,0 +1,137 @@
+package com.petstore.bookingagent.api;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.petstore.auth.CurrentUser;
+import com.petstore.auth.CurrentUserContext;
+import com.petstore.bookingagent.service.BookingAgentAudioValidator;
+import com.petstore.bookingagent.service.BookingAgentException;
+import com.petstore.bookingagent.service.BookingAgentService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.web.bind.MissingServletRequestParameterException;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.multipart.MultipartException;
+import org.springframework.web.multipart.MultipartFile;
+import org.springframework.web.multipart.support.MissingServletRequestPartException;
+
+import java.io.IOException;
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+@RestController
+@RequestMapping("/api/booking-agent")
+@RequiredArgsConstructor
+public class BookingAgentController {
+    private final BookingAgentService bookingAgentService;
+    private final BookingAgentRequestParser requestParser;
+
+    @PostMapping("/sessions")
+    public Map<String, Object> createSession(@RequestBody JsonNode body) {
+        CurrentUser user = requireCustomer();
+        Long storeId = requestParser.parseCreateSession(body);
+        return success(bookingAgentService.createSession(user.userId(), storeId));
+    }
+
+    @PostMapping("/sessions/{sessionId}/messages")
+    public Map<String, Object> submitMessage(
+            @PathVariable String sessionId,
+            @RequestBody JsonNode body) {
+        CurrentUser user = requireCustomer();
+        BookingAgentRequestParser.SubmitMessageCommand command = requestParser.parseMessage(body);
+        return success(bookingAgentService.submitMessage(
+                user.userId(),
+                requestParser.parseSessionId(sessionId),
+                command.inputType(),
+                command.text(),
+                command.draftVersion()
+        ));
+    }
+
+    @PostMapping("/sessions/{sessionId}/transcriptions")
+    public Map<String, Object> transcribe(
+            @PathVariable String sessionId,
+            @RequestParam("audio") MultipartFile audio) {
+        CurrentUser user = requireCustomer();
+        if (audio == null || audio.isEmpty()) {
+            throw BookingAgentException.invalidAudio();
+        }
+        if (audio.getSize() > BookingAgentAudioValidator.MAX_AUDIO_BYTES) {
+            throw BookingAgentException.audioTooLarge();
+        }
+        try {
+            return success(bookingAgentService.transcribe(
+                    user.userId(),
+                    requestParser.parseSessionId(sessionId),
+                    audio.getBytes(),
+                    audio.getContentType()
+            ));
+        } catch (IOException exception) {
+            throw BookingAgentException.invalidAudio();
+        }
+    }
+
+    @PostMapping("/sessions/{sessionId}/fallback")
+    public Map<String, Object> handoff(
+            @PathVariable String sessionId,
+            @RequestBody JsonNode body) {
+        CurrentUser user = requireCustomer();
+        return success(bookingAgentService.handoff(
+                user.userId(),
+                requestParser.parseSessionId(sessionId),
+                requestParser.parseDraftVersion(body)
+        ));
+    }
+
+    @DeleteMapping("/sessions/{sessionId}")
+    public Map<String, Object> cancel(@PathVariable String sessionId) {
+        CurrentUser user = requireCustomer();
+        return success(bookingAgentService.cancel(
+                user.userId(),
+                requestParser.parseSessionId(sessionId)
+        ));
+    }
+
+    @ExceptionHandler(BookingAgentException.class)
+    public Map<String, Object> handleBookingAgentException(BookingAgentException exception) {
+        Map<String, Object> response = new LinkedHashMap<>();
+        response.put("code", exception.getCode());
+        response.put("message", exception.getUserMessage());
+        response.put("bizCode", exception.getBizCode());
+        return response;
+    }
+
+    @ExceptionHandler({
+            HttpMessageNotReadableException.class,
+            MissingServletRequestParameterException.class
+    })
+    public Map<String, Object> handleInvalidRequest(Exception ignored) {
+        return handleBookingAgentException(BookingAgentException.invalidInput());
+    }
+
+    @ExceptionHandler({MultipartException.class, MissingServletRequestPartException.class})
+    public Map<String, Object> handleInvalidMultipart(Exception ignored) {
+        return handleBookingAgentException(BookingAgentException.invalidAudio());
+    }
+
+    private CurrentUser requireCustomer() {
+        CurrentUser user = CurrentUserContext.require();
+        if (!user.isCustomer()) {
+            throw BookingAgentException.forbidden();
+        }
+        return user;
+    }
+
+    private Map<String, Object> success(Object data) {
+        Map<String, Object> response = new LinkedHashMap<>();
+        response.put("code", 200);
+        response.put("data", data);
+        return response;
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/api/BookingAgentDtos.java
+++ b/src/main/java/com/petstore/bookingagent/api/BookingAgentDtos.java
@ -0,0 +1,47 @@
+package com.petstore.bookingagent.api;
+
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.bookingagent.domain.BookingDraft;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+public final class BookingAgentDtos {
+    private BookingAgentDtos() {
+    }
+
+    public record SessionView(
+            String sessionId,
+            BookingAgentStatus status,
+            String assistantMessage,
+            BookingDraft draft,
+            List<SlotOption> slotOptions,
+            List<QuickReply> quickReplies,
+            boolean confirmable,
+            int draftVersion,
+            LocalDateTime expiresAt) {
+
+        public SessionView {
+            slotOptions = slotOptions == null ? List.of() : List.copyOf(slotOptions);
+            quickReplies = quickReplies == null ? List.of() : List.copyOf(quickReplies);
+        }
+    }
+
+    public record SlotOption(LocalDateTime startTime, LocalDateTime endTime, String label) {
+    }
+
+    public record QuickReply(String type, String value, String label) {
+    }
+
+    public record HandoffData(String source, BookingDraft draft) {
+        public HandoffData(BookingDraft draft) {
+            this("booking-agent-m0", draft);
+        }
+    }
+
+    public record TranscriptionData(String text) {
+    }
+
+    public record CancelData(String sessionId, BookingAgentStatus status) {
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/api/BookingAgentRequestParser.java
+++ b/src/main/java/com/petstore/bookingagent/api/BookingAgentRequestParser.java
@ -0,0 +1,78 @@
+package com.petstore.bookingagent.api;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.petstore.bookingagent.service.BookingAgentException;
+import org.springframework.stereotype.Component;
+
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+import java.util.UUID;
+
+@Component
+public class BookingAgentRequestParser {
+
+    public Long parseCreateSession(JsonNode body) {
+        requireExactFields(body, Set.of("storeId"));
+        JsonNode storeId = body.get("storeId");
+        if (storeId == null || !storeId.isIntegralNumber() || !storeId.canConvertToLong()
+                || storeId.longValue() < 1) {
+            throw BookingAgentException.invalidInput();
+        }
+        return storeId.longValue();
+    }
+
+    public SubmitMessageCommand parseMessage(JsonNode body) {
+        requireExactFields(body, Set.of("inputType", "text", "draftVersion"));
+        JsonNode inputTypeNode = body.get("inputType");
+        JsonNode textNode = body.get("text");
+        String inputType = inputTypeNode != null && inputTypeNode.isTextual()
+                ? inputTypeNode.textValue()
+                : null;
+        String text = textNode != null && textNode.isTextual() ? textNode.textValue() : null;
+        int draftVersion = parseDraftVersionNode(body.get("draftVersion"));
+        if (!("text".equals(inputType) || "voice".equals(inputType))
+                || text == null || text.isBlank() || text.strip().length() > 500) {
+            throw BookingAgentException.invalidInput();
+        }
+        return new SubmitMessageCommand(inputType, text, draftVersion);
+    }
+
+    public int parseDraftVersion(JsonNode body) {
+        requireExactFields(body, Set.of("draftVersion"));
+        return parseDraftVersionNode(body.get("draftVersion"));
+    }
+
+    public String parseSessionId(String raw) {
+        if (raw == null || raw.isBlank()) {
+            throw BookingAgentException.sessionNotFound();
+        }
+        try {
+            return UUID.fromString(raw.strip()).toString();
+        } catch (IllegalArgumentException exception) {
+            throw BookingAgentException.sessionNotFound();
+        }
+    }
+
+    private int parseDraftVersionNode(JsonNode node) {
+        if (node == null || !node.isIntegralNumber() || !node.canConvertToInt() || node.intValue() < 0) {
+            throw BookingAgentException.invalidInput();
+        }
+        return node.intValue();
+    }
+
+    private void requireExactFields(JsonNode body, Set<String> expected) {
+        if (body == null || !body.isObject()) {
+            throw BookingAgentException.invalidInput();
+        }
+        Set<String> actual = new HashSet<>();
+        Iterator<String> fields = body.fieldNames();
+        fields.forEachRemaining(actual::add);
+        if (!actual.equals(expected)) {
+            throw BookingAgentException.invalidInput();
+        }
+    }
+
+    public record SubmitMessageCommand(String inputType, String text, int draftVersion) {
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/config/BookingAgentRuntimeConfiguration.java
+++ b/src/main/java/com/petstore/bookingagent/config/BookingAgentRuntimeConfiguration.java
@ -0,0 +1,22 @@
+package com.petstore.bookingagent.config;
+
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+import java.time.Clock;
+import java.time.ZoneId;
+
+@Configuration
+@EnableScheduling
+public class BookingAgentRuntimeConfiguration {
+
+    public static final ZoneId BUSINESS_ZONE = ZoneId.of("Asia/Shanghai");
+
+    @Bean
+    @ConditionalOnMissingBean(Clock.class)
+    Clock bookingAgentClock() {
+        return Clock.system(BUSINESS_ZONE);
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/domain/BookingAgentDraftState.java
+++ b/src/main/java/com/petstore/bookingagent/domain/BookingAgentDraftState.java
@ -0,0 +1,85 @@
+package com.petstore.bookingagent.domain;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * 会话内最小结构化草稿。只保存已清洗约束与后端解析事实，不保存当轮原文、提示词或模型响应。
+ */
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+public class BookingAgentDraftState {
+    private Long storeId;
+    private String storeName;
+    /** 仅当前请求内使用；解析为权威 Pet 后不进入 draft_json。 */
+    @JsonIgnore
+    private String petQuery;
+    /** 仅当前请求内使用；解析为权威 ServiceType 后不进入 draft_json。 */
+    @JsonIgnore
+    private String serviceQuery;
+    /** 仅当前请求内使用；解析为绝对日期后不进入 draft_json。 */
+    @JsonIgnore
+    private String dateExpression;
+    private String requestedTimeStart;
+    private String requestedTimeEnd;
+    private Long petId;
+    private String petName;
+    private String petType;
+    private Long serviceTypeId;
+    private String serviceType;
+    private Integer durationMinutes;
+    private LocalDate dateConstraint;
+    private LocalDateTime appointmentTime;
+    private LocalDateTime appointmentEndTime;
+    private String remark;
+
+    public static BookingAgentDraftState initial(Long storeId, String storeName) {
+        BookingAgentDraftState state = new BookingAgentDraftState();
+        state.setStoreId(storeId);
+        state.setStoreName(storeName);
+        return state;
+    }
+
+    public BookingDraft toPublicDraft() {
+        List<BookingDraft.MissingField> missing = new ArrayList<>();
+        if (petId == null) {
+            missing.add(BookingDraft.MissingField.PET);
+        }
+        if (serviceTypeId == null) {
+            missing.add(BookingDraft.MissingField.SERVICE);
+        }
+        if (dateConstraint == null) {
+            missing.add(BookingDraft.MissingField.DATE);
+        }
+        if (appointmentTime == null) {
+            missing.add(BookingDraft.MissingField.TIME);
+        }
+        BookingDraft.TimeWindow timeWindow = requestedTimeStart == null && requestedTimeEnd == null
+                ? null
+                : new BookingDraft.TimeWindow(requestedTimeStart, requestedTimeEnd);
+        return new BookingDraft(
+                storeId,
+                storeName,
+                petId,
+                petName,
+                petType,
+                serviceTypeId,
+                serviceType,
+                durationMinutes,
+                dateConstraint,
+                timeWindow,
+                appointmentTime,
+                appointmentEndTime,
+                remark,
+                missing
+        );
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/domain/BookingAgentSession.java
+++ b/src/main/java/com/petstore/bookingagent/domain/BookingAgentSession.java
@ -0,0 +1,77 @@
+package com.petstore.bookingagent.domain;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Index;
+import jakarta.persistence.Table;
+import jakarta.persistence.UniqueConstraint;
+import lombok.Data;
+
+import java.time.LocalDateTime;
+
+@Data
+@Entity
+@Table(
+        name = "t_booking_agent_session",
+        uniqueConstraints = @UniqueConstraint(
+                name = "uk_booking_agent_session_public_id",
+                columnNames = "session_id"
+        ),
+        indexes = {
+                @Index(
+                        name = "idx_booking_agent_customer_status_expire",
+                        columnList = "customer_user_id,status,expires_at"
+                ),
+                @Index(name = "idx_booking_agent_status_expire", columnList = "status,expires_at")
+        }
+)
+public class BookingAgentSession {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Column(name = "session_id", nullable = false, length = 36)
+    private String sessionId;
+
+    @Column(name = "customer_user_id", nullable = false)
+    private Long customerUserId;
+
+    @Column(name = "store_id", nullable = false)
+    private Long storeId;
+
+    @Column(nullable = false, length = 24)
+    private String status;
+
+    @Column(name = "draft_json", nullable = false, columnDefinition = "TEXT")
+    private String draftJson;
+
+    @Column(name = "draft_version", nullable = false)
+    private Integer draftVersion;
+
+    @Column(name = "entry_source", nullable = false, length = 32)
+    private String entrySource;
+
+    @Column(name = "input_modality", length = 16)
+    private String inputModality;
+
+    @Column(name = "expires_at", nullable = false)
+    private LocalDateTime expiresAt;
+
+    @Column(name = "create_time", nullable = false)
+    private LocalDateTime createTime;
+
+    @Column(name = "update_time", nullable = false)
+    private LocalDateTime updateTime;
+
+    public BookingAgentStatus resolvedStatus() {
+        return BookingAgentStatus.fromWireValue(status);
+    }
+
+    public void setStatus(BookingAgentStatus status) {
+        this.status = status.wireValue();
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/domain/BookingAgentStatus.java
+++ b/src/main/java/com/petstore/bookingagent/domain/BookingAgentStatus.java
@ -0,0 +1,36 @@
+package com.petstore.bookingagent.domain;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import java.util.Arrays;
+
+public enum BookingAgentStatus {
+    COLLECTING("collecting"),
+    PROPOSING("proposing"),
+    CONFIRMABLE("confirmable"),
+    FALLBACK("fallback"),
+    EXPIRED("expired"),
+    CANCELLED("cancelled");
+
+    private final String wireValue;
+
+    BookingAgentStatus(String wireValue) {
+        this.wireValue = wireValue;
+    }
+
+    @JsonValue
+    public String wireValue() {
+        return wireValue;
+    }
+
+    public boolean isTerminal() {
+        return this == FALLBACK || this == EXPIRED || this == CANCELLED;
+    }
+
+    public static BookingAgentStatus fromWireValue(String value) {
+        return Arrays.stream(values())
+                .filter(status -> status.wireValue.equals(value))
+                .findFirst()
+                .orElseThrow(() -> new IllegalArgumentException("非法智能预约会话状态"));
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/domain/BookingDraft.java
+++ b/src/main/java/com/petstore/bookingagent/domain/BookingDraft.java
@ -0,0 +1,49 @@
+package com.petstore.bookingagent.domain;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.util.List;
+
+public record BookingDraft(
+        Long storeId,
+        String storeName,
+        Long petId,
+        String petName,
+        String petType,
+        Long serviceTypeId,
+        String serviceType,
+        Integer durationMinutes,
+        LocalDate dateConstraint,
+        TimeWindow timeWindow,
+        LocalDateTime appointmentTime,
+        LocalDateTime appointmentEndTime,
+        String remark,
+        List<MissingField> missingFields) {
+
+    public BookingDraft {
+        missingFields = missingFields == null ? List.of() : List.copyOf(missingFields);
+    }
+
+    public record TimeWindow(String start, String end) {
+    }
+
+    public enum MissingField {
+        PET("pet"),
+        SERVICE("service"),
+        DATE("date"),
+        TIME("time");
+
+        private final String wireValue;
+
+        MissingField(String wireValue) {
+            this.wireValue = wireValue;
+        }
+
+        @JsonValue
+        public String wireValue() {
+            return wireValue;
+        }
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/mapper/BookingAgentSessionMapper.java
+++ b/src/main/java/com/petstore/bookingagent/mapper/BookingAgentSessionMapper.java
@ -0,0 +1,34 @@
+package com.petstore.bookingagent.mapper;
+
+import com.petstore.bookingagent.domain.BookingAgentSession;
+import jakarta.persistence.LockModeType;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Lock;
+import org.springframework.data.jpa.repository.Modifying;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.time.LocalDateTime;
+import java.util.Optional;
+
+public interface BookingAgentSessionMapper extends JpaRepository<BookingAgentSession, Long> {
+
+    Optional<BookingAgentSession> findBySessionIdAndCustomerUserId(String sessionId, Long customerUserId);
+
+    @Lock(LockModeType.PESSIMISTIC_WRITE)
+    @Query("SELECT s FROM BookingAgentSession s WHERE s.sessionId = :sessionId "
+            + "AND s.customerUserId = :customerUserId")
+    Optional<BookingAgentSession> findOwnedForUpdate(
+            @Param("sessionId") String sessionId,
+            @Param("customerUserId") Long customerUserId
+    );
+
+    @Modifying(clearAutomatically = true, flushAutomatically = true)
+    @Query("UPDATE BookingAgentSession s SET s.status = 'expired', s.updateTime = :now "
+            + "WHERE s.status IN ('collecting', 'proposing', 'confirmable') AND s.expiresAt <= :now")
+    int expireActiveSessions(@Param("now") LocalDateTime now);
+
+    @Modifying(clearAutomatically = true, flushAutomatically = true)
+    @Query("DELETE FROM BookingAgentSession s WHERE s.expiresAt < :cutoff")
+    int deleteExpiredBefore(@Param("cutoff") LocalDateTime cutoff);
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentAudioValidator.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentAudioValidator.java
@ -0,0 +1,330 @@
+package com.petstore.bookingagent.service;
+
+import org.springframework.stereotype.Component;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.charset.StandardCharsets;
+import java.util.Locale;
+import java.util.Set;
+
+@Component
+public class BookingAgentAudioValidator {
+    public static final int MAX_AUDIO_BYTES = 3 * 1024 * 1024;
+    private static final double MAX_DURATION_SECONDS = 60.0;
+    private static final Set<String> ALLOWED_MIME_TYPES = Set.of(
+            "audio/aac", "audio/amr", "audio/mpeg", "audio/ogg",
+            "audio/opus", "audio/wav", "audio/webm", "video/webm"
+    );
+    private static final int[] MPEG1_LAYER3_BITRATES = {
+            0, 32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 0
+    };
+    private static final int[] MPEG2_LAYER3_BITRATES = {
+            0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 0
+    };
+    private static final int[] SAMPLE_RATES = {44100, 48000, 32000, 0};
+    private static final int[] AAC_SAMPLE_RATES = {
+            96000, 88200, 64000, 48000, 44100, 32000, 24000,
+            22050, 16000, 12000, 11025, 8000, 7350
+    };
+    private static final int[] AMR_NB_FRAME_BYTES = {13, 14, 16, 18, 20, 21, 27, 32, 6};
+    private static final int[] AMR_WB_FRAME_BYTES = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6};
+
+    public ValidatedAudio validate(byte[] bytes, String declaredMimeType) {
+        if (bytes == null || bytes.length == 0) {
+            throw BookingAgentException.invalidAudio();
+        }
+        if (bytes.length > MAX_AUDIO_BYTES) {
+            throw BookingAgentException.audioTooLarge();
+        }
+        String mimeType = normalizeMimeType(declaredMimeType);
+        if (!ALLOWED_MIME_TYPES.contains(mimeType) || !matchesHeader(bytes, mimeType)) {
+            throw BookingAgentException.invalidAudio();
+        }
+        double seconds = durationSeconds(bytes, mimeType);
+        if (!Double.isFinite(seconds) || seconds <= 0 || seconds > MAX_DURATION_SECONDS) {
+            throw BookingAgentException.invalidAudio();
+        }
+        return new ValidatedAudio(bytes.clone(), mimeType, seconds);
+    }
+
+    private String normalizeMimeType(String value) {
+        if (value == null) {
+            return "";
+        }
+        String normalized = value.strip().toLowerCase(Locale.ROOT);
+        int separator = normalized.indexOf(';');
+        if (separator >= 0) {
+            normalized = normalized.substring(0, separator).strip();
+        }
+        return switch (normalized) {
+            case "audio/x-wav" -> "audio/wav";
+            case "audio/mp3" -> "audio/mpeg";
+            default -> normalized;
+        };
+    }
+
+    private boolean matchesHeader(byte[] bytes, String mimeType) {
+        return switch (mimeType) {
+            case "audio/wav" -> ascii(bytes, 0, "RIFF") && ascii(bytes, 8, "WAVE");
+            case "audio/mpeg" -> ascii(bytes, 0, "ID3") || findMpegFrame(bytes, 0) >= 0;
+            case "audio/aac" -> bytes.length >= 7 && (bytes[0] & 0xff) == 0xff && (bytes[1] & 0xf6) == 0xf0;
+            case "audio/amr" -> ascii(bytes, 0, "#!AMR\n") || ascii(bytes, 0, "#!AMR-WB\n");
+            case "audio/ogg", "audio/opus" -> ascii(bytes, 0, "OggS");
+            case "audio/webm", "video/webm" -> bytes.length >= 4
+                    && (bytes[0] & 0xff) == 0x1a
+                    && (bytes[1] & 0xff) == 0x45
+                    && (bytes[2] & 0xff) == 0xdf
+                    && (bytes[3] & 0xff) == 0xa3;
+            default -> false;
+        };
+    }
+
+    private double durationSeconds(byte[] bytes, String mimeType) {
+        return switch (mimeType) {
+            case "audio/wav" -> wavDuration(bytes);
+            case "audio/mpeg" -> mp3Duration(bytes);
+            case "audio/aac" -> aacDuration(bytes);
+            case "audio/amr" -> amrDuration(bytes);
+            case "audio/ogg", "audio/opus" -> oggDuration(bytes);
+            case "audio/webm", "video/webm" -> webmDuration(bytes);
+            default -> Double.NaN;
+        };
+    }
+
+    private double wavDuration(byte[] bytes) {
+        int offset = 12;
+        long byteRate = -1;
+        long dataSize = -1;
+        while (offset + 8 <= bytes.length) {
+            String chunk = new String(bytes, offset, 4, StandardCharsets.US_ASCII);
+            long size = uint32le(bytes, offset + 4);
+            int body = offset + 8;
+            if (size < 0 || body + size > bytes.length) {
+                return Double.NaN;
+            }
+            if ("fmt ".equals(chunk) && size >= 16) {
+                byteRate = uint32le(bytes, body + 8);
+            } else if ("data".equals(chunk)) {
+                dataSize = size;
+            }
+            if (byteRate > 0 && dataSize >= 0) {
+                return dataSize / (double) byteRate;
+            }
+            offset = body + (int) size + ((size & 1) == 1 ? 1 : 0);
+        }
+        return Double.NaN;
+    }
+
+    private double mp3Duration(byte[] bytes) {
+        int offset = ascii(bytes, 0, "ID3") && bytes.length >= 10
+                ? 10 + synchsafeInt(bytes, 6)
+                : 0;
+        double duration = 0;
+        int frames = 0;
+        while (offset + 4 <= bytes.length) {
+            int frame = findMpegFrame(bytes, offset);
+            if (frame < 0 || frame + 4 > bytes.length) {
+                break;
+            }
+            int b1 = bytes[frame + 1] & 0xff;
+            int b2 = bytes[frame + 2] & 0xff;
+            int versionBits = (b1 >> 3) & 0x03;
+            int layerBits = (b1 >> 1) & 0x03;
+            if (versionBits == 1 || layerBits != 1) {
+                offset = frame + 1;
+                continue;
+            }
+            boolean mpeg1 = versionBits == 3;
+            int bitrateIndex = (b2 >> 4) & 0x0f;
+            int sampleIndex = (b2 >> 2) & 0x03;
+            int bitrate = (mpeg1 ? MPEG1_LAYER3_BITRATES : MPEG2_LAYER3_BITRATES)[bitrateIndex] * 1000;
+            int sampleRate = SAMPLE_RATES[sampleIndex];
+            if (versionBits == 2) sampleRate /= 2;
+            if (versionBits == 0) sampleRate /= 4;
+            if (bitrate <= 0 || sampleRate <= 0) {
+                return Double.NaN;
+            }
+            int padding = (b2 >> 1) & 1;
+            int frameLength = (mpeg1 ? 144 : 72) * bitrate / sampleRate + padding;
+            if (frameLength <= 4 || frame + frameLength > bytes.length) {
+                break;
+            }
+            duration += (mpeg1 ? 1152.0 : 576.0) / sampleRate;
+            frames++;
+            offset = frame + frameLength;
+        }
+        return frames == 0 ? Double.NaN : duration;
+    }
+
+    private double aacDuration(byte[] bytes) {
+        int offset = 0;
+        double duration = 0;
+        int frames = 0;
+        while (offset + 7 <= bytes.length) {
+            if ((bytes[offset] & 0xff) != 0xff || (bytes[offset + 1] & 0xf6) != 0xf0) {
+                return Double.NaN;
+            }
+            int sampleIndex = (bytes[offset + 2] >> 2) & 0x0f;
+            if (sampleIndex >= AAC_SAMPLE_RATES.length) {
+                return Double.NaN;
+            }
+            int frameLength = ((bytes[offset + 3] & 0x03) << 11)
+                    | ((bytes[offset + 4] & 0xff) << 3)
+                    | ((bytes[offset + 5] & 0xe0) >> 5);
+            if (frameLength < 7 || offset + frameLength > bytes.length) {
+                return Double.NaN;
+            }
+            duration += 1024.0 / AAC_SAMPLE_RATES[sampleIndex];
+            frames++;
+            offset += frameLength;
+        }
+        return frames == 0 || offset != bytes.length ? Double.NaN : duration;
+    }
+
+    private double amrDuration(byte[] bytes) {
+        boolean wideBand = ascii(bytes, 0, "#!AMR-WB\n");
+        int offset = wideBand ? 9 : 6;
+        int frames = 0;
+        int[] frameSizes = wideBand ? AMR_WB_FRAME_BYTES : AMR_NB_FRAME_BYTES;
+        while (offset < bytes.length) {
+            int frameType = (bytes[offset] >> 3) & 0x0f;
+            if (frameType >= frameSizes.length) {
+                return Double.NaN;
+            }
+            int frameLength = frameSizes[frameType];
+            if (offset + frameLength > bytes.length) {
+                return Double.NaN;
+            }
+            frames++;
+            offset += frameLength;
+        }
+        return frames == 0 ? Double.NaN : frames * 0.02;
+    }
+
+    private double oggDuration(byte[] bytes) {
+        long lastGranule = -1;
+        int sampleRate = indexOf(bytes, "OpusHead".getBytes(StandardCharsets.US_ASCII), 0) >= 0 ? 48000 : -1;
+        int vorbis = indexOf(bytes, "vorbis".getBytes(StandardCharsets.US_ASCII), 0);
+        if (sampleRate < 0 && vorbis >= 1 && vorbis + 15 <= bytes.length) {
+            sampleRate = (int) uint32le(bytes, vorbis + 11);
+        }
+        int offset = 0;
+        while (offset + 27 <= bytes.length) {
+            int page = indexOf(bytes, "OggS".getBytes(StandardCharsets.US_ASCII), offset);
+            if (page < 0 || page + 27 > bytes.length) {
+                break;
+            }
+            lastGranule = uint64le(bytes, page + 6);
+            int segments = bytes[page + 26] & 0xff;
+            if (page + 27 + segments > bytes.length) {
+                return Double.NaN;
+            }
+            int payload = 0;
+            for (int i = 0; i < segments; i++) payload += bytes[page + 27 + i] & 0xff;
+            offset = page + 27 + segments + payload;
+        }
+        return sampleRate > 0 && lastGranule > 0 ? lastGranule / (double) sampleRate : Double.NaN;
+    }
+
+    private double webmDuration(byte[] bytes) {
+        long timecodeScale = 1_000_000L;
+        Element scale = findElement(bytes, new byte[]{0x2a, (byte) 0xd7, (byte) 0xb1});
+        if (scale != null && scale.size > 0 && scale.size <= 8) {
+            timecodeScale = unsignedBigEndian(bytes, scale.dataOffset, scale.size);
+        }
+        Element duration = findElement(bytes, new byte[]{0x44, (byte) 0x89});
+        if (duration == null || (duration.size != 4 && duration.size != 8)) {
+            return Double.NaN;
+        }
+        ByteBuffer buffer = ByteBuffer.wrap(bytes, duration.dataOffset, duration.size).order(ByteOrder.BIG_ENDIAN);
+        double value = duration.size == 4 ? buffer.getFloat() : buffer.getDouble();
+        return value * timecodeScale / 1_000_000_000.0;
+    }
+
+    private Element findElement(byte[] bytes, byte[] id) {
+        int index = indexOf(bytes, id, 0);
+        if (index < 0) return null;
+        int sizeOffset = index + id.length;
+        if (sizeOffset >= bytes.length) return null;
+        int first = bytes[sizeOffset] & 0xff;
+        int length = 1;
+        int mask = 0x80;
+        while (length <= 8 && (first & mask) == 0) {
+            length++;
+            mask >>= 1;
+        }
+        if (length > 8 || sizeOffset + length > bytes.length) return null;
+        long value = first & (mask - 1);
+        for (int i = 1; i < length; i++) value = (value << 8) | (bytes[sizeOffset + i] & 0xff);
+        if (value < 0 || value > Integer.MAX_VALUE) return null;
+        int dataOffset = sizeOffset + length;
+        if (dataOffset + value > bytes.length) return null;
+        return new Element(dataOffset, (int) value);
+    }
+
+    private int findMpegFrame(byte[] bytes, int from) {
+        for (int i = Math.max(from, 0); i + 1 < bytes.length; i++) {
+            if ((bytes[i] & 0xff) == 0xff && (bytes[i + 1] & 0xe0) == 0xe0) {
+                return i;
+            }
+        }
+        return -1;
+    }
+
+    private int indexOf(byte[] bytes, byte[] needle, int from) {
+        outer:
+        for (int i = Math.max(from, 0); i + needle.length <= bytes.length; i++) {
+            for (int j = 0; j < needle.length; j++) {
+                if (bytes[i + j] != needle[j]) continue outer;
+            }
+            return i;
+        }
+        return -1;
+    }
+
+    private boolean ascii(byte[] bytes, int offset, String expected) {
+        byte[] value = expected.getBytes(StandardCharsets.US_ASCII);
+        if (offset < 0 || offset + value.length > bytes.length) return false;
+        for (int i = 0; i < value.length; i++) if (bytes[offset + i] != value[i]) return false;
+        return true;
+    }
+
+    private long uint32le(byte[] bytes, int offset) {
+        if (offset < 0 || offset + 4 > bytes.length) return -1;
+        return Integer.toUnsignedLong(ByteBuffer.wrap(bytes, offset, 4).order(ByteOrder.LITTLE_ENDIAN).getInt());
+    }
+
+    private long uint64le(byte[] bytes, int offset) {
+        if (offset < 0 || offset + 8 > bytes.length) return -1;
+        return ByteBuffer.wrap(bytes, offset, 8).order(ByteOrder.LITTLE_ENDIAN).getLong();
+    }
+
+    private long unsignedBigEndian(byte[] bytes, int offset, int size) {
+        long value = 0;
+        for (int i = 0; i < size; i++) value = (value << 8) | (bytes[offset + i] & 0xff);
+        return value;
+    }
+
+    private int synchsafeInt(byte[] bytes, int offset) {
+        if (offset < 0 || offset + 4 > bytes.length) return 0;
+        return ((bytes[offset] & 0x7f) << 21)
+                | ((bytes[offset + 1] & 0x7f) << 14)
+                | ((bytes[offset + 2] & 0x7f) << 7)
+                | (bytes[offset + 3] & 0x7f);
+    }
+
+    public record ValidatedAudio(byte[] bytes, String mimeType, double durationSeconds) {
+        public ValidatedAudio {
+            bytes = bytes.clone();
+        }
+
+        @Override
+        public byte[] bytes() {
+            return bytes.clone();
+        }
+    }
+
+    private record Element(int dataOffset, int size) {
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentContextResolver.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentContextResolver.java
@ -0,0 +1,432 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.bookingagent.provider.SensitiveTextGuard;
+import com.petstore.entity.Appointment;
+import com.petstore.entity.Pet;
+import com.petstore.entity.ScheduleBlock;
+import com.petstore.entity.ServiceType;
+import com.petstore.entity.Store;
+import com.petstore.mapper.AppointmentMapper;
+import com.petstore.mapper.PetMapper;
+import com.petstore.mapper.ScheduleBlockMapper;
+import com.petstore.mapper.StoreMapper;
+import com.petstore.service.AppointmentSlotSupport;
+import com.petstore.service.BookingCapacityService;
+import com.petstore.service.BookingDurationSupport;
+import com.petstore.service.ServiceTypeService;
+import com.petstore.service.StoreBookingWindow;
+import com.petstore.service.StoreService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+import java.time.Clock;
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.format.DateTimeFormatter;
+import java.time.format.DateTimeParseException;
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
+
+@Service
+@RequiredArgsConstructor
+public class BookingAgentContextResolver {
+    private static final DateTimeFormatter SLOT_LABEL = DateTimeFormatter.ofPattern("M月d日 HH:mm");
+
+    private final PetMapper petMapper;
+    private final ServiceTypeService serviceTypeService;
+    private final StoreMapper storeMapper;
+    private final AppointmentMapper appointmentMapper;
+    private final ScheduleBlockMapper scheduleBlockMapper;
+    private final BookingCapacityService bookingCapacityService;
+    private final BookingTimeConstraintResolver timeConstraintResolver;
+    private final Clock clock;
+
+    public BookingAgentResolution resolve(BookingAgentDraftState state, Long customerUserId) {
+        Store store = storeMapper.findByIdAndDeletedFalse(state.getStoreId()).orElse(null);
+        if (store == null) {
+            throw BookingAgentException.storeNotFound();
+        }
+        state.setStoreName(clipped(store.getName(), 128));
+
+        List<Pet> pets = petMapper.findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(customerUserId);
+        resolvePet(state, pets);
+
+        List<ServiceType> services = serviceTypeService.getByStoreId(state.getStoreId());
+        resolveService(state, services);
+
+        LocalDate today = LocalDate.now(clock);
+        if (state.getDateExpression() != null) {
+            state.setDateConstraint(timeConstraintResolver.resolve(state.getDateExpression(), today));
+        } else if (state.getDateConstraint() != null && state.getDateConstraint().isBefore(today)) {
+            state.setDateConstraint(null);
+        }
+        state.setAppointmentTime(null);
+        state.setAppointmentEndTime(null);
+
+        List<BookingAgentResolution.QuickChoice> quickReplies = firstMissingChoices(
+                state, pets, services, today
+        );
+        if (state.getPetId() == null || state.getServiceTypeId() == null || state.getDateConstraint() == null) {
+            return new BookingAgentResolution(
+                    state,
+                    BookingAgentStatus.COLLECTING,
+                    List.of(),
+                    quickReplies,
+                    false
+            );
+        }
+
+        List<BookingAgentResolution.SlotCandidate> allSlots = availableSlots(state, store);
+        List<BookingAgentResolution.SlotCandidate> preferred = filterByRequestedWindow(state, allSlots);
+        boolean exact = isExactTime(state);
+        if (exact && !preferred.isEmpty()) {
+            BookingAgentResolution.SlotCandidate selected = preferred.get(0);
+            state.setAppointmentTime(selected.startTime());
+            state.setAppointmentEndTime(selected.endTime());
+            return new BookingAgentResolution(
+                    state,
+                    BookingAgentStatus.CONFIRMABLE,
+                    List.of(),
+                    List.of(),
+                    false
+            );
+        }
+
+        boolean requestedUnavailable = (state.getRequestedTimeStart() != null
+                || state.getRequestedTimeEnd() != null) && preferred.isEmpty();
+        List<BookingAgentResolution.SlotCandidate> offered = (preferred.isEmpty() ? allSlots : preferred)
+                .stream()
+                .limit(3)
+                .toList();
+        List<BookingAgentResolution.QuickChoice> slotChoices = offered.stream()
+                .map(slot -> new BookingAgentResolution.QuickChoice(
+                        "slot",
+                        slot.startTime().toString(),
+                        slot.label()
+                ))
+                .toList();
+        return new BookingAgentResolution(
+                state,
+                BookingAgentStatus.PROPOSING,
+                offered,
+                slotChoices,
+                requestedUnavailable
+        );
+    }
+
+    public List<String> speechContextTerms(Long customerUserId, Long storeId) {
+        Set<String> candidates = new LinkedHashSet<>();
+        petMapper.findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(customerUserId).stream()
+                .map(Pet::getName)
+                .filter(this::safeContextTerm)
+                .forEach(candidates::add);
+        serviceTypeService.getByStoreId(storeId).stream()
+                .map(ServiceType::getName)
+                .filter(this::safeContextTerm)
+                .forEach(candidates::add);
+        List<String> terms = new ArrayList<>();
+        int totalLength = 0;
+        for (String candidate : candidates) {
+            int nextLength = totalLength + candidate.length() + (terms.isEmpty() ? 0 : 1);
+            if (terms.size() >= 30 || nextLength > 900) {
+                break;
+            }
+            terms.add(candidate);
+            totalLength = nextLength;
+        }
+        return List.copyOf(terms);
+    }
+
+    private void resolvePet(BookingAgentDraftState state, List<Pet> pets) {
+        if (state.getPetId() != null && pets.stream().noneMatch(p -> p.getId().equals(state.getPetId()))) {
+            clearPet(state);
+        }
+        if (state.getPetId() != null || state.getPetQuery() == null) {
+            if (state.getPetId() == null && state.getPetQuery() == null && pets.size() == 1) {
+                selectPet(state, pets.get(0));
+            }
+            return;
+        }
+        String query = normalized(state.getPetQuery());
+        List<Pet> described = new ArrayList<>();
+        List<String> choiceLabels = petChoiceLabels(pets);
+        for (int i = 0; i < pets.size(); i++) {
+            if (normalized(choiceLabels.get(i)).equals(query)) {
+                described.add(pets.get(i));
+            }
+        }
+        if (described.size() == 1) {
+            selectPet(state, described.get(0));
+            return;
+        }
+        List<Pet> exact = pets.stream()
+                .filter(p -> p.getName() != null && !p.getName().isBlank())
+                .filter(p -> normalized(p.getName()).equals(query))
+                .toList();
+        if (exact.size() == 1) {
+            selectPet(state, exact.get(0));
+            return;
+        }
+        List<Pet> fuzzy = pets.stream()
+                .filter(p -> p.getName() != null && !p.getName().isBlank())
+                .filter(p -> normalized(p.getName()).contains(query) || query.contains(normalized(p.getName())))
+                .toList();
+        if (fuzzy.size() == 1) {
+            selectPet(state, fuzzy.get(0));
+        } else {
+            clearPet(state);
+        }
+    }
+
+    private void resolveService(BookingAgentDraftState state, List<ServiceType> services) {
+        if (state.getServiceTypeId() != null
+                && services.stream().noneMatch(s -> s.getId().equals(state.getServiceTypeId()))) {
+            clearService(state);
+        }
+        if (state.getServiceTypeId() != null || state.getServiceQuery() == null) {
+            if (state.getServiceTypeId() == null && state.getServiceQuery() == null && services.size() == 1) {
+                selectService(state, services.get(0));
+            }
+            return;
+        }
+        String query = normalized(state.getServiceQuery());
+        List<ServiceType> exact = services.stream()
+                .filter(service -> service.getName() != null && !service.getName().isBlank())
+                .filter(service -> normalized(service.getName()).equals(query))
+                .toList();
+        if (exact.size() == 1) {
+            selectService(state, exact.get(0));
+            return;
+        }
+        String canonical = canonicalServiceName(query);
+        if (canonical != null) {
+            List<ServiceType> aliased = services.stream()
+                    .filter(service -> service.getName() != null && !service.getName().isBlank())
+                    .filter(service -> normalized(service.getName()).equals(normalized(canonical)))
+                    .toList();
+            if (aliased.size() == 1) {
+                selectService(state, aliased.get(0));
+                return;
+            }
+        }
+        List<ServiceType> fuzzy = services.stream()
+                .filter(service -> service.getName() != null && !service.getName().isBlank())
+                .filter(service -> {
+                    String name = normalized(service.getName());
+                    return name.contains(query) || query.contains(name);
+                })
+                .toList();
+        if (fuzzy.size() == 1) {
+            selectService(state, fuzzy.get(0));
+        } else {
+            clearService(state);
+        }
+    }
+
+    private List<BookingAgentResolution.QuickChoice> firstMissingChoices(
+            BookingAgentDraftState state,
+            List<Pet> pets,
+            List<ServiceType> services,
+            LocalDate today) {
+        if (state.getPetId() == null) {
+            List<String> labels = petChoiceLabels(pets);
+            List<BookingAgentResolution.QuickChoice> choices = new ArrayList<>();
+            for (int i = 0; i < pets.size() && choices.size() < 10; i++) {
+                String label = labels.get(i);
+                if (!label.isBlank()) {
+                    choices.add(new BookingAgentResolution.QuickChoice("pet", label, label));
+                }
+            }
+            return List.copyOf(choices);
+        }
+        if (state.getServiceTypeId() == null) {
+            return services.stream()
+                    .filter(service -> service.getName() != null && !service.getName().isBlank())
+                    .sorted(Comparator.comparing(ServiceType::getName))
+                    .limit(10)
+                    .map(service -> {
+                        String name = clipped(service.getName(), 64);
+                        return new BookingAgentResolution.QuickChoice("service", name, name);
+                    })
+                    .toList();
+        }
+        if (state.getDateConstraint() == null) {
+            return List.of(today, today.plusDays(1), today.plusDays(2)).stream()
+                    .map(date -> new BookingAgentResolution.QuickChoice(
+                            "date", date.toString(), date.getMonthValue() + "月" + date.getDayOfMonth() + "日"
+                    ))
+                    .toList();
+        }
+        return List.of();
+    }
+
+    private List<BookingAgentResolution.SlotCandidate> availableSlots(
+            BookingAgentDraftState state,
+            Store store) {
+        LocalDate date = state.getDateConstraint();
+        LocalDateTime dayStart = date.atStartOfDay();
+        LocalDateTime dayEnd = date.plusDays(1).atStartOfDay();
+        List<Appointment> appointments = appointmentMapper.findActiveByStoreAndDateRange(
+                state.getStoreId(), dayStart, dayEnd
+        );
+        List<ScheduleBlock> blocks = scheduleBlockMapper
+                .findByStoreIdAndSlotStartGreaterThanEqualAndSlotStartBeforeAndDeletedFalseOrderBySlotStartAsc(
+                        state.getStoreId(), dayStart, dayEnd
+                );
+        int duration = BookingDurationSupport.serviceMinutes(state.getDurationMinutes());
+        int capacity = StoreService.normalizeCapacity(store.getBookingCapacity());
+        StoreBookingWindow window = StoreBookingWindow.fromStore(store);
+        LocalDateTime now = LocalDateTime.now(clock);
+        List<BookingAgentResolution.SlotCandidate> available = new ArrayList<>();
+        for (LocalDateTime start : AppointmentSlotSupport.allSlotStartsOnDay(date, window)) {
+            if (!start.isAfter(now)
+                    || !AppointmentSlotSupport.isWithinBookableWindow(start, duration, window)) {
+                continue;
+            }
+            BookingCapacityService.CapacityResult result = bookingCapacityService.evaluateAppointment(
+                    start, duration, capacity, appointments, blocks
+            );
+            if (result.available()) {
+                available.add(new BookingAgentResolution.SlotCandidate(
+                        start,
+                        start.plusMinutes(duration),
+                        SLOT_LABEL.format(start)
+                ));
+            }
+        }
+        return available;
+    }
+
+    private List<BookingAgentResolution.SlotCandidate> filterByRequestedWindow(
+            BookingAgentDraftState state,
+            List<BookingAgentResolution.SlotCandidate> slots) {
+        LocalTime start = parseTime(state.getRequestedTimeStart());
+        LocalTime end = parseTime(state.getRequestedTimeEnd());
+        if (start == null && end == null) {
+            return slots;
+        }
+        return slots.stream().filter(slot -> {
+            LocalTime time = slot.startTime().toLocalTime();
+            return (start == null || !time.isBefore(start)) && (end == null || !time.isAfter(end));
+        }).toList();
+    }
+
+    private boolean isExactTime(BookingAgentDraftState state) {
+        return state.getRequestedTimeStart() != null
+                && state.getRequestedTimeStart().equals(state.getRequestedTimeEnd());
+    }
+
+    private LocalTime parseTime(String value) {
+        if (value == null) {
+            return null;
+        }
+        try {
+            return LocalTime.parse(value);
+        } catch (DateTimeParseException exception) {
+            return null;
+        }
+    }
+
+    private void selectPet(BookingAgentDraftState state, Pet pet) {
+        state.setPetId(pet.getId());
+        state.setPetName(clipped(pet.getName(), 64));
+        state.setPetType(clipped(pet.getPetType(), 32));
+    }
+
+    private void clearPet(BookingAgentDraftState state) {
+        state.setPetId(null);
+        state.setPetName(null);
+        state.setPetType(null);
+    }
+
+    private void selectService(BookingAgentDraftState state, ServiceType service) {
+        state.setServiceTypeId(service.getId());
+        state.setServiceType(clipped(service.getName(), 64));
+        state.setDurationMinutes(BookingDurationSupport.serviceMinutes(service.getDurationMinutes()));
+    }
+
+    private void clearService(BookingAgentDraftState state) {
+        state.setServiceTypeId(null);
+        state.setServiceType(null);
+        state.setDurationMinutes(null);
+    }
+
+    private String canonicalServiceName(String query) {
+        if (query.contains("全套") || query.contains("洗美")
+                || (query.contains("洗") && query.contains("美容"))) {
+            return "洗澡+美容";
+        }
+        if (query.contains("剪指甲") || "指甲".equals(query)) {
+            return "剪指甲";
+        }
+        if (query.contains("驱虫")) {
+            return "驱虫";
+        }
+        if (query.contains("美容") || query.contains("剪毛")
+                || query.contains("修毛") || query.contains("造型")) {
+            return "美容";
+        }
+        if (query.contains("洗澡") || query.contains("洗香香")
+                || query.contains("精洗") || "洗护".equals(query)) {
+            return "洗澡";
+        }
+        return null;
+    }
+
+    private List<String> petChoiceLabels(List<Pet> pets) {
+        List<String> labels = new ArrayList<>(pets.size());
+        for (int i = 0; i < pets.size(); i++) {
+            Pet pet = pets.get(i);
+            String name = clipped(pet.getName(), 32);
+            if (name == null || name.isBlank()) {
+                labels.add("");
+                continue;
+            }
+            long sameNameCount = pets.stream()
+                    .filter(other -> normalized(other.getName()).equals(normalized(pet.getName())))
+                    .count();
+            if (sameNameCount <= 1) {
+                labels.add(name);
+                continue;
+            }
+            String descriptor = pet.getPetType();
+            if (descriptor == null || descriptor.isBlank()) {
+                descriptor = pet.getBreed();
+            }
+            if (descriptor == null || descriptor.isBlank()) {
+                descriptor = "宠物";
+            }
+            labels.add(clipped(name + "（" + descriptor + " · 第" + (i + 1) + "只）", 64));
+        }
+        return labels;
+    }
+
+    private String normalized(String value) {
+        if (value == null) {
+            return "";
+        }
+        return value.strip().toLowerCase(Locale.ROOT).replaceAll("[\\s+\\-_/（）()]", "");
+    }
+
+    private boolean safeContextTerm(String term) {
+        return term != null
+                && !term.isBlank()
+                && term.length() <= 64
+                && !SensitiveTextGuard.containsForbiddenValue(term);
+    }
+
+    private String clipped(String value, int maxLength) {
+        if (value == null) {
+            return null;
+        }
+        String normalized = value.strip();
+        return normalized.length() <= maxLength ? normalized : normalized.substring(0, maxLength);
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentException.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentException.java
@ -0,0 +1,78 @@
+package com.petstore.bookingagent.service;
+
+public class BookingAgentException extends RuntimeException {
+    private final int code;
+    private final String bizCode;
+    private final String userMessage;
+
+    private BookingAgentException(int code, String bizCode, String userMessage) {
+        super(bizCode);
+        this.code = code;
+        this.bizCode = bizCode;
+        this.userMessage = userMessage;
+    }
+
+    public static BookingAgentException forbidden() {
+        return new BookingAgentException(403, "FORBIDDEN", "仅宠主可以使用智能预约");
+    }
+
+    public static BookingAgentException disabled() {
+        return new BookingAgentException(503, "AGENT_DISABLED", "智能预约暂未开启，请使用普通预约");
+    }
+
+    public static BookingAgentException storeNotFound() {
+        return new BookingAgentException(404, "STORE_NOT_FOUND", "门店不存在或已停用");
+    }
+
+    public static BookingAgentException sessionNotFound() {
+        return new BookingAgentException(404, "SESSION_NOT_FOUND", "智能预约会话不存在");
+    }
+
+    public static BookingAgentException sessionExpired() {
+        return new BookingAgentException(410, "SESSION_EXPIRED", "智能预约会话已过期，请重新开始");
+    }
+
+    public static BookingAgentException sessionTerminal() {
+        return new BookingAgentException(409, "SESSION_TERMINAL", "智能预约会话已结束");
+    }
+
+    public static BookingAgentException draftVersionConflict() {
+        return new BookingAgentException(409, "DRAFT_VERSION_CONFLICT", "草稿已更新，请刷新后重试");
+    }
+
+    public static BookingAgentException invalidInput() {
+        return new BookingAgentException(400, "INVALID_INPUT", "输入内容不符合要求");
+    }
+
+    public static BookingAgentException invalidAudio() {
+        return new BookingAgentException(400, "INVALID_AUDIO", "音频为空、格式不符或超过 60 秒");
+    }
+
+    public static BookingAgentException audioTooLarge() {
+        return new BookingAgentException(413, "AUDIO_TOO_LARGE", "单段音频不能超过 3 MB");
+    }
+
+    public static BookingAgentException rateLimited() {
+        return new BookingAgentException(429, "RATE_LIMITED", "操作过于频繁，请稍后再试");
+    }
+
+    public static BookingAgentException agentUnavailable() {
+        return new BookingAgentException(503, "AGENT_UNAVAILABLE", "暂时无法理解这段话，请使用普通预约");
+    }
+
+    public static BookingAgentException asrUnavailable() {
+        return new BookingAgentException(503, "ASR_UNAVAILABLE", "语音转写暂不可用，请改用文字输入");
+    }
+
+    public int getCode() {
+        return code;
+    }
+
+    public String getBizCode() {
+        return bizCode;
+    }
+
+    public String getUserMessage() {
+        return userMessage;
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentIntentMerger.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentIntentMerger.java
@ -0,0 +1,109 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.provider.BookingIntentPatch;
+import org.springframework.stereotype.Component;
+
+import java.util.List;
+import java.util.Objects;
+
+@Component
+public class BookingAgentIntentMerger {
+
+    public BookingIntentPatch currentIntent(BookingAgentDraftState state) {
+        BookingIntentPatch.TimeWindow timeWindow = state.getRequestedTimeStart() == null
+                && state.getRequestedTimeEnd() == null
+                ? null
+                : new BookingIntentPatch.TimeWindow(
+                        state.getRequestedTimeStart(), state.getRequestedTimeEnd()
+                );
+        return new BookingIntentPatch(
+                BookingIntentPatch.SCHEMA_VERSION,
+                BookingIntentPatch.Intent.BOOK,
+                state.getPetQuery() != null ? state.getPetQuery() : state.getPetName(),
+                state.getServiceQuery() != null ? state.getServiceQuery() : state.getServiceType(),
+                state.getDateExpression() != null
+                        ? state.getDateExpression()
+                        : (state.getDateConstraint() == null ? null : state.getDateConstraint().toString()),
+                timeWindow,
+                state.getRemark(),
+                List.of(),
+                List.of(),
+                BookingIntentPatch.NextAction.RESOLVE_CONTEXT
+        );
+    }
+
+    public BookingAgentDraftState merge(BookingAgentDraftState state, BookingIntentPatch patch) {
+        if (state == null || patch == null) {
+            throw BookingAgentException.agentUnavailable();
+        }
+        for (BookingIntentPatch.ClearField clearField : patch.clearFields()) {
+            clear(state, clearField);
+        }
+        if (patch.petQuery() != null && !Objects.equals(state.getPetQuery(), patch.petQuery())) {
+            state.setPetQuery(patch.petQuery());
+            clearResolvedPet(state);
+        }
+        if (patch.serviceQuery() != null && !Objects.equals(state.getServiceQuery(), patch.serviceQuery())) {
+            state.setServiceQuery(patch.serviceQuery());
+            clearResolvedService(state);
+        }
+        if (patch.dateExpression() != null && !Objects.equals(state.getDateExpression(), patch.dateExpression())) {
+            state.setDateExpression(patch.dateExpression());
+            state.setDateConstraint(null);
+            clearResolvedTime(state);
+        }
+        if (patch.timeWindow() != null) {
+            state.setRequestedTimeStart(patch.timeWindow().start());
+            state.setRequestedTimeEnd(patch.timeWindow().end());
+            clearResolvedTime(state);
+        }
+        if (patch.remark() != null) {
+            state.setRemark(patch.remark());
+        }
+        return state;
+    }
+
+    private void clear(BookingAgentDraftState state, BookingIntentPatch.ClearField field) {
+        switch (field) {
+            case PET_QUERY -> {
+                state.setPetQuery(null);
+                clearResolvedPet(state);
+            }
+            case SERVICE_QUERY -> {
+                state.setServiceQuery(null);
+                clearResolvedService(state);
+            }
+            case DATE_EXPRESSION -> {
+                state.setDateExpression(null);
+                state.setDateConstraint(null);
+                clearResolvedTime(state);
+            }
+            case TIME_WINDOW -> {
+                state.setRequestedTimeStart(null);
+                state.setRequestedTimeEnd(null);
+                clearResolvedTime(state);
+            }
+            case REMARK -> state.setRemark(null);
+        }
+    }
+
+    private void clearResolvedPet(BookingAgentDraftState state) {
+        state.setPetId(null);
+        state.setPetName(null);
+        state.setPetType(null);
+        clearResolvedTime(state);
+    }
+
+    private void clearResolvedService(BookingAgentDraftState state) {
+        state.setServiceTypeId(null);
+        state.setServiceType(null);
+        state.setDurationMinutes(null);
+        clearResolvedTime(state);
+    }
+
+    private void clearResolvedTime(BookingAgentDraftState state) {
+        state.setAppointmentTime(null);
+        state.setAppointmentEndTime(null);
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentRateLimiter.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentRateLimiter.java
@ -0,0 +1,68 @@
+package com.petstore.bookingagent.service;
+
+import org.springframework.stereotype.Component;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.Duration;
+import java.util.ArrayDeque;
+import java.util.Deque;
+import java.util.concurrent.ConcurrentHashMap;
+
+/** 单实例 M0 限流；进入多实例前必须替换为共享状态。 */
+@Component
+public class BookingAgentRateLimiter {
+    private static final Duration WINDOW = Duration.ofMinutes(10);
+    private static final int MAX_BUCKETS = 10_000;
+
+    private final Clock clock;
+    private final ConcurrentHashMap<BucketKey, Deque<Instant>> buckets = new ConcurrentHashMap<>();
+
+    public BookingAgentRateLimiter(Clock clock) {
+        this.clock = clock;
+    }
+
+    public void acquire(Long customerUserId, Operation operation) {
+        if (customerUserId == null || operation == null) {
+            throw BookingAgentException.invalidInput();
+        }
+        Instant now = clock.instant();
+        Deque<Instant> bucket = buckets.computeIfAbsent(
+                new BucketKey(customerUserId, operation),
+                ignored -> new ArrayDeque<>()
+        );
+        synchronized (bucket) {
+            Instant cutoff = now.minus(WINDOW);
+            while (!bucket.isEmpty() && !bucket.peekFirst().isAfter(cutoff)) {
+                bucket.removeFirst();
+            }
+            if (bucket.size() >= operation.limit) {
+                throw BookingAgentException.rateLimited();
+            }
+            bucket.addLast(now);
+        }
+        if (buckets.size() > MAX_BUCKETS) {
+            buckets.entrySet().removeIf(entry -> {
+                Deque<Instant> value = entry.getValue();
+                synchronized (value) {
+                    return value.isEmpty() || !value.peekLast().isAfter(now.minus(WINDOW));
+                }
+            });
+        }
+    }
+
+    public enum Operation {
+        CREATE_SESSION(5),
+        SUBMIT_MESSAGE(30),
+        TRANSCRIBE_AUDIO(10);
+
+        private final int limit;
+
+        Operation(int limit) {
+            this.limit = limit;
+        }
+    }
+
+    private record BucketKey(Long customerUserId, Operation operation) {
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentReplyRenderer.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentReplyRenderer.java
@ -0,0 +1,30 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.domain.BookingDraft;
+import org.springframework.stereotype.Component;
+
+@Component
+public class BookingAgentReplyRenderer {
+
+    public String render(BookingAgentResolution resolution) {
+        if (resolution.status().wireValue().equals("confirmable")) {
+            return "预约草稿已准备好，请确认后带入普通预约。";
+        }
+        BookingDraft draft = resolution.state().toPublicDraft();
+        if (draft.missingFields().contains(BookingDraft.MissingField.PET)) {
+            return "请选择要预约的宠物。";
+        }
+        if (draft.missingFields().contains(BookingDraft.MissingField.SERVICE)) {
+            return "请选择需要的服务项目。";
+        }
+        if (draft.missingFields().contains(BookingDraft.MissingField.DATE)) {
+            return "请选择想预约的日期。";
+        }
+        if (!resolution.slotOptions().isEmpty()) {
+            return resolution.requestedSlotUnavailable()
+                    ? "你选的时间暂不可约，可以看看这些时段。"
+                    : "找到以下可约时间，请选择一个。";
+        }
+        return "这一天暂时没有可约时段，请换个日期。";
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentResolution.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentResolution.java
@ -0,0 +1,26 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+public record BookingAgentResolution(
+        BookingAgentDraftState state,
+        BookingAgentStatus status,
+        List<SlotCandidate> slotOptions,
+        List<QuickChoice> quickReplies,
+        boolean requestedSlotUnavailable) {
+
+    public BookingAgentResolution {
+        slotOptions = slotOptions == null ? List.of() : List.copyOf(slotOptions);
+        quickReplies = quickReplies == null ? List.of() : List.copyOf(quickReplies);
+    }
+
+    public record SlotCandidate(LocalDateTime startTime, LocalDateTime endTime, String label) {
+    }
+
+    public record QuickChoice(String type, String value, String label) {
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentService.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentService.java
@ -0,0 +1,266 @@
+package com.petstore.bookingagent.service;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.petstore.bookingagent.api.BookingAgentDtos;
+import com.petstore.bookingagent.config.BookingAgentProperties;
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.domain.BookingAgentSession;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.bookingagent.mapper.BookingAgentSessionMapper;
+import com.petstore.bookingagent.provider.BookingIntentExtractor;
+import com.petstore.bookingagent.provider.BookingIntentPatch;
+import com.petstore.bookingagent.provider.BookingIntentRequest;
+import com.petstore.bookingagent.provider.ProviderException;
+import com.petstore.bookingagent.provider.SpeechTranscriber;
+import com.petstore.bookingagent.provider.SpeechTranscription;
+import com.petstore.bookingagent.provider.SpeechTranscriptionRequest;
+import com.petstore.entity.Store;
+import com.petstore.mapper.StoreMapper;
+import com.petstore.service.BusinessEventService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Clock;
+import java.time.LocalDateTime;
+import java.time.temporal.ChronoUnit;
+import java.util.List;
+import java.util.UUID;
+
+@Service
+@RequiredArgsConstructor
+public class BookingAgentService {
+    private static final String ENTRY_SOURCE = "appointment_create";
+    private static final int SESSION_TTL_MINUTES = 30;
+
+    private final BookingAgentProperties properties;
+    private final BookingAgentSessionMapper sessionMapper;
+    private final StoreMapper storeMapper;
+    private final BookingIntentExtractor intentExtractor;
+    private final SpeechTranscriber speechTranscriber;
+    private final BookingAgentContextResolver contextResolver;
+    private final BookingAgentIntentMerger intentMerger;
+    private final BookingAgentReplyRenderer replyRenderer;
+    private final BookingAgentAudioValidator audioValidator;
+    private final BookingAgentRateLimiter rateLimiter;
+    private final BusinessEventService businessEventService;
+    private final ObjectMapper objectMapper;
+    private final Clock clock;
+
+    @Transactional(noRollbackFor = BookingAgentException.class)
+    public BookingAgentDtos.SessionView createSession(Long customerUserId, Long storeId) {
+        requireEnabled();
+        rateLimiter.acquire(customerUserId, BookingAgentRateLimiter.Operation.CREATE_SESSION);
+        Store store = storeId == null
+                ? null
+                : storeMapper.findByIdAndDeletedFalse(storeId).orElse(null);
+        if (store == null) {
+            throw BookingAgentException.storeNotFound();
+        }
+        LocalDateTime now = now();
+        BookingAgentDraftState state = BookingAgentDraftState.initial(store.getId(), store.getName());
+        BookingAgentResolution resolution = contextResolver.resolve(state, customerUserId);
+
+        BookingAgentSession session = new BookingAgentSession();
+        session.setSessionId(UUID.randomUUID().toString());
+        session.setCustomerUserId(customerUserId);
+        session.setStoreId(store.getId());
+        session.setStatus(resolution.status());
+        session.setDraftJson(writeDraft(resolution.state()));
+        session.setDraftVersion(0);
+        session.setEntrySource(ENTRY_SOURCE);
+        session.setInputModality(null);
+        session.setExpiresAt(now.plusMinutes(SESSION_TTL_MINUTES));
+        session.setCreateTime(now);
+        session.setUpdateTime(now);
+        BookingAgentSession saved = sessionMapper.save(session);
+        businessEventService.recordBookingAgentStarted(saved);
+        return toView(saved, resolution);
+    }
+
+    @Transactional(noRollbackFor = BookingAgentException.class)
+    public BookingAgentDtos.SessionView submitMessage(
+            Long customerUserId,
+            String sessionId,
+            String inputType,
+            String text,
+            int draftVersion) {
+        requireEnabled();
+        rateLimiter.acquire(customerUserId, BookingAgentRateLimiter.Operation.SUBMIT_MESSAGE);
+        BookingAgentSession session = loadActiveForUpdate(sessionId, customerUserId);
+        if (!session.getDraftVersion().equals(draftVersion)) {
+            throw BookingAgentException.draftVersionConflict();
+        }
+        BookingAgentDraftState state = readDraft(session.getDraftJson());
+        BookingIntentPatch patch;
+        try {
+            patch = intentExtractor.extract(new BookingIntentRequest(
+                    text,
+                    intentMerger.currentIntent(state)
+            ));
+        } catch (ProviderException exception) {
+            if (exception.getReason() == ProviderException.Reason.INVALID_INPUT) {
+                throw BookingAgentException.invalidInput();
+            }
+            markProviderFallback(session);
+            throw BookingAgentException.agentUnavailable();
+        }
+
+        BookingAgentDraftState merged = intentMerger.merge(state, patch);
+        BookingAgentResolution resolution = contextResolver.resolve(merged, customerUserId);
+        BookingAgentStatus previous = session.resolvedStatus();
+        LocalDateTime now = now();
+        session.setStatus(resolution.status());
+        session.setDraftJson(writeDraft(resolution.state()));
+        session.setDraftVersion(session.getDraftVersion() + 1);
+        session.setInputModality(mergeInputModality(session.getInputModality(), inputType));
+        session.setUpdateTime(now);
+        BookingAgentSession saved = sessionMapper.save(session);
+        if (previous != BookingAgentStatus.CONFIRMABLE
+                && resolution.status() == BookingAgentStatus.CONFIRMABLE) {
+            businessEventService.recordBookingAgentDraftReady(saved);
+        }
+        return toView(saved, resolution);
+    }
+
+    @Transactional(noRollbackFor = BookingAgentException.class)
+    public BookingAgentDtos.TranscriptionData transcribe(
+            Long customerUserId,
+            String sessionId,
+            byte[] audio,
+            String mimeType) {
+        requireEnabled();
+        rateLimiter.acquire(customerUserId, BookingAgentRateLimiter.Operation.TRANSCRIBE_AUDIO);
+        BookingAgentSession session = loadActiveForUpdate(sessionId, customerUserId);
+        BookingAgentAudioValidator.ValidatedAudio validated = audioValidator.validate(audio, mimeType);
+        List<String> terms = contextResolver.speechContextTerms(customerUserId, session.getStoreId());
+        try {
+            SpeechTranscription transcription = speechTranscriber.transcribe(new SpeechTranscriptionRequest(
+                    validated.bytes(), validated.mimeType(), terms
+            ));
+            return new BookingAgentDtos.TranscriptionData(transcription.text());
+        } catch (ProviderException exception) {
+            if (exception.getReason() == ProviderException.Reason.INVALID_INPUT) {
+                throw BookingAgentException.invalidAudio();
+            }
+            throw BookingAgentException.asrUnavailable();
+        }
+    }
+
+    @Transactional(noRollbackFor = BookingAgentException.class)
+    public BookingAgentDtos.HandoffData handoff(
+            Long customerUserId,
+            String sessionId,
+            int draftVersion) {
+        requireEnabled();
+        BookingAgentSession session = loadActiveForUpdate(sessionId, customerUserId);
+        if (!session.getDraftVersion().equals(draftVersion)) {
+            throw BookingAgentException.draftVersionConflict();
+        }
+        BookingAgentDraftState state = readDraft(session.getDraftJson());
+        session.setStatus(BookingAgentStatus.FALLBACK);
+        session.setUpdateTime(now());
+        BookingAgentSession saved = sessionMapper.save(session);
+        businessEventService.recordBookingAgentFallback(saved, "user");
+        return new BookingAgentDtos.HandoffData(state.toPublicDraft());
+    }
+
+    @Transactional(noRollbackFor = BookingAgentException.class)
+    public BookingAgentDtos.CancelData cancel(Long customerUserId, String sessionId) {
+        BookingAgentSession session = loadActiveForUpdate(sessionId, customerUserId);
+        session.setStatus(BookingAgentStatus.CANCELLED);
+        session.setUpdateTime(now());
+        BookingAgentSession saved = sessionMapper.save(session);
+        return new BookingAgentDtos.CancelData(saved.getSessionId(), BookingAgentStatus.CANCELLED);
+    }
+
+    private BookingAgentSession loadActiveForUpdate(String sessionId, Long customerUserId) {
+        BookingAgentSession session = sessionMapper.findOwnedForUpdate(sessionId, customerUserId)
+                .orElseThrow(BookingAgentException::sessionNotFound);
+        BookingAgentStatus status = session.resolvedStatus();
+        if (status == BookingAgentStatus.EXPIRED) {
+            throw BookingAgentException.sessionExpired();
+        }
+        if (status.isTerminal()) {
+            throw BookingAgentException.sessionTerminal();
+        }
+        LocalDateTime now = now();
+        if (!session.getExpiresAt().isAfter(now)) {
+            session.setStatus(BookingAgentStatus.EXPIRED);
+            session.setUpdateTime(now);
+            sessionMapper.save(session);
+            throw BookingAgentException.sessionExpired();
+        }
+        return session;
+    }
+
+    private void markProviderFallback(BookingAgentSession session) {
+        session.setStatus(BookingAgentStatus.FALLBACK);
+        session.setUpdateTime(now());
+        BookingAgentSession saved = sessionMapper.save(session);
+        businessEventService.recordBookingAgentFallback(saved, "llm_unavailable");
+    }
+
+    private BookingAgentDtos.SessionView toView(
+            BookingAgentSession session,
+            BookingAgentResolution resolution) {
+        List<BookingAgentDtos.SlotOption> slots = resolution.slotOptions().stream()
+                .map(slot -> new BookingAgentDtos.SlotOption(
+                        slot.startTime(), slot.endTime(), slot.label()
+                ))
+                .toList();
+        List<BookingAgentDtos.QuickReply> quickReplies = resolution.quickReplies().stream()
+                .map(choice -> new BookingAgentDtos.QuickReply(
+                        choice.type(), choice.value(), choice.label()
+                ))
+                .toList();
+        return new BookingAgentDtos.SessionView(
+                session.getSessionId(),
+                session.resolvedStatus(),
+                replyRenderer.render(resolution),
+                resolution.state().toPublicDraft(),
+                slots,
+                quickReplies,
+                resolution.status() == BookingAgentStatus.CONFIRMABLE,
+                session.getDraftVersion(),
+                session.getExpiresAt()
+        );
+    }
+
+    private BookingAgentDraftState readDraft(String json) {
+        try {
+            return objectMapper.readValue(json, BookingAgentDraftState.class);
+        } catch (JsonProcessingException exception) {
+            throw BookingAgentException.agentUnavailable();
+        }
+    }
+
+    private String writeDraft(BookingAgentDraftState state) {
+        try {
+            return objectMapper.writeValueAsString(state);
+        } catch (JsonProcessingException exception) {
+            throw BookingAgentException.agentUnavailable();
+        }
+    }
+
+    private String mergeInputModality(String current, String incoming) {
+        if (!("text".equals(incoming) || "voice".equals(incoming))) {
+            throw BookingAgentException.invalidInput();
+        }
+        if (current == null || current.isBlank()) {
+            return incoming;
+        }
+        return current.equals(incoming) ? current : "mixed";
+    }
+
+    private void requireEnabled() {
+        if (!properties.isEnabled()) {
+            throw BookingAgentException.disabled();
+        }
+    }
+
+    private LocalDateTime now() {
+        return LocalDateTime.now(clock).truncatedTo(ChronoUnit.SECONDS);
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingAgentSessionJanitor.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingAgentSessionJanitor.java
@ -0,0 +1,37 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.mapper.BookingAgentSessionMapper;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Clock;
+import java.time.LocalDateTime;
+import java.time.temporal.ChronoUnit;
+
+@Component
+@RequiredArgsConstructor
+@Slf4j
+public class BookingAgentSessionJanitor {
+    private static final int RETENTION_HOURS_AFTER_EXPIRY = 24;
+
+    private final BookingAgentSessionMapper sessionMapper;
+    private final Clock clock;
+
+    @Scheduled(cron = "0 0 * * * *", zone = "Asia/Shanghai")
+    @Transactional
+    public void maintainSessions() {
+        LocalDateTime now = LocalDateTime.now(clock).truncatedTo(ChronoUnit.SECONDS);
+        int expiredCount = sessionMapper.expireActiveSessions(now);
+        int deletedCount = sessionMapper.deleteExpiredBefore(now.minusHours(RETENTION_HOURS_AFTER_EXPIRY));
+        if (expiredCount > 0 || deletedCount > 0) {
+            log.info(
+                    "booking-agent session maintenance expiredCount={} deletedCount={}",
+                    expiredCount,
+                    deletedCount
+            );
+        }
+    }
+}
--- a/src/main/java/com/petstore/bookingagent/service/BookingTimeConstraintResolver.java
+++ b/src/main/java/com/petstore/bookingagent/service/BookingTimeConstraintResolver.java
@ -0,0 +1,72 @@
+package com.petstore.bookingagent.service;
+
+import org.springframework.stereotype.Component;
+
+import java.time.DateTimeException;
+import java.time.DayOfWeek;
+import java.time.LocalDate;
+import java.time.MonthDay;
+import java.time.temporal.TemporalAdjusters;
+import java.util.Map;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+@Component
+public class BookingTimeConstraintResolver {
+    private static final Pattern MONTH_DAY = Pattern.compile("^(\\d{1,2})月(\\d{1,2})日$");
+    private static final Pattern WEEKDAY = Pattern.compile("^(本周|这周|下周)?([一二三四五六日天])$");
+    private static final Map<String, DayOfWeek> DAY_OF_WEEK = Map.of(
+            "一", DayOfWeek.MONDAY,
+            "二", DayOfWeek.TUESDAY,
+            "三", DayOfWeek.WEDNESDAY,
+            "四", DayOfWeek.THURSDAY,
+            "五", DayOfWeek.FRIDAY,
+            "六", DayOfWeek.SATURDAY,
+            "日", DayOfWeek.SUNDAY,
+            "天", DayOfWeek.SUNDAY
+    );
+
+    public LocalDate resolve(String expression, LocalDate today) {
+        if (expression == null || expression.isBlank() || today == null) {
+            return null;
+        }
+        String value = expression.strip().replace("星期", "周");
+        LocalDate resolved;
+        try {
+            resolved = switch (value) {
+                case "今天" -> today;
+                case "明天" -> today.plusDays(1);
+                case "后天" -> today.plusDays(2);
+                default -> resolveStructured(value, today);
+            };
+        } catch (DateTimeException exception) {
+            return null;
+        }
+        return resolved != null && !resolved.isBefore(today) ? resolved : null;
+    }
+
+    private LocalDate resolveStructured(String value, LocalDate today) {
+        try {
+            return LocalDate.parse(value);
+        } catch (DateTimeException ignored) {
+            // Continue with supported Chinese forms.
+        }
+        Matcher monthDay = MONTH_DAY.matcher(value);
+        if (monthDay.matches()) {
+            MonthDay md = MonthDay.of(
+                    Integer.parseInt(monthDay.group(1)),
+                    Integer.parseInt(monthDay.group(2))
+            );
+            return md.atYear(today.getYear());
+        }
+        String normalizedWeek = value.startsWith("周") ? "本周" + value.substring(1) : value;
+        Matcher weekday = WEEKDAY.matcher(normalizedWeek);
+        if (!weekday.matches()) {
+            return null;
+        }
+        LocalDate monday = today.with(TemporalAdjusters.previousOrSame(DayOfWeek.MONDAY));
+        int weekOffset = "下周".equals(weekday.group(1)) ? 1 : 0;
+        DayOfWeek target = DAY_OF_WEEK.get(weekday.group(2));
+        return monday.plusWeeks(weekOffset).plusDays(target.getValue() - 1L);
+    }
+}
--- a/src/main/java/com/petstore/service/BusinessEventService.java
+++ b/src/main/java/com/petstore/service/BusinessEventService.java
@ -2,6 +2,7 @@ package com.petstore.service;

 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.petstore.bookingagent.domain.BookingAgentSession;
 import com.petstore.entity.Appointment;
 import com.petstore.entity.BusinessEvent;
 import com.petstore.entity.FollowUpTask;
@ -44,6 +45,9 @@ public class BusinessEventService {
    public static final String FOLLOW_UP_CANCELED = "follow_up_canceled";
    public static final String REBOOK_CREATED = "rebook_created";
    public static final String STORE_REGISTERED = "store_registered";
+    public static final String BOOKING_AGENT_STARTED = "booking_agent_started";
+    public static final String BOOKING_AGENT_DRAFT_READY = "booking_agent_draft_ready";
+    public static final String BOOKING_AGENT_FALLBACK = "booking_agent_fallback";

    private static final Set<String> FORBIDDEN_METADATA_FRAGMENTS = Set.of(
            "phone", "token", "url", "openid", "unionid",
@ -72,6 +76,58 @@ public class BusinessEventService {
        ));
    }

+    @Transactional
+    public BusinessEvent recordBookingAgentStarted(BookingAgentSession session) {
+        return record(new EventCommand(
+                BOOKING_AGENT_STARTED,
+                session.getStoreId(),
+                resolveStoreCustomerId(session.getStoreId(), session.getCustomerUserId()),
+                "booking_agent_session",
+                session.getId(),
+                session.getCustomerUserId(),
+                "customer",
+                "customer",
+                session.getCreateTime(),
+                "booking_agent_started:" + session.getId(),
+                Map.of("entrySource", session.getEntrySource())
+        ));
+    }
+
+    @Transactional
+    public BusinessEvent recordBookingAgentDraftReady(BookingAgentSession session) {
+        return record(new EventCommand(
+                BOOKING_AGENT_DRAFT_READY,
+                session.getStoreId(),
+                resolveStoreCustomerId(session.getStoreId(), session.getCustomerUserId()),
+                "booking_agent_session",
+                session.getId(),
+                session.getCustomerUserId(),
+                "customer",
+                "customer",
+                session.getUpdateTime(),
+                "booking_agent_draft_ready:" + session.getId(),
+                Map.of("inputModality", session.getInputModality())
+        ));
+    }
+
+    @Transactional
+    public BusinessEvent recordBookingAgentFallback(BookingAgentSession session, String reason) {
+        String safeReason = "llm_unavailable".equals(reason) ? "llm_unavailable" : "user";
+        return record(new EventCommand(
+                BOOKING_AGENT_FALLBACK,
+                session.getStoreId(),
+                resolveStoreCustomerId(session.getStoreId(), session.getCustomerUserId()),
+                "booking_agent_session",
+                session.getId(),
+                session.getCustomerUserId(),
+                "customer",
+                "customer",
+                session.getUpdateTime(),
+                "booking_agent_fallback:" + session.getId(),
+                Map.of("reason", safeReason)
+        ));
+    }
+
    @Transactional
    public BusinessEvent recordAppointmentCreated(
            Appointment appointment,
--- a/src/test/java/com/petstore/bookingagent/api/BookingAgentControllerTest.java
+++ b/src/test/java/com/petstore/bookingagent/api/BookingAgentControllerTest.java
@ -0,0 +1,178 @@
+package com.petstore.bookingagent.api;
+
+import com.petstore.auth.CurrentUser;
+import com.petstore.auth.CurrentUserContext;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.bookingagent.domain.BookingDraft;
+import com.petstore.bookingagent.service.BookingAgentAudioValidator;
+import com.petstore.bookingagent.service.BookingAgentService;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.http.MediaType;
+import org.springframework.mock.web.MockMultipartFile;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.multipart;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@ExtendWith(MockitoExtension.class)
+class BookingAgentControllerTest {
+    private static final String SESSION_ID = "f5d7b3e2-9c25-41d3-87b0-6e4895b24d50";
+
+    @Mock private BookingAgentService bookingAgentService;
+    private MockMvc mockMvc;
+
+    @BeforeEach
+    void setUp() {
+        BookingAgentController controller = new BookingAgentController(
+                bookingAgentService,
+                new BookingAgentRequestParser()
+        );
+        mockMvc = MockMvcBuilders.standaloneSetup(controller).build();
+        CurrentUserContext.set(new CurrentUser(99L, null, "customer"));
+    }
+
+    @AfterEach
+    void tearDown() {
+        CurrentUserContext.clear();
+    }
+
+    @Test
+    void createSessionUsesCurrentCustomerAndFrozenBodyShape() throws Exception {
+        when(bookingAgentService.createSession(99L, 10L)).thenReturn(sessionView());
+
+        mockMvc.perform(post("/api/booking-agent/sessions")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"storeId\":10}"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(200))
+                .andExpect(jsonPath("$.data.sessionId").value(SESSION_ID))
+                .andExpect(jsonPath("$.data.status").value("collecting"))
+                .andExpect(jsonPath("$.data.draft.storeId").value(10));
+
+        verify(bookingAgentService).createSession(99L, 10L);
+    }
+
+    @Test
+    void nonCustomerGetsBodyForbiddenWithoutCallingService() throws Exception {
+        CurrentUserContext.set(new CurrentUser(7L, 10L, "staff"));
+
+        mockMvc.perform(post("/api/booking-agent/sessions")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"storeId\":10}"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.code").value(403))
+                .andExpect(jsonPath("$.bizCode").value("FORBIDDEN"));
+
+        verify(bookingAgentService, never()).createSession(any(), any());
+    }
+
+    @Test
+    void unknownFieldAndMalformedJsonReturnFrozenInvalidInputBody() throws Exception {
+        mockMvc.perform(post("/api/booking-agent/sessions")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"storeId\":10,\"userId\":99}"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.bizCode").value("INVALID_INPUT"));
+
+        mockMvc.perform(post("/api/booking-agent/sessions")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{not-json"))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.bizCode").value("INVALID_INPUT"));
+    }
+
+    @Test
+    void messageHandoffAndCancelPassOnlyCurrentOwnerAndVersion() throws Exception {
+        when(bookingAgentService.submitMessage(99L, SESSION_ID, "text", "明天下午", 0))
+                .thenReturn(sessionView());
+        when(bookingAgentService.handoff(99L, SESSION_ID, 0))
+                .thenReturn(new BookingAgentDtos.HandoffData(sessionView().draft()));
+        when(bookingAgentService.cancel(99L, SESSION_ID))
+                .thenReturn(new BookingAgentDtos.CancelData(SESSION_ID, BookingAgentStatus.CANCELLED));
+
+        mockMvc.perform(post("/api/booking-agent/sessions/{sessionId}/messages", SESSION_ID)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"inputType\":\"text\",\"text\":\"明天下午\",\"draftVersion\":0}"))
+                .andExpect(jsonPath("$.code").value(200));
+        mockMvc.perform(post("/api/booking-agent/sessions/{sessionId}/fallback", SESSION_ID)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content("{\"draftVersion\":0}"))
+                .andExpect(jsonPath("$.data.source").value("booking-agent-m0"));
+        mockMvc.perform(delete("/api/booking-agent/sessions/{sessionId}", SESSION_ID))
+                .andExpect(jsonPath("$.data.status").value("cancelled"));
+
+        verify(bookingAgentService).submitMessage(99L, SESSION_ID, "text", "明天下午", 0);
+        verify(bookingAgentService).handoff(99L, SESSION_ID, 0);
+        verify(bookingAgentService).cancel(99L, SESSION_ID);
+    }
+
+    @Test
+    void missingAndOversizedAudioFailBeforeProvider() throws Exception {
+        mockMvc.perform(multipart("/api/booking-agent/sessions/{sessionId}/transcriptions", SESSION_ID))
+                .andExpect(jsonPath("$.bizCode").value("INVALID_AUDIO"));
+
+        MockMultipartFile oversized = new MockMultipartFile(
+                "audio",
+                "voice.wav",
+                "audio/wav",
+                new byte[BookingAgentAudioValidator.MAX_AUDIO_BYTES + 1]
+        );
+        mockMvc.perform(multipart("/api/booking-agent/sessions/{sessionId}/transcriptions", SESSION_ID)
+                        .file(oversized))
+                .andExpect(jsonPath("$.code").value(413))
+                .andExpect(jsonPath("$.bizCode").value("AUDIO_TOO_LARGE"));
+
+        verify(bookingAgentService, never()).transcribe(any(), any(), any(), any());
+    }
+
+    private BookingAgentDtos.SessionView sessionView() {
+        BookingDraft draft = new BookingDraft(
+                10L,
+                "宠小它测试店",
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                null,
+                List.of(
+                        BookingDraft.MissingField.PET,
+                        BookingDraft.MissingField.SERVICE,
+                        BookingDraft.MissingField.DATE,
+                        BookingDraft.MissingField.TIME
+                )
+        );
+        return new BookingAgentDtos.SessionView(
+                SESSION_ID,
+                BookingAgentStatus.COLLECTING,
+                "请选择要预约的宠物。",
+                draft,
+                List.of(),
+                List.of(),
+                false,
+                0,
+                LocalDateTime.of(2026, 8, 2, 10, 30)
+        );
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/api/BookingAgentRequestParserTest.java
+++ b/src/test/java/com/petstore/bookingagent/api/BookingAgentRequestParserTest.java
@ -0,0 +1,54 @@
+package com.petstore.bookingagent.api;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.petstore.bookingagent.service.BookingAgentException;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class BookingAgentRequestParserTest {
+    private final ObjectMapper objectMapper = new ObjectMapper();
+    private final BookingAgentRequestParser parser = new BookingAgentRequestParser();
+
+    @Test
+    void parsesFrozenRequestShapes() throws Exception {
+        assertEquals(10L, parser.parseCreateSession(objectMapper.readTree("{\"storeId\":10}")));
+        BookingAgentRequestParser.SubmitMessageCommand message = parser.parseMessage(objectMapper.readTree(
+                "{\"inputType\":\"voice\",\"text\":\"明天下午\",\"draftVersion\":2}"
+        ));
+        assertEquals("voice", message.inputType());
+        assertEquals(2, message.draftVersion());
+        assertEquals(3, parser.parseDraftVersion(objectMapper.readTree("{\"draftVersion\":3}")));
+    }
+
+    @Test
+    void rejectsUnknownMissingAndInvalidFields() throws Exception {
+        assertInvalid("{\"storeId\":10,\"userId\":99}", parser::parseCreateSession);
+        assertInvalid("{\"storeId\":0}", parser::parseCreateSession);
+        assertInvalid("{\"inputType\":\"audio\",\"text\":\"x\",\"draftVersion\":0}", parser::parseMessage);
+        assertInvalid("{\"inputType\":\"text\",\"text\":\"\",\"draftVersion\":0}", parser::parseMessage);
+        assertInvalid("{\"draftVersion\":-1}", parser::parseDraftVersion);
+    }
+
+    @Test
+    void malformedSessionIdIsHiddenAsNotFound() {
+        BookingAgentException exception = assertThrows(
+                BookingAgentException.class,
+                () -> parser.parseSessionId("not-a-session")
+        );
+        assertEquals("SESSION_NOT_FOUND", exception.getBizCode());
+    }
+
+    private void assertInvalid(String json, ParserCall call) throws Exception {
+        BookingAgentException exception = assertThrows(
+                BookingAgentException.class,
+                () -> call.parse(objectMapper.readTree(json))
+        );
+        assertEquals("INVALID_INPUT", exception.getBizCode());
+    }
+
+    private interface ParserCall {
+        Object parse(com.fasterxml.jackson.databind.JsonNode node);
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/mapper/BookingAgentSessionMigrationTest.java
+++ b/src/test/java/com/petstore/bookingagent/mapper/BookingAgentSessionMigrationTest.java
@ -0,0 +1,66 @@
+package com.petstore.bookingagent.mapper;
+
+import org.h2.tools.RunScript;
+import org.junit.jupiter.api.Test;
+
+import java.io.Reader;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class BookingAgentSessionMigrationTest {
+
+    @Test
+    void migrationCreatesScopedVersionedSessionWithStateChecks() throws Exception {
+        try (Connection connection = DriverManager.getConnection(
+                "jdbc:h2:mem:booking-agent-session-migration;MODE=MySQL;DATABASE_TO_LOWER=TRUE",
+                "sa",
+                ""
+        )) {
+            try (Reader reader = Files.newBufferedReader(
+                    Path.of("db/migrations/20260802_create_booking_agent_session.sql")
+            )) {
+                RunScript.execute(connection, reader);
+            }
+
+            try (Statement statement = connection.createStatement()) {
+                statement.execute("""
+                        INSERT INTO t_booking_agent_session (
+                            session_id, customer_user_id, store_id, status, draft_json,
+                            draft_version, entry_source, input_modality,
+                            expires_at, create_time, update_time
+                        ) VALUES (
+                            'f5d7b3e2-9c25-41d3-87b0-6e4895b24d50', 99, 10, 'collecting', '{}',
+                            0, 'appointment_create', NULL,
+                            TIMESTAMP '2026-08-02 10:30:00', TIMESTAMP '2026-08-02 10:00:00',
+                            TIMESTAMP '2026-08-02 10:00:00'
+                        )
+                        """);
+                try (ResultSet rows = statement.executeQuery(
+                        "SELECT COUNT(*) FROM t_booking_agent_session WHERE customer_user_id = 99 AND store_id = 10"
+                )) {
+                    rows.next();
+                    assertEquals(1L, rows.getLong(1));
+                }
+                assertThrows(SQLException.class, () -> statement.execute("""
+                        INSERT INTO t_booking_agent_session (
+                            session_id, customer_user_id, store_id, status, draft_json,
+                            draft_version, entry_source, expires_at, create_time, update_time
+                        ) VALUES (
+                            '1ed6e952-ecb1-4b4c-9c0f-569df291cf65', 99, 10, 'booked', '{}',
+                            0, 'appointment_create',
+                            TIMESTAMP '2026-08-02 11:00:00', TIMESTAMP '2026-08-02 10:30:00',
+                            TIMESTAMP '2026-08-02 10:30:00'
+                        )
+                        """));
+            }
+        }
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentAudioValidatorTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentAudioValidatorTest.java
@ -0,0 +1,65 @@
+package com.petstore.bookingagent.service;
+
+import org.junit.jupiter.api.Test;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class BookingAgentAudioValidatorTest {
+    private final BookingAgentAudioValidator validator = new BookingAgentAudioValidator();
+
+    @Test
+    void acceptsShortWavAndNormalizesMimeType() {
+        BookingAgentAudioValidator.ValidatedAudio audio = validator.validate(wavSeconds(1), "audio/x-wav");
+
+        assertEquals("audio/wav", audio.mimeType());
+        assertEquals(1.0, audio.durationSeconds(), 0.001);
+    }
+
+    @Test
+    void rejectsMimeHeaderMismatchInvalidHeaderAndLongAudio() {
+        assertBizCode("INVALID_AUDIO", () -> validator.validate(wavSeconds(1), "audio/mpeg"));
+        assertBizCode("INVALID_AUDIO", () -> validator.validate(new byte[]{1, 2, 3}, "audio/wav"));
+        assertBizCode("INVALID_AUDIO", () -> validator.validate(wavSeconds(61), "audio/wav"));
+    }
+
+    @Test
+    void rejectsPayloadOverThreeMegabytesBeforeParsing() {
+        assertBizCode("AUDIO_TOO_LARGE", () -> validator.validate(
+                new byte[BookingAgentAudioValidator.MAX_AUDIO_BYTES + 1],
+                "audio/wav"
+        ));
+    }
+
+    private void assertBizCode(String expected, Runnable action) {
+        BookingAgentException exception = assertThrows(BookingAgentException.class, action::run);
+        assertEquals(expected, exception.getBizCode());
+    }
+
+    private byte[] wavSeconds(int seconds) {
+        int sampleRate = 16_000;
+        int channels = 1;
+        int bitsPerSample = 16;
+        int byteRate = sampleRate * channels * bitsPerSample / 8;
+        int dataSize = byteRate * seconds;
+        ByteBuffer buffer = ByteBuffer.allocate(44 + dataSize).order(ByteOrder.LITTLE_ENDIAN);
+        buffer.put("RIFF".getBytes(StandardCharsets.US_ASCII));
+        buffer.putInt(36 + dataSize);
+        buffer.put("WAVE".getBytes(StandardCharsets.US_ASCII));
+        buffer.put("fmt ".getBytes(StandardCharsets.US_ASCII));
+        buffer.putInt(16);
+        buffer.putShort((short) 1);
+        buffer.putShort((short) channels);
+        buffer.putInt(sampleRate);
+        buffer.putInt(byteRate);
+        buffer.putShort((short) (channels * bitsPerSample / 8));
+        buffer.putShort((short) bitsPerSample);
+        buffer.put("data".getBytes(StandardCharsets.US_ASCII));
+        buffer.putInt(dataSize);
+        return buffer.array();
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentContextResolverTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentContextResolverTest.java
@ -0,0 +1,187 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.config.BookingAgentRuntimeConfiguration;
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.entity.Pet;
+import com.petstore.entity.ServiceType;
+import com.petstore.entity.Store;
+import com.petstore.mapper.AppointmentMapper;
+import com.petstore.mapper.PetMapper;
+import com.petstore.mapper.ScheduleBlockMapper;
+import com.petstore.mapper.StoreMapper;
+import com.petstore.service.BookingCapacityService;
+import com.petstore.service.ServiceTypeService;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class BookingAgentContextResolverTest {
+    @Mock private PetMapper petMapper;
+    @Mock private ServiceTypeService serviceTypeService;
+    @Mock private StoreMapper storeMapper;
+    @Mock private AppointmentMapper appointmentMapper;
+    @Mock private ScheduleBlockMapper scheduleBlockMapper;
+    @Mock private BookingCapacityService bookingCapacityService;
+
+    private BookingAgentContextResolver resolver;
+    private Store store;
+    private Pet pet;
+    private ServiceType serviceType;
+
+    @BeforeEach
+    void setUp() {
+        Clock clock = Clock.fixed(
+                Instant.parse("2026-08-02T02:00:00Z"),
+                BookingAgentRuntimeConfiguration.BUSINESS_ZONE
+        );
+        resolver = new BookingAgentContextResolver(
+                petMapper,
+                serviceTypeService,
+                storeMapper,
+                appointmentMapper,
+                scheduleBlockMapper,
+                bookingCapacityService,
+                new BookingTimeConstraintResolver(),
+                clock
+        );
+        store = new Store();
+        store.setId(10L);
+        store.setName("宠小它测试店");
+        store.setBookingCapacity(1);
+        pet = new Pet();
+        pet.setId(20L);
+        pet.setName("球球");
+        pet.setPetType("狗");
+        serviceType = new ServiceType();
+        serviceType.setId(30L);
+        serviceType.setName("洗澡");
+        serviceType.setDurationMinutes(60);
+
+        when(storeMapper.findByIdAndDeletedFalse(10L)).thenReturn(Optional.of(store));
+        when(petMapper.findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(99L)).thenReturn(List.of(pet));
+        when(serviceTypeService.getByStoreId(10L)).thenReturn(List.of(serviceType));
+    }
+
+    @Test
+    void resolvesOnlyOwnedPetStoreServiceAndRealAvailableExactSlot() {
+        when(appointmentMapper.findActiveByStoreAndDateRange(eq(10L), any(), any())).thenReturn(List.of());
+        when(scheduleBlockMapper
+                .findByStoreIdAndSlotStartGreaterThanEqualAndSlotStartBeforeAndDeletedFalseOrderBySlotStartAsc(
+                        eq(10L), any(), any()
+                )).thenReturn(List.of());
+        when(bookingCapacityService.evaluateAppointment(any(), anyInt(), eq(1), eq(List.of()), eq(List.of())))
+                .thenReturn(new BookingCapacityService.CapacityResult(true, null, 0));
+
+        BookingAgentDraftState state = draft("球球", "洗澡", "明天", "14:00", "14:00");
+        BookingAgentResolution result = resolver.resolve(state, 99L);
+
+        assertEquals(BookingAgentStatus.CONFIRMABLE, result.status());
+        assertEquals(20L, state.getPetId());
+        assertEquals(30L, state.getServiceTypeId());
+        assertEquals(LocalDateTime.of(2026, 8, 3, 14, 0), state.getAppointmentTime());
+        assertEquals(LocalDateTime.of(2026, 8, 3, 15, 0), state.getAppointmentEndTime());
+        verify(petMapper).findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(99L);
+    }
+
+    @Test
+    void unavailableRequestedSlotOffersOtherRealSlotsWithoutGuessingSelection() {
+        when(appointmentMapper.findActiveByStoreAndDateRange(eq(10L), any(), any())).thenReturn(List.of());
+        when(scheduleBlockMapper
+                .findByStoreIdAndSlotStartGreaterThanEqualAndSlotStartBeforeAndDeletedFalseOrderBySlotStartAsc(
+                        eq(10L), any(), any()
+                )).thenReturn(List.of());
+        when(bookingCapacityService.evaluateAppointment(any(), anyInt(), eq(1), eq(List.of()), eq(List.of())))
+                .thenAnswer(invocation -> {
+                    LocalDateTime start = invocation.getArgument(0);
+                    return start.toLocalTime().equals(java.time.LocalTime.of(14, 0))
+                            ? new BookingCapacityService.CapacityResult(false, "接待容量已满", 1)
+                            : new BookingCapacityService.CapacityResult(true, null, 0);
+                });
+
+        BookingAgentDraftState state = draft("球球", "洗澡", "明天", "14:00", "14:00");
+        BookingAgentResolution result = resolver.resolve(state, 99L);
+
+        assertEquals(BookingAgentStatus.PROPOSING, result.status());
+        assertTrue(result.requestedSlotUnavailable());
+        assertEquals(3, result.slotOptions().size());
+        assertNull(state.getAppointmentTime());
+        assertTrue(result.slotOptions().stream().noneMatch(
+                slot -> slot.startTime().toLocalTime().equals(java.time.LocalTime.of(14, 0))
+        ));
+    }
+
+    @Test
+    void unresolvedPetStopsBeforeStoreCapacityLookup() {
+        Pet other = new Pet();
+        other.setId(21L);
+        other.setName("小白");
+        other.setPetType("猫");
+        when(petMapper.findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(99L)).thenReturn(List.of(other));
+
+        BookingAgentDraftState state = draft("球球", "洗澡", "明天", "14:00", "14:00");
+        BookingAgentResolution result = resolver.resolve(state, 99L);
+
+        assertEquals(BookingAgentStatus.COLLECTING, result.status());
+        assertNull(state.getPetId());
+        assertEquals("pet", result.quickReplies().get(0).type());
+        verify(appointmentMapper, never()).findActiveByStoreAndDateRange(any(), any(), any());
+    }
+
+    @Test
+    void duplicatePetNamesReturnDistinctNaturalLanguageChoicesWithoutIds() {
+        Pet cat = new Pet();
+        cat.setId(21L);
+        cat.setName("豆豆");
+        cat.setPetType("猫");
+        Pet dog = new Pet();
+        dog.setId(22L);
+        dog.setName("豆豆");
+        dog.setPetType("狗");
+        when(petMapper.findByOwnerUserIdAndDeletedFalseOrderByUpdateTimeDesc(99L))
+                .thenReturn(List.of(cat, dog));
+
+        BookingAgentDraftState state = draft("豆豆", "洗澡", "明天", "14:00", "14:00");
+        BookingAgentResolution result = resolver.resolve(state, 99L);
+
+        assertNull(state.getPetId());
+        assertEquals(2, result.quickReplies().size());
+        assertTrue(result.quickReplies().stream().map(BookingAgentResolution.QuickChoice::label)
+                .allMatch(label -> label.contains("豆豆") && !label.matches(".*\\d{2,}.*")));
+        assertEquals(2, result.quickReplies().stream().map(BookingAgentResolution.QuickChoice::label).distinct().count());
+    }
+
+    private BookingAgentDraftState draft(
+            String petQuery,
+            String serviceQuery,
+            String dateExpression,
+            String start,
+            String end) {
+        BookingAgentDraftState state = BookingAgentDraftState.initial(10L, store.getName());
+        state.setPetQuery(petQuery);
+        state.setServiceQuery(serviceQuery);
+        state.setDateExpression(dateExpression);
+        state.setRequestedTimeStart(start);
+        state.setRequestedTimeEnd(end);
+        return state;
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentIntentMergerTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentIntentMergerTest.java
@ -0,0 +1,70 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.provider.BookingIntentPatch;
+import org.junit.jupiter.api.Test;
+
+import java.time.LocalDateTime;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+class BookingAgentIntentMergerTest {
+    private final BookingAgentIntentMerger merger = new BookingAgentIntentMerger();
+
+    @Test
+    void newConstraintInvalidatesOnlyDependentBackendFacts() {
+        BookingAgentDraftState state = BookingAgentDraftState.initial(10L, "测试门店");
+        state.setPetQuery("球球");
+        state.setPetId(1L);
+        state.setPetName("球球");
+        state.setServiceQuery("洗澡");
+        state.setServiceTypeId(2L);
+        state.setServiceType("洗澡");
+        state.setAppointmentTime(LocalDateTime.of(2026, 8, 3, 14, 0));
+
+        BookingIntentPatch patch = new BookingIntentPatch(
+                BookingIntentPatch.SCHEMA_VERSION,
+                BookingIntentPatch.Intent.MODIFY,
+                "小白",
+                null,
+                "明天",
+                new BookingIntentPatch.TimeWindow("16:00", null),
+                null,
+                List.of(),
+                List.of(),
+                BookingIntentPatch.NextAction.RESOLVE_CONTEXT
+        );
+
+        merger.merge(state, patch);
+
+        assertEquals("小白", state.getPetQuery());
+        assertNull(state.getPetId());
+        assertEquals(2L, state.getServiceTypeId());
+        assertEquals("明天", state.getDateExpression());
+        assertEquals("16:00", state.getRequestedTimeStart());
+        assertNull(state.getAppointmentTime());
+    }
+
+    @Test
+    void clearFieldsRemovePersistedConstraintAndResolvedFact() {
+        BookingAgentDraftState state = BookingAgentDraftState.initial(10L, "测试门店");
+        state.setRemark("怕吹风机");
+        state.setServiceQuery("洗澡");
+        state.setServiceTypeId(2L);
+
+        merger.merge(state, new BookingIntentPatch(
+                BookingIntentPatch.SCHEMA_VERSION,
+                BookingIntentPatch.Intent.MODIFY,
+                null, null, null, null, null,
+                List.of(BookingIntentPatch.ClearField.REMARK, BookingIntentPatch.ClearField.SERVICE_QUERY),
+                List.of(),
+                BookingIntentPatch.NextAction.ASK
+        ));
+
+        assertNull(state.getRemark());
+        assertNull(state.getServiceQuery());
+        assertNull(state.getServiceTypeId());
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentNoAppointmentWriteContractTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentNoAppointmentWriteContractTest.java
@ -0,0 +1,33 @@
+package com.petstore.bookingagent.service;
+
+import org.junit.jupiter.api.Test;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+class BookingAgentNoAppointmentWriteContractTest {
+
+    @Test
+    void bookingAgentDomainContainsNoAppointmentWritePath() throws Exception {
+        List<Path> files;
+        try (var paths = Files.walk(Path.of("src/main/java/com/petstore/bookingagent"))) {
+            files = paths.filter(path -> path.toString().endsWith(".java")).toList();
+        }
+        String source = new StringBuilder()
+                .append(String.join("\n", files.stream().map(path -> {
+                    try {
+                        return Files.readString(path);
+                    } catch (Exception exception) {
+                        throw new IllegalStateException(exception);
+                    }
+                }).toList()))
+                .toString();
+
+        assertFalse(source.contains("AppointmentService"));
+        assertFalse(source.contains("appointmentMapper.save("));
+        assertFalse(source.contains("/confirm"));
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentRateLimiterTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentRateLimiterTest.java
@ -0,0 +1,67 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.config.BookingAgentRuntimeConfiguration;
+import org.junit.jupiter.api.Test;
+
+import java.time.Clock;
+import java.time.Duration;
+import java.time.Instant;
+import java.time.ZoneId;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+class BookingAgentRateLimiterTest {
+
+    @Test
+    void enforcesPerCustomerPerOperationTenMinuteBuckets() {
+        MutableClock clock = new MutableClock(
+                Instant.parse("2026-08-02T02:00:00Z"),
+                BookingAgentRuntimeConfiguration.BUSINESS_ZONE
+        );
+        BookingAgentRateLimiter limiter = new BookingAgentRateLimiter(clock);
+        for (int i = 0; i < 5; i++) {
+            limiter.acquire(99L, BookingAgentRateLimiter.Operation.CREATE_SESSION);
+        }
+
+        BookingAgentException exception = assertThrows(
+                BookingAgentException.class,
+                () -> limiter.acquire(99L, BookingAgentRateLimiter.Operation.CREATE_SESSION)
+        );
+        assertEquals("RATE_LIMITED", exception.getBizCode());
+
+        limiter.acquire(100L, BookingAgentRateLimiter.Operation.CREATE_SESSION);
+        limiter.acquire(99L, BookingAgentRateLimiter.Operation.SUBMIT_MESSAGE);
+        clock.advance(Duration.ofMinutes(10).plusSeconds(1));
+        limiter.acquire(99L, BookingAgentRateLimiter.Operation.CREATE_SESSION);
+    }
+
+    private static final class MutableClock extends Clock {
+        private Instant instant;
+        private final ZoneId zone;
+
+        private MutableClock(Instant instant, ZoneId zone) {
+            this.instant = instant;
+            this.zone = zone;
+        }
+
+        void advance(Duration duration) {
+            instant = instant.plus(duration);
+        }
+
+        @Override
+        public ZoneId getZone() {
+            return zone;
+        }
+
+        @Override
+        public Clock withZone(ZoneId zone) {
+            return new MutableClock(instant, zone);
+        }
+
+        @Override
+        public Instant instant() {
+            return instant;
+        }
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentServiceTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentServiceTest.java
@ -0,0 +1,328 @@
+package com.petstore.bookingagent.service;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.petstore.bookingagent.api.BookingAgentDtos;
+import com.petstore.bookingagent.config.BookingAgentProperties;
+import com.petstore.bookingagent.config.BookingAgentRuntimeConfiguration;
+import com.petstore.bookingagent.domain.BookingAgentDraftState;
+import com.petstore.bookingagent.domain.BookingAgentSession;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
+import com.petstore.bookingagent.mapper.BookingAgentSessionMapper;
+import com.petstore.bookingagent.provider.BookingIntentExtractor;
+import com.petstore.bookingagent.provider.BookingIntentPatch;
+import com.petstore.bookingagent.provider.ProviderException;
+import com.petstore.bookingagent.provider.SpeechTranscriber;
+import com.petstore.bookingagent.provider.SpeechTranscription;
+import com.petstore.entity.Store;
+import com.petstore.mapper.StoreMapper;
+import com.petstore.service.BusinessEventService;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.util.List;
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.lenient;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class BookingAgentServiceTest {
+    private static final Long CUSTOMER_ID = 99L;
+    private static final Long STORE_ID = 10L;
+    private static final String SESSION_ID = "f5d7b3e2-9c25-41d3-87b0-6e4895b24d50";
+    private static final LocalDateTime NOW = LocalDateTime.of(2026, 8, 2, 10, 0);
+
+    @Mock private BookingAgentSessionMapper sessionMapper;
+    @Mock private StoreMapper storeMapper;
+    @Mock private BookingIntentExtractor intentExtractor;
+    @Mock private SpeechTranscriber speechTranscriber;
+    @Mock private BookingAgentContextResolver contextResolver;
+    @Mock private BookingAgentAudioValidator audioValidator;
+    @Mock private BookingAgentRateLimiter rateLimiter;
+    @Mock private BusinessEventService businessEventService;
+
+    private BookingAgentProperties properties;
+    private ObjectMapper objectMapper;
+    private BookingAgentService service;
+
+    @BeforeEach
+    void setUp() {
+        properties = new BookingAgentProperties();
+        properties.setEnabled(true);
+        objectMapper = new ObjectMapper().findAndRegisterModules();
+        Clock clock = Clock.fixed(
+                Instant.parse("2026-08-02T02:00:00Z"),
+                BookingAgentRuntimeConfiguration.BUSINESS_ZONE
+        );
+        service = new BookingAgentService(
+                properties,
+                sessionMapper,
+                storeMapper,
+                intentExtractor,
+                speechTranscriber,
+                contextResolver,
+                new BookingAgentIntentMerger(),
+                new BookingAgentReplyRenderer(),
+                audioValidator,
+                rateLimiter,
+                businessEventService,
+                objectMapper,
+                clock
+        );
+        lenient().when(sessionMapper.save(any(BookingAgentSession.class))).thenAnswer(invocation -> {
+            BookingAgentSession saved = invocation.getArgument(0);
+            if (saved.getId() == null) saved.setId(500L);
+            return saved;
+        });
+    }
+
+    @Test
+    void disabledFeatureFailsBeforeTouchingStoreOrProvider() {
+        properties.setEnabled(false);
+
+        assertBizCode("AGENT_DISABLED", () -> service.createSession(CUSTOMER_ID, STORE_ID));
+
+        verify(storeMapper, never()).findByIdAndDeletedFalse(any());
+        verify(intentExtractor, never()).extract(any());
+    }
+
+    @Test
+    void createsThirtyMinuteOwnedSessionAndStartedEvent() {
+        Store store = store();
+        BookingAgentDraftState state = BookingAgentDraftState.initial(STORE_ID, store.getName());
+        BookingAgentResolution resolution = collecting(state);
+        when(storeMapper.findByIdAndDeletedFalse(STORE_ID)).thenReturn(Optional.of(store));
+        when(contextResolver.resolve(state, CUSTOMER_ID)).thenReturn(resolution);
+
+        BookingAgentDtos.SessionView view = service.createSession(CUSTOMER_ID, STORE_ID);
+
+        assertEquals(0, view.draftVersion());
+        assertEquals(NOW.plusMinutes(30), view.expiresAt());
+        assertEquals(BookingAgentStatus.COLLECTING, view.status());
+        verify(rateLimiter).acquire(CUSTOMER_ID, BookingAgentRateLimiter.Operation.CREATE_SESSION);
+        verify(businessEventService).recordBookingAgentStarted(any(BookingAgentSession.class));
+    }
+
+    @Test
+    void successfulMessageChecksVersionIncrementsAndEmitsFirstReadyEvent() throws Exception {
+        BookingAgentSession session = activeSession(BookingAgentStatus.COLLECTING, 0);
+        BookingAgentDraftState state = objectMapper.readValue(session.getDraftJson(), BookingAgentDraftState.class);
+        BookingIntentPatch patch = patch("球球", "洗澡", "明天", "14:00", "14:00");
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+        when(intentExtractor.extract(any())).thenReturn(patch);
+        when(contextResolver.resolve(any(BookingAgentDraftState.class), eq(CUSTOMER_ID)))
+                .thenAnswer(invocation -> confirmable(invocation.getArgument(0)));
+
+        BookingAgentDtos.SessionView view = service.submitMessage(
+                CUSTOMER_ID, SESSION_ID, "voice", "明天下午两点", 0
+        );
+
+        assertEquals(1, view.draftVersion());
+        assertEquals(BookingAgentStatus.CONFIRMABLE, view.status());
+        assertTrue(view.confirmable());
+        assertEquals("voice", session.getInputModality());
+        verify(businessEventService).recordBookingAgentDraftReady(session);
+        assertFalse(session.getDraftJson().contains("明天下午两点"));
+        assertFalse(session.getDraftJson().contains("petQuery"));
+        assertFalse(session.getDraftJson().contains("serviceQuery"));
+        assertFalse(session.getDraftJson().contains("dateExpression"));
+    }
+
+    @Test
+    void staleVersionDoesNotCallProviderOrMutateDraft() {
+        BookingAgentSession session = activeSession(BookingAgentStatus.COLLECTING, 2);
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+
+        assertBizCode("DRAFT_VERSION_CONFLICT", () -> service.submitMessage(
+                CUSTOMER_ID, SESSION_ID, "text", "明天", 1
+        ));
+
+        verify(intentExtractor, never()).extract(any());
+        assertEquals(2, session.getDraftVersion());
+    }
+
+    @Test
+    void missingAndOtherCustomerSessionsUseSameHiddenNotFound() {
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.empty());
+
+        assertBizCode("SESSION_NOT_FOUND", () -> service.cancel(CUSTOMER_ID, SESSION_ID));
+    }
+
+    @Test
+    void endpointDetectionMarksExpiredSessionWithoutSlidingTtl() {
+        BookingAgentSession session = activeSession(BookingAgentStatus.COLLECTING, 0);
+        session.setExpiresAt(NOW);
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+
+        assertBizCode("SESSION_EXPIRED", () -> service.submitMessage(
+                CUSTOMER_ID, SESSION_ID, "text", "明天", 0
+        ));
+
+        assertEquals(BookingAgentStatus.EXPIRED, session.resolvedStatus());
+        assertEquals(NOW, session.getExpiresAt());
+        verify(sessionMapper).save(session);
+        verify(intentExtractor, never()).extract(any());
+    }
+
+    @Test
+    void providerFailurePreservesDraftAndVersionThenRecordsLowSensitivityFallback() {
+        BookingAgentSession session = activeSession(BookingAgentStatus.COLLECTING, 3);
+        String oldDraft = session.getDraftJson();
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+        when(intentExtractor.extract(any())).thenThrow(ProviderException.timeout());
+
+        assertBizCode("AGENT_UNAVAILABLE", () -> service.submitMessage(
+                CUSTOMER_ID, SESSION_ID, "text", "明天", 3
+        ));
+
+        assertEquals(BookingAgentStatus.FALLBACK, session.resolvedStatus());
+        assertEquals(3, session.getDraftVersion());
+        assertEquals(oldDraft, session.getDraftJson());
+        verify(businessEventService).recordBookingAgentFallback(session, "llm_unavailable");
+    }
+
+    @Test
+    void handoffReturnsVerifiedDraftAndMakesSessionTerminal() {
+        BookingAgentSession session = activeSession(BookingAgentStatus.CONFIRMABLE, 4);
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+
+        BookingAgentDtos.HandoffData result = service.handoff(CUSTOMER_ID, SESSION_ID, 4);
+
+        assertEquals("booking-agent-m0", result.source());
+        assertEquals(STORE_ID, result.draft().storeId());
+        assertEquals(BookingAgentStatus.FALLBACK, session.resolvedStatus());
+        verify(businessEventService).recordBookingAgentFallback(session, "user");
+    }
+
+    @Test
+    void transcriptionUsesSessionDerivedContextButDoesNotPersistText() {
+        BookingAgentSession session = activeSession(BookingAgentStatus.COLLECTING, 0);
+        byte[] bytes = new byte[]{1, 2, 3};
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+        when(audioValidator.validate(bytes, "audio/wav"))
+                .thenReturn(new BookingAgentAudioValidator.ValidatedAudio(bytes, "audio/wav", 1));
+        when(contextResolver.speechContextTerms(CUSTOMER_ID, STORE_ID))
+                .thenReturn(List.of("球球", "洗澡"));
+        when(speechTranscriber.transcribe(any())).thenReturn(new SpeechTranscription("明天下午两点"));
+
+        BookingAgentDtos.TranscriptionData result = service.transcribe(
+                CUSTOMER_ID, SESSION_ID, bytes, "audio/wav"
+        );
+
+        assertEquals("明天下午两点", result.text());
+        assertFalse(session.getDraftJson().contains(result.text()));
+        verify(sessionMapper, never()).save(session);
+    }
+
+    @Test
+    void cancelDoesNotDependOnFeatureFlagAndCreatesNoFallbackEvent() {
+        properties.setEnabled(false);
+        BookingAgentSession session = activeSession(BookingAgentStatus.PROPOSING, 1);
+        when(sessionMapper.findOwnedForUpdate(SESSION_ID, CUSTOMER_ID)).thenReturn(Optional.of(session));
+
+        BookingAgentDtos.CancelData result = service.cancel(CUSTOMER_ID, SESSION_ID);
+
+        assertEquals(BookingAgentStatus.CANCELLED, result.status());
+        verify(businessEventService, never()).recordBookingAgentFallback(any(), any());
+    }
+
+    private BookingAgentSession activeSession(BookingAgentStatus status, int version) {
+        BookingAgentDraftState state = BookingAgentDraftState.initial(STORE_ID, "宠小它测试店");
+        BookingAgentSession session = new BookingAgentSession();
+        session.setId(500L);
+        session.setSessionId(SESSION_ID);
+        session.setCustomerUserId(CUSTOMER_ID);
+        session.setStoreId(STORE_ID);
+        session.setStatus(status);
+        session.setDraftJson(write(state));
+        session.setDraftVersion(version);
+        session.setEntrySource("appointment_create");
+        session.setExpiresAt(NOW.plusMinutes(30));
+        session.setCreateTime(NOW);
+        session.setUpdateTime(NOW);
+        return session;
+    }
+
+    private BookingAgentResolution collecting(BookingAgentDraftState state) {
+        return new BookingAgentResolution(
+                state,
+                BookingAgentStatus.COLLECTING,
+                List.of(),
+                List.of(),
+                false
+        );
+    }
+
+    private BookingAgentResolution confirmable(BookingAgentDraftState state) {
+        state.setPetId(20L);
+        state.setPetName("球球");
+        state.setPetType("狗");
+        state.setServiceTypeId(30L);
+        state.setServiceType("洗澡");
+        state.setDurationMinutes(60);
+        state.setDateConstraint(java.time.LocalDate.of(2026, 8, 3));
+        state.setAppointmentTime(LocalDateTime.of(2026, 8, 3, 14, 0));
+        state.setAppointmentEndTime(LocalDateTime.of(2026, 8, 3, 15, 0));
+        return new BookingAgentResolution(
+                state,
+                BookingAgentStatus.CONFIRMABLE,
+                List.of(),
+                List.of(),
+                false
+        );
+    }
+
+    private BookingIntentPatch patch(
+            String pet,
+            String serviceName,
+            String date,
+            String start,
+            String end) {
+        return new BookingIntentPatch(
+                BookingIntentPatch.SCHEMA_VERSION,
+                BookingIntentPatch.Intent.BOOK,
+                pet,
+                serviceName,
+                date,
+                new BookingIntentPatch.TimeWindow(start, end),
+                null,
+                List.of(),
+                List.of(),
+                BookingIntentPatch.NextAction.RESOLVE_CONTEXT
+        );
+    }
+
+    private Store store() {
+        Store store = new Store();
+        store.setId(STORE_ID);
+        store.setName("宠小它测试店");
+        return store;
+    }
+
+    private String write(BookingAgentDraftState state) {
+        try {
+            return objectMapper.writeValueAsString(state);
+        } catch (Exception exception) {
+            throw new AssertionError(exception);
+        }
+    }
+
+    private void assertBizCode(String expected, Runnable action) {
+        BookingAgentException exception = assertThrows(BookingAgentException.class, action::run);
+        assertEquals(expected, exception.getBizCode());
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingAgentSessionJanitorTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingAgentSessionJanitorTest.java
@ -0,0 +1,30 @@
+package com.petstore.bookingagent.service;
+
+import com.petstore.bookingagent.config.BookingAgentRuntimeConfiguration;
+import com.petstore.bookingagent.mapper.BookingAgentSessionMapper;
+import org.junit.jupiter.api.Test;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+
+class BookingAgentSessionJanitorTest {
+
+    @Test
+    void expiresActiveRowsAndPurgesTwentyFourHoursAfterExpiry() {
+        BookingAgentSessionMapper mapper = mock(BookingAgentSessionMapper.class);
+        Clock clock = Clock.fixed(
+                Instant.parse("2026-08-02T02:00:00Z"),
+                BookingAgentRuntimeConfiguration.BUSINESS_ZONE
+        );
+
+        new BookingAgentSessionJanitor(mapper, clock).maintainSessions();
+
+        LocalDateTime now = LocalDateTime.of(2026, 8, 2, 10, 0);
+        verify(mapper).expireActiveSessions(now);
+        verify(mapper).deleteExpiredBefore(now.minusHours(24));
+    }
+}
--- a/src/test/java/com/petstore/bookingagent/service/BookingTimeConstraintResolverTest.java
+++ b/src/test/java/com/petstore/bookingagent/service/BookingTimeConstraintResolverTest.java
@ -0,0 +1,32 @@
+package com.petstore.bookingagent.service;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.LocalDate;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+class BookingTimeConstraintResolverTest {
+    private final BookingTimeConstraintResolver resolver = new BookingTimeConstraintResolver();
+    private final LocalDate today = LocalDate.of(2026, 8, 3);
+
+    @Test
+    void resolvesFrozenRelativeAndAbsoluteForms() {
+        assertEquals(today, resolver.resolve("今天", today));
+        assertEquals(LocalDate.of(2026, 8, 4), resolver.resolve("明天", today));
+        assertEquals(LocalDate.of(2026, 8, 5), resolver.resolve("后天", today));
+        assertEquals(LocalDate.of(2026, 8, 8), resolver.resolve("本周六", today));
+        assertEquals(LocalDate.of(2026, 8, 11), resolver.resolve("下周二", today));
+        assertEquals(LocalDate.of(2026, 8, 12), resolver.resolve("8月12日", today));
+        assertEquals(LocalDate.of(2026, 8, 12), resolver.resolve("2026-08-12", today));
+    }
+
+    @Test
+    void refusesAmbiguousInvalidAndPastDates() {
+        assertNull(resolver.resolve("过几天", today));
+        assertNull(resolver.resolve("周末都行", today));
+        assertNull(resolver.resolve("2026-07-31", today));
+        assertNull(resolver.resolve("2月30日", today));
+    }
+}
--- a/src/test/java/com/petstore/service/BusinessEventServiceTest.java
+++ b/src/test/java/com/petstore/service/BusinessEventServiceTest.java
@ -1,6 +1,8 @@
 package com.petstore.service;

 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.petstore.bookingagent.domain.BookingAgentSession;
+import com.petstore.bookingagent.domain.BookingAgentStatus;
 import com.petstore.entity.Appointment;
 import com.petstore.entity.BusinessEvent;
 import com.petstore.entity.FollowUpTask;
@ -189,4 +191,36 @@ class BusinessEventServiceTest {
        assertEquals("{\"bookingOrigin\":\"follow_up\"}", event.getMetadataJson());
        assertFalse(event.getMetadataJson().contains("phone"));
    }
+
+    @Test
+    void bookingAgentFactsUseSessionAggregateAndWhitelistedMetadataOnly() {
+        BookingAgentSession session = new BookingAgentSession();
+        session.setId(500L);
+        session.setStoreId(10L);
+        session.setCustomerUserId(88L);
+        session.setEntrySource("appointment_create");
+        session.setInputModality("mixed");
+        session.setStatus(BookingAgentStatus.CONFIRMABLE);
+        session.setCreateTime(LocalDateTime.of(2026, 8, 2, 10, 0));
+        session.setUpdateTime(LocalDateTime.of(2026, 8, 2, 10, 5));
+        when(storeCustomerMapper.findFirstByStoreIdAndCustomerUserId(10L, 88L))
+                .thenReturn(Optional.empty());
+        when(businessEventMapper.findFirstByIdempotencyKey(any())).thenReturn(Optional.empty());
+        when(businessEventMapper.save(any(BusinessEvent.class))).thenAnswer(inv -> inv.getArgument(0));
+
+        BusinessEvent started = service.recordBookingAgentStarted(session);
+        BusinessEvent ready = service.recordBookingAgentDraftReady(session);
+        BusinessEvent fallback = service.recordBookingAgentFallback(session, "llm_unavailable");
+
+        assertEquals("booking_agent_session", started.getAggregateType());
+        assertEquals(500L, started.getAggregateId());
+        assertEquals("{\"entrySource\":\"appointment_create\"}", started.getMetadataJson());
+        assertEquals("{\"inputModality\":\"mixed\"}", ready.getMetadataJson());
+        assertEquals("{\"reason\":\"llm_unavailable\"}", fallback.getMetadataJson());
+        assertTrue(List.of(started, ready, fallback).stream().allMatch(event ->
+                !event.getMetadataJson().contains("球球")
+                        && !event.getMetadataJson().contains("remark")
+                        && !event.getMetadataJson().contains("token")
+        ));
+    }
 }