diff --git a/.gemini/config.yaml b/.gemini/config.yaml
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+# Disable playful or humorous responses in review comments
+have_fun: false
+
+code_review:
+  disable: false
+  # Only comment on meaningful issues to reduce noise
+  comment_severity_threshold: MEDIUM
+
+  # Prevent excessive comments on large PRs
+  max_review_comments: 50
+
+  pull_request_opened:
+    help: false
+    summary: true
+    code_review: true
+
+ignore_patterns:
+  # Gradle wrapper files
+  - "gradlew"
+  - "gradlew.bat"
+  - "gradle/wrapper/**"
+
+  # Database initialization script
+  - "src/main/resources/init.sql"
+
+  # Documentation
+  - "docs/**"
diff --git a/.gemini/styleguide.md b/.gemini/styleguide.md
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+AGENTS.md
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diff --git a/AGENTS.md b/AGENTS.md
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+# CrewWiki Backend Style Guide
+
+This file provides instructions for AI coding agents (Claude Code, Codex, etc.) working on the CrewWiki backend project.
+
+**Always respond and write comments in Korean.**
+
+---
+
+## Project Overview
+
+- **Language**: Java
+- **Framework**: Spring Boot
+- **Build tool**: Gradle
+- **Test**: JUnit 5, RestAssured, AssertJ
+
+---
+
+## 1. Package Structure
+
+Each domain must follow this layered structure:
+
+```
+{domain}/
+├── controller/
+├── dto/
+├── repository/
+└── service/
+```
+
+Shared code belongs under:
+
+```
+common/
+├── config/
+├── entity/
+├── exception/
+├── infrastructure/
+├── log/
+└── utils/
+```
+
+Do not place domain-specific logic inside `common/`.
+
+---
+
+## 2. Test Code
+
+### 2.1 Naming
+
+- `@Nested` classes must be named after the **production method** they test, in **UpperCamelCase**.
+- Test method names must follow this format:
+  - `productionMethod_success_condition`
+  - `productionMethod_fail_condition`
+
+```java
+@Nested
+class Login {
+    @Test
+    void login_success_byValidCredentials() { }
+
+    @Test
+    void login_fail_byInvalidCredentials() { }
+}
+```
+
+### 2.2 BDD Pattern
+
+```java
+// given (omit if not needed)
+// when
+// then
+```
+
+### 2.3 Fixtures
+
+Use static factory methods. Do not instantiate test objects with constructors directly.
+
+```java
+CrewDocument doc = DocumentFixture.createDefaultCrewDocument();
+```
+
+### 2.4 Test Strategy
+
+- Controller tests: use `RestAssured` when authentication/authorization is required.
+- Service tests: use `@SpringBootTest(webEnvironment = MOCK or NONE)`. Do not start Tomcat.
+- Use `assertSoftly` for multiple assertions.
+- Prefer **state verification** over behavior (mock) verification.
+- Service tests are **mandatory**. Controller tests are optional.
+
+---
+
+## 3. Naming Conventions
+
+- **Methods**: start with a verb. Do not include the entity name.
+  - Correct: `findById(Long id)`
+  - Incorrect: `getMember(Long id)`
+
+- **Path variables**: be specific.
+  - Correct: `/api/{documentId}`
+  - Incorrect: `/api/{id}`
+
+- **DTOs**: use `Request` / `Response` suffixes. `Register` / `Update` are also acceptable for mutations.
+  - Examples: `DocumentSearchResponse`, `DocumentUpdateRequest`
+
+---
+
+## 4. Object-Oriented Principles
+
+Follow these rules strictly when writing or modifying code:
+
+1. Only one level of indentation per method.
+2. No `else`. Use early returns.
+3. Wrap primitives and strings in meaningful types.
+4. One dot per line — avoid chaining across objects.
+5. No abbreviations.
+6. Keep classes small and focused.
+7. Aim to minimize instance variables per class. JPA entities and DTOs may exceed this when necessary (e.g., audit fields, associations).
+8. Wrap collections in first-class collection classes.
+9. Avoid getters and setters unless strictly needed.
+
+---
+
+## 5. Exception Handling
+
+- Do not throw generic exceptions (`RuntimeException`, `Exception`).
+- Use project-defined exception types that include an error code.
+- All error responses must include a `code` field.
+
+```json
+{
+  "code": "DOCUMENT_NOT_FOUND",
+  "message": "..."
+}
+```
+
+---
+
+## 6. Annotation Order
+
+When adding annotations, always use this order (top to bottom):
+
+1. Logging (`@Slf4j`)
+2. Lombok (`@Getter`, `@NoArgsConstructor`, `@Builder`, etc.)
+3. Spring meta (`@EntityListeners`, etc.)
+4. Spring component (`@Entity`, `@Table`, `@Service`, `@RestController`, etc.)
+
+```java
+@Slf4j
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@EntityListeners(AuditingEntityListener.class)
+@Entity
+@Table(name = "...")
+public class SampleEntity { }
+```
+
+---
+
+## 7. Domain Exposure
+
+- Entities must **not** be returned from controllers or exposed outside the service layer.
+- Use DTOs at all boundaries.
+
+```java
+// Correct
+public ApiResponse<SuccessBody<DocumentResponse>> getByUuid(...) { }
+
+// Incorrect
+public Document getByUuid(...) { }
+```
+
+---
+
+## 8. API and DTO Mapping
+
+- Each API endpoint must map to its own DTO (1:1).
+- Separate DTOs for admin and general endpoints.
+
+```
+Admin document search  →  AdminDocumentSearchResponse
+General document search  →  DocumentSearchResponse
+```
+
+---
+
+## 9. Code Style
+
+- Add one blank line before each class declaration.
+- If a method has 2 or more parameters, place each on a new line.
+- No restriction on method length; prioritize readability.
+
+---
+
+## 10. Validation Placement
+
+- **Behavior validation** (business rules, authorization): service layer.
+- **State validation** (field constraints, invariants): domain layer.
+
+---
+
+## 11. Import Rules
+
+- No wildcard imports (`import com.example.*`).
+- Follow IntelliJ IDEA default ordering.
+- Static imports are allowed.
+
+---
+
+## 12. Miscellaneous
+
+- Use `final` for fields and constants.
+- Prefer static factory methods over constructors.
+- Constants: `UPPER_SNAKE_CASE`.
+- Member ordering: `public` → `protected` → `private`. Getters go at the bottom.
+- Do not introduce Value Objects (VO) without team agreement.
+
+---
+
+## 13. DTO Policy
+
+- Use `record` for DTOs by default.
+- Use `class` only when `record` is incompatible (e.g., `@ModelAttribute` binding).
+
+---
+
+## 14. Shared Naming (Do Not Rename)
+
+These names are standardized across the project. Do not rename or create alternatives:
+
+| Type | Name |
+|------|------|
+| Paged response wrapper | `PagedResponse` |
+| Paging request | `PagingRequest` |
+| Token info response | `TokenInfoResponse` |
+| Auth tokens response | `AuthTokensResponse` |
+
+---
+
+## 15. Agent Behavior Guidelines
+
+- Before making changes, read the relevant domain's existing code to understand patterns in use.
+- Do not introduce new libraries or dependencies without explicit instruction.
+- When creating a new class, always check if a similar one already exists in `common/`.
+- When writing tests, always add a corresponding fixture if one does not exist.
+- Do not modify `build.gradle` unless explicitly asked.
+- If uncertain about a design decision, leave a `// TODO:` comment explaining the ambiguity rather than guessing.
diff --git a/CLAUDE.md b/CLAUDE.md
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+AGENTS.md
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