diff --git a/openspec/changes/add-pytest-tests/proposal.md b/openspec/changes/add-pytest-tests/proposal.md
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+# Add Pytest Tests Proposal
+
+## Why
+
+The project currently has no automated tests despite having pytest and pytest-asyncio configured in `pyproject.toml`. This creates several risks:
+- **Regression risk**: Changes to existing features (member CRUD operations, GraphQL resolvers, MCP tools, validation logic) may break functionality without detection
+- **Confidence**: Developers and AI assistants lack confidence when refactoring or adding features
+- **Documentation gap**: Tests serve as executable documentation of expected behavior
+- **Quality assurance**: No automated verification of business rules (validation, sorting, error handling)
+
+Testing is critical for:
+1. Member CRUD operations (create, read, update, delete)
+2. GraphQL API (queries, mutations, introspection)
+3. MCP server tools (6 tools connecting to GraphQL API)
+4. Validation logic (email, phone, firstName)
+5. Database operations (async SQLAlchemy patterns)
+
+## What
+
+Implement comprehensive pytest test suite covering existing features:
+
+### Test Infrastructure
+- Create `tests/` directory with proper structure (unit, integration, e2e, mcp)
+- Configure pytest fixtures for database setup (in-memory SQLite)
+- Configure async test support (pytest-asyncio already in dependencies)
+- Add conftest.py with shared fixtures
+
+### Test Coverage
+1. **Unit Tests** (`tests/unit/`)
+   - Validation logic (email, phone, firstName)
+   - Utility functions
+
+2. **Integration Tests** (`tests/integration/`)
+   - Database operations with Member model
+   - GraphQL resolvers (Query, Mutation)
+   - Error handling (MemberNotFoundError, ValidationError)
+
+3. **E2E Tests** (`tests/e2e/`)
+   - Complete GraphQL query flows
+   - Complete GraphQL mutation flows
+   - GraphQL introspection queries
+
+4. **MCP Tests** (`tests/mcp/`)
+   - MCP server tool definitions
+   - MCP tool execution (list_members, get_member, create_member, update_member)
+   - General GraphQL tools (get_graphql_schema, execute_graphql_query)
+
+### Documentation
+- Update README.md with testing instructions
+- Add "Running Tests" section
+- Add "Test Coverage" section
+- Document test organization and conventions
+
+## Impact
+
+### Breaking Changes
+None - purely additive.
+
+### New Dependencies
+None - pytest and pytest-asyncio already in dev dependencies.
+
+### Migration
+No migration needed.
+
+## Alternatives Considered
+
+1. **unittest instead of pytest**
+   - Rejected: pytest is already configured and provides better async support, fixtures, and test discovery
+
+2. **Test only critical paths**
+   - Rejected: Comprehensive testing provides better confidence and documentation
+
+3. **Skip MCP tests**
+   - Rejected: MCP server is a core component and needs testing
+
+## Success Criteria
+
+1. Test suite runs with `uv run pytest`
+2. All existing features have test coverage
+3. Tests are organized logically (unit, integration, e2e, mcp)
+4. Tests use proper fixtures for database setup
+5. README.md documents how to run tests
+6. No changes to production code (except minor fixes if bugs are found)
+
+## Related Changes
+
+None - this is the first testing implementation.
+
+## Open Questions
+
+None - the implementation is straightforward.
diff --git a/openspec/changes/add-pytest-tests/specs/project-setup/spec.md b/openspec/changes/add-pytest-tests/specs/project-setup/spec.md
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+++ b/openspec/changes/add-pytest-tests/specs/project-setup/spec.md
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+# project-setup Spec Delta
+
+## ADDED Requirements
+
+### Requirement: Automated Test Suite with Pytest
+The project SHALL provide a comprehensive test suite using pytest to verify all features and prevent regressions.
+
+#### Scenario: Run test suite successfully
+- **GIVEN** the project is set up with dependencies installed
+- **WHEN** the developer runs `uv run pytest`
+- **THEN** all tests SHALL execute
+- **AND** test results SHALL be displayed with pass/fail status
+- **AND** the command SHALL exit with code 0 if all tests pass
+
+#### Scenario: Run tests with verbose output
+- **GIVEN** the project has tests implemented
+- **WHEN** the developer runs `uv run pytest --verbose`
+- **THEN** detailed test output SHALL be displayed
+- **AND** each test name and result SHALL be shown
+
+#### Scenario: Run specific test categories
+- **GIVEN** tests are organized in subdirectories
+- **WHEN** the developer runs `uv run pytest tests/unit`
+- **THEN** only unit tests SHALL execute
+- **WHEN** the developer runs `uv run pytest tests/integration`
+- **THEN** only integration tests SHALL execute
+
+### Requirement: Test Organization Structure
+Tests SHALL be organized in a clear directory structure separating different test types.
+
+#### Scenario: Test directory structure exists
+- **GIVEN** the project repository
+- **WHEN** inspecting the directory structure
+- **THEN** a `tests/` directory SHALL exist at the project root
+- **AND** subdirectories `tests/unit/`, `tests/integration/`, `tests/e2e/`, and `tests/mcp/` SHALL exist
+- **AND** a `tests/conftest.py` file SHALL exist for shared fixtures
+
+#### Scenario: Test files follow naming convention
+- **GIVEN** test files in the `tests/` directory
+- **WHEN** examining file names
+- **THEN** all test files SHALL be named `test_*.py`
+- **AND** test file names SHALL correspond to the modules they test (e.g., `test_validation.py` for `validation.py`)
+
+### Requirement: Shared Test Fixtures
+The test suite SHALL provide reusable fixtures for common test setup via conftest.py.
+
+#### Scenario: Database fixture provides in-memory SQLite
+- **GIVEN** tests need database access
+- **WHEN** a test function requests the `db` fixture
+- **THEN** an in-memory SQLite database SHALL be created
+- **AND** the database SHALL have all tables created via Alembic migrations or direct schema creation
+- **AND** the database SHALL be cleaned up after the test completes
+
+#### Scenario: Async session fixture provides database sessions
+- **GIVEN** tests need to interact with the database
+- **WHEN** a test function requests the `async_session` fixture
+- **THEN** an async SQLAlchemy session SHALL be provided
+- **AND** the session SHALL be connected to the test database
+- **AND** the session SHALL be closed after the test completes
+
+#### Scenario: GraphQL client fixture provides test client
+- **GIVEN** tests need to make GraphQL requests
+- **WHEN** a test function requests the `graphql_client` fixture
+- **THEN** a FastAPI test client SHALL be provided
+- **AND** the client SHALL be configured to use the test database
+- **AND** the client SHALL support async GraphQL queries and mutations
+
+### Requirement: Unit Tests for Validation Logic
+Unit tests SHALL verify validation functions work correctly with valid and invalid inputs.
+
+#### Scenario: Test firstName validation with valid input
+- **GIVEN** a valid firstName "Alice"
+- **WHEN** `validate_first_name("Alice")` is called
+- **THEN** no exception SHALL be raised
+
+#### Scenario: Test firstName validation with empty string
+- **GIVEN** an empty firstName ""
+- **WHEN** `validate_first_name("")` is called
+- **THEN** a ValidationError SHALL be raised
+- **AND** the error message SHALL indicate firstName cannot be empty
+
+#### Scenario: Test email validation with valid email
+- **GIVEN** a valid email "test@example.com"
+- **WHEN** `validate_email("test@example.com")` is called
+- **THEN** no exception SHALL be raised
+
+#### Scenario: Test email validation with invalid email
+- **GIVEN** an invalid email "not-an-email"
+- **WHEN** `validate_email("not-an-email")` is called
+- **THEN** a ValidationError SHALL be raised
+- **AND** the error message SHALL indicate invalid email format
+
+#### Scenario: Test email validation with None
+- **GIVEN** email is None
+- **WHEN** `validate_email(None)` is called
+- **THEN** no exception SHALL be raised (None is allowed)
+
+#### Scenario: Test phone validation with valid E.164 number
+- **GIVEN** a valid phone "+41791234567"
+- **WHEN** `validate_phone("+41791234567")` is called
+- **THEN** no exception SHALL be raised
+
+#### Scenario: Test phone validation with invalid number
+- **GIVEN** an invalid phone "123"
+- **WHEN** `validate_phone("123")` is called
+- **THEN** a ValidationError SHALL be raised
+
+#### Scenario: Test phone validation with None
+- **GIVEN** phone is None
+- **WHEN** `validate_phone(None)` is called
+- **THEN** no exception SHALL be raised (None is allowed)
+
+### Requirement: Integration Tests for Member Model
+Integration tests SHALL verify database operations with the Member model.
+
+#### Scenario: Create member with minimal data
+- **GIVEN** a test database session
+- **WHEN** a Member is created with only firstName="Alice"
+- **THEN** the member SHALL be persisted to the database
+- **AND** the member SHALL have an auto-generated ID
+- **AND** created_at and updated_at timestamps SHALL be populated
+- **AND** all optional fields SHALL be None
+
+#### Scenario: Create member with complete data
+- **GIVEN** a test database session
+- **WHEN** a Member is created with all fields populated
+- **THEN** the member SHALL be persisted with all data
+- **AND** all fields SHALL match the provided values
+
+#### Scenario: Member timestamps are set correctly
+- **GIVEN** a newly created member
+- **THEN** created_at SHALL be set to current time
+- **AND** updated_at SHALL be set to current time
+- **AND** created_at SHALL equal updated_at for new members
+
+### Requirement: Integration Tests for GraphQL Queries
+Integration tests SHALL verify GraphQL query resolvers return correct data.
+
+#### Scenario: Query single member by ID
+- **GIVEN** a member exists with ID 1
+- **WHEN** the `member(id: 1)` query is executed
+- **THEN** the member data SHALL be returned
+- **AND** all requested fields SHALL match the database record
+
+#### Scenario: Query member with non-existent ID
+- **GIVEN** no member exists with ID 999
+- **WHEN** the `member(id: 999)` query is executed
+- **THEN** None SHALL be returned
+- **AND** no error SHALL be raised
+
+#### Scenario: List all members
+- **GIVEN** multiple members exist in the database
+- **WHEN** the `members` query is executed
+- **THEN** an array of all members SHALL be returned
+- **AND** members SHALL be sorted by last_name (nulls last), then first_name
+
+#### Scenario: List members when database is empty
+- **GIVEN** no members exist in the database
+- **WHEN** the `members` query is executed
+- **THEN** an empty array SHALL be returned
+
+### Requirement: Integration Tests for GraphQL Mutations
+Integration tests SHALL verify GraphQL mutation resolvers create, update, and delete members correctly.
+
+#### Scenario: Create member with minimal data
+- **GIVEN** CreateMemberInput with only firstName="Bob"
+- **WHEN** the `createMember` mutation is executed
+- **THEN** a new member SHALL be created in the database
+- **AND** the member SHALL have firstName="Bob"
+- **AND** all optional fields SHALL be None
+- **AND** the mutation SHALL return the created member with ID
+
+#### Scenario: Create member with complete data
+- **GIVEN** CreateMemberInput with all fields populated
+- **WHEN** the `createMember` mutation is executed
+- **THEN** a new member SHALL be created with all data
+- **AND** all fields SHALL match the input
+
+#### Scenario: Create member with invalid email
+- **GIVEN** CreateMemberInput with email="not-an-email"
+- **WHEN** the `createMember` mutation is executed
+- **THEN** a ValidationError SHALL be raised
+- **AND** no database record SHALL be created
+
+#### Scenario: Update member successfully
+- **GIVEN** a member exists with ID 1
+- **WHEN** the `updateMember` mutation is executed with id=1 and email="new@example.com"
+- **THEN** the member's email SHALL be updated to "new@example.com"
+- **AND** the updated_at timestamp SHALL be refreshed
+- **AND** all other fields SHALL remain unchanged
+
+#### Scenario: Update member with non-existent ID
+- **GIVEN** no member exists with ID 999
+- **WHEN** the `updateMember` mutation is executed with id=999
+- **THEN** a MemberNotFoundError SHALL be raised
+- **AND** the error message SHALL indicate member not found
+
+#### Scenario: Delete member successfully
+- **GIVEN** a member exists with ID 1
+- **WHEN** the `deleteMember` mutation is executed with id=1
+- **THEN** the member SHALL be removed from the database
+- **AND** the mutation SHALL return true
+- **AND** subsequent queries for that member SHALL return None
+
+#### Scenario: Delete member with non-existent ID
+- **GIVEN** no member exists with ID 999
+- **WHEN** the `deleteMember` mutation is executed with id=999
+- **THEN** a MemberNotFoundError SHALL be raised
+
+### Requirement: E2E Tests for GraphQL API
+End-to-end tests SHALL verify complete GraphQL request/response flows over HTTP.
+
+#### Scenario: Execute GraphQL query via HTTP POST
+- **GIVEN** the FastAPI application with GraphQL endpoint
+- **WHEN** a POST request is sent to /graphql with a query
+- **THEN** the query SHALL be executed
+- **AND** a JSON response SHALL be returned with data or errors
+
+#### Scenario: GraphQL introspection query
+- **GIVEN** the GraphQL API is running
+- **WHEN** an introspection query for __schema is executed
+- **THEN** the complete schema SHALL be returned
+- **AND** all types, queries, and mutations SHALL be included
+
+#### Scenario: GraphQL type introspection
+- **GIVEN** the GraphQL API is running
+- **WHEN** an introspection query for __type(name: "Member") is executed
+- **THEN** the Member type definition SHALL be returned
+- **AND** all fields with their types SHALL be included
+
+### Requirement: MCP Server Tests
+Tests SHALL verify MCP server tool definitions and execution.
+
+#### Scenario: MCP server initializes successfully
+- **GIVEN** a valid CLUBBER_API_URL
+- **WHEN** the MCP server is instantiated
+- **THEN** the server SHALL initialize without errors
+- **AND** the GraphQL client SHALL be configured
+
+#### Scenario: List tools returns all 6 tools
+- **GIVEN** an initialized MCP server
+- **WHEN** `list_tools()` is called
+- **THEN** 6 tools SHALL be returned
+- **AND** tools SHALL include: list_members, get_member, create_member, update_member, get_graphql_schema, execute_graphql_query
+
+#### Scenario: Execute list_members tool
+- **GIVEN** members exist in the database
+- **WHEN** the `list_members` tool is invoked
+- **THEN** a formatted list of all members SHALL be returned
+
+#### Scenario: Execute get_member tool
+- **GIVEN** a member exists with ID 1
+- **WHEN** the `get_member` tool is invoked with id=1
+- **THEN** the member's data SHALL be returned as formatted text
+
+#### Scenario: Execute create_member tool
+- **GIVEN** valid member input data
+- **WHEN** the `create_member` tool is invoked
+- **THEN** a new member SHALL be created via the GraphQL API
+- **AND** the created member data SHALL be returned
+
+#### Scenario: Execute get_graphql_schema tool
+- **GIVEN** the GraphQL API is accessible
+- **WHEN** the `get_graphql_schema` tool is invoked
+- **THEN** the complete schema SHALL be retrieved via introspection
+- **AND** formatted schema information SHALL be returned
+
+#### Scenario: Execute execute_graphql_query tool with simple query
+- **GIVEN** a valid GraphQL query string
+- **WHEN** the `execute_graphql_query` tool is invoked
+- **THEN** the query SHALL be executed against the API
+- **AND** formatted JSON results SHALL be returned
+
+#### Scenario: Execute execute_graphql_query tool with variables
+- **GIVEN** a GraphQL query with variables
+- **WHEN** the `execute_graphql_query` tool is invoked with query and variables
+- **THEN** the query SHALL be executed with variable substitution
+- **AND** results SHALL be returned
+
+### Requirement: Test Documentation in README
+The README SHALL document how to run tests and understand test organization.
+
+#### Scenario: README contains test running instructions
+- **GIVEN** the README.md file
+- **WHEN** reading the documentation
+- **THEN** a "Running Tests" section SHALL exist
+- **AND** the section SHALL document the `uv run pytest` command
+- **AND** examples of running specific test categories SHALL be provided
+
+#### Scenario: README documents test organization
+- **GIVEN** the README.md file
+- **WHEN** reading the documentation
+- **THEN** a "Test Organization" section SHALL exist
+- **AND** the section SHALL explain the tests/ directory structure
+- **AND** the section SHALL describe unit, integration, e2e, and mcp test categories
diff --git a/openspec/changes/add-pytest-tests/tasks.md b/openspec/changes/add-pytest-tests/tasks.md
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@@ -0,0 +1,102 @@
+# Implementation Tasks: add-pytest-tests
+
+## 1. Test Infrastructure Setup
+
+- [ ] Create `tests/` directory structure
+  - [ ] `tests/unit/` for pure logic tests
+  - [ ] `tests/integration/` for database and resolver tests
+  - [ ] `tests/e2e/` for full API tests
+  - [ ] `tests/mcp/` for MCP server tests
+- [ ] Create `tests/conftest.py` with shared fixtures
+  - [ ] Database fixture (in-memory SQLite)
+  - [ ] Async session fixture
+  - [ ] Test client fixture for FastAPI/GraphQL
+- [ ] Create `tests/__init__.py`
+
+## 2. Unit Tests
+
+- [ ] `tests/unit/test_validation.py`
+  - [ ] Test `validate_first_name()` with valid input
+  - [ ] Test `validate_first_name()` with empty string
+  - [ ] Test `validate_first_name()` with whitespace only
+  - [ ] Test `validate_email()` with valid emails
+  - [ ] Test `validate_email()` with invalid emails
+  - [ ] Test `validate_email()` with None (should pass)
+  - [ ] Test `validate_email()` with empty string (should pass)
+  - [ ] Test `validate_phone()` with valid E.164 numbers
+  - [ ] Test `validate_phone()` with invalid numbers
+  - [ ] Test `validate_phone()` with None (should pass)
+  - [ ] Test `validate_phone()` with empty string (should pass)
+
+## 3. Integration Tests - Database
+
+- [ ] `tests/integration/test_member_model.py`
+  - [ ] Test creating member with minimal data (firstName only)
+  - [ ] Test creating member with complete data
+  - [ ] Test member timestamps (created_at, updated_at)
+  - [ ] Test member __repr__
+
+## 4. Integration Tests - GraphQL Resolvers
+
+- [ ] `tests/integration/test_member_queries.py`
+  - [ ] Test `member(id)` query with existing member
+  - [ ] Test `member(id)` query with non-existent ID (returns None)
+  - [ ] Test `members` query with multiple members
+  - [ ] Test `members` query returns empty array when no members
+  - [ ] Test `members` sorting (last name nulls last, then first name)
+
+- [ ] `tests/integration/test_member_mutations.py`
+  - [ ] Test `createMember` with minimal data (firstName only)
+  - [ ] Test `createMember` with complete data
+  - [ ] Test `createMember` with invalid email (validation error)
+  - [ ] Test `createMember` with invalid phone (validation error)
+  - [ ] Test `createMember` with empty firstName (validation error)
+  - [ ] Test `updateMember` successfully updates fields
+  - [ ] Test `updateMember` with non-existent ID (MemberNotFoundError)
+  - [ ] Test `updateMember` with partial data (only updates provided fields)
+  - [ ] Test `updateMember` with invalid email (validation error)
+  - [ ] Test `deleteMember` successfully deletes member
+  - [ ] Test `deleteMember` with non-existent ID (MemberNotFoundError)
+
+## 5. E2E Tests - GraphQL API
+
+- [ ] `tests/e2e/test_graphql_api.py`
+  - [ ] Test complete query flow (list members via HTTP)
+  - [ ] Test complete mutation flow (create member via HTTP)
+  - [ ] Test GraphQL introspection query (__schema)
+  - [ ] Test GraphQL type introspection (__type)
+  - [ ] Test error responses (400 for validation errors)
+
+## 6. MCP Server Tests
+
+- [ ] `tests/mcp/test_mcp_server.py`
+  - [ ] Test MCP server initialization
+  - [ ] Test `list_tools()` returns 6 tools
+  - [ ] Test `list_members` tool execution
+  - [ ] Test `get_member` tool execution
+  - [ ] Test `get_member` with non-existent ID
+  - [ ] Test `create_member` tool execution
+  - [ ] Test `update_member` tool execution
+  - [ ] Test `get_graphql_schema` tool execution
+  - [ ] Test `execute_graphql_query` tool with simple query
+  - [ ] Test `execute_graphql_query` tool with variables
+  - [ ] Test error handling when API is unavailable
+
+## 7. Documentation
+
+- [ ] Update README.md
+  - [ ] Add "Running Tests" section
+  - [ ] Add test command examples
+  - [ ] Add "Test Organization" section
+  - [ ] Document test coverage goals
+
+## 8. Validation
+
+- [ ] Run `uv run pytest` and verify all tests pass
+- [ ] Run `uv run pytest --verbose` for detailed output
+- [ ] Run `uv run pytest tests/unit` to test unit tests
+- [ ] Run `uv run pytest tests/integration` to test integration tests
+- [ ] Run `uv run pytest tests/e2e` to test e2e tests
+- [ ] Run `uv run pytest tests/mcp` to test MCP tests
+- [ ] Verify no changes to production code (except bug fixes if found)
+- [ ] Run `openspec validate add-pytest-tests --strict`