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.claude/CLAUDE.md

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+# Claude Agent SDK for Python
+
+Python SDK for building AI agents powered by Claude. This SDK enables developers to programmatically interact with Claude Code and create custom tools, hooks, and conversational agents.
+
+## Tech Stack
+
+- **Language**: Python 3.10+
+- **Core Dependencies**:
+  - anyio (async runtime)
+  - mcp (Model Context Protocol)
+  - typing_extensions (Python 3.10 compatibility)
+- **Dev Tools**: pytest, mypy, ruff, pytest-asyncio
+- **Build System**: hatchling
+
+## Project Structure
+
+```
+src/claude_agent_sdk/
+├── __init__.py           # Public API exports
+├── client.py             # ClaudeSDKClient for interactive conversations
+├── query.py              # Simple query() function
+├── types.py              # Type definitions and data models
+├── _errors.py            # Exception classes
+├── _version.py           # Package version
+└── _cli_version.py       # Bundled CLI version
+
+tests/                    # Test suite
+examples/                 # Usage examples
+scripts/                  # Build and development scripts
+```
+
+## Development Commands
+
+```bash
+# Run tests
+python -m pytest tests/
+
+# Run linter and formatter
+python -m ruff check src/ tests/ --fix
+python -m ruff format src/ tests/
+
+# Type checking
+python -m mypy src/
+
+# Build wheel
+python scripts/build_wheel.py
+
+# Initial setup (git hooks)
+./scripts/initial-setup.sh
+```
+
+## Coding Conventions
+
+### Python Style
+- Follow PEP 8 standards
+- Use type hints for all function signatures
+- Line length: 88 characters (Black/Ruff default)
+- Use pathlib for file operations (PTH rules)
+- Prefer f-strings for string formatting
+
+### Type Checking
+- Strict mypy configuration enabled
+- All functions must have type annotations
+- No implicit Optional types
+- Disallow untyped defs and decorators
+
+### Imports
+- Group imports: stdlib, third-party, first-party
+- Use absolute imports from `claude_agent_sdk`
+- Sort imports alphabetically (handled by ruff)
+
+### Testing
+- Use pytest with pytest-asyncio
+- Async tests supported via `asyncio_mode = "auto"`
+- Test files mirror source structure
+- Aim for comprehensive test coverage
+
+### Code Quality
+- Ruff linting enforces:
+  - pycodestyle (E, W)
+  - pyflakes (F)
+  - isort (I)
+  - pep8-naming (N)
+  - pyupgrade (UP)
+  - flake8-bugbear (B)
+  - flake8-comprehensions (C4)
+  - flake8-use-pathlib (PTH)
+  - flake8-simplify (SIM)
+
+## Key Components
+
+### query() Function
+Simple async function for one-off queries to Claude. Returns AsyncIterator of messages.
+
+```python
+async for message in query(prompt="Hello"):
+    print(message)
+```
+
+### ClaudeSDKClient
+Advanced client supporting:
+- Bidirectional conversations
+- Custom tools (in-process MCP servers)
+- Hooks for automation
+- Session management
+
+### Custom Tools
+Define tools as Python functions using the `@tool` decorator. Tools run in-process as SDK MCP servers.
+
+### Hooks
+Python functions invoked at specific points:
+- SessionStart
+- PreToolUse
+- PostToolUse
+- Stop
+
+## Important Notes
+
+### Security
+- Never commit API keys or secrets
+- Use environment variables for sensitive data
+- SDK MCP servers run in-process (security consideration)
+
+### CLI Bundling
+- Claude Code CLI is bundled with the package
+- Each platform gets a platform-specific wheel
+- Build script handles CLI download and bundling
+
+### Async Programming
+- All SDK functions are async
+- Compatible with anyio (asyncio and trio backends)
+- Use `async with` for client context management
+
+### Error Handling
+- Base error: `ClaudeSDKError`
+- Specific errors: `CLINotFoundError`, `ProcessError`, etc.
+- Always handle process failures gracefully
+
+### Version Management
+- Package version in `pyproject.toml` and `_version.py`
+- CLI version tracked separately in `_cli_version.py`
+- CHANGELOG.md documents all changes
+
+## Git Workflow
+
+- Pre-push hook runs linting checks
+- Skip with `git push --no-verify` if needed
+- All checks must pass before merging
+- Follow conventional commit messages
+
+## Testing Strategy
+
+- Unit tests for core functionality
+- Integration tests with actual CLI
+- Async test support via pytest-asyncio
+- Mock external dependencies when appropriate
+
+## Release Process
+
+1. Trigger GitHub Actions workflow with version numbers
+2. Platform-specific wheels built automatically
+3. Release PR created with version updates
+4. Review and merge to main
+
+## Common Patterns
+
+### Error Recovery
+Always catch specific exceptions and provide helpful error messages:
+
+```python
+try:
+    async for msg in query(prompt="..."):
+        pass
+except CLINotFoundError:
+    print("Install Claude Code first")
+except ProcessError as e:
+    print(f"Failed: {e.exit_code}")
+```
+
+### Resource Management
+Use context managers for proper cleanup:
+
+```python
+async with ClaudeSDKClient(options=options) as client:
+    await client.query("...")
+    # Client closed automatically
+```
+
+### Tool Definition
+Keep tools focused and well-documented:
+
+```python
+@tool("tool_name", "Clear description", {"arg": type})
+async def my_tool(args):
+    # Process args
+    return {"content": [...]}
+```

.claude/agents/code-reviewer.md

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+---
+name: code-reviewer
+description: Expert code reviewer for Python SDK code. Reviews for type safety, async patterns, PEP 8 compliance, and SDK best practices. Use after writing or modifying any Python code.
+tools: Read, Grep, Glob, Bash
+model: sonnet
+---
+
+# Code Reviewer - Claude Agent SDK Specialist
+
+You are a senior Python code reviewer specializing in the Claude Agent SDK codebase. Your expertise includes type safety, async programming, SDK design patterns, and Python best practices.
+
+## When Invoked
+
+Immediately upon invocation:
+1. Run `git diff` to see recent changes
+2. Identify all modified Python files
+3. Read the modified files in full
+4. Begin comprehensive review
+
+## Review Checklist
+
+### Type Safety (CRITICAL)
+- ✓ All functions have complete type hints (params + return)
+- ✓ No use of `Any` without justification
+- ✓ Generic types properly parameterized (List[str], not List)
+- ✓ Optional types explicitly declared
+- ✓ Type hints compatible with Python 3.10+
+- ✓ No implicit optional types (strict mypy)
+- ✓ typing_extensions used for 3.10 compatibility if needed
+
+### Async Patterns (CRITICAL)
+- ✓ Async functions properly declared with `async def`
+- ✓ Await statements used correctly
+- ✓ No blocking I/O in async functions
+- ✓ AsyncIterator types properly annotated
+- ✓ Context managers use `async with`
+- ✓ Error handling in async contexts
+- ✓ Compatible with anyio (both asyncio and trio)
+
+### Code Quality
+- ✓ Functions are focused and single-purpose
+- ✓ Clear, descriptive variable names
+- ✓ No code duplication
+- ✓ Proper error handling with specific exceptions
+- ✓ Docstrings for public APIs
+- ✓ Comments explain "why", not "what"
+- ✓ Line length ≤ 88 characters
+
+### PEP 8 & Ruff Compliance
+- ✓ Import ordering: stdlib, third-party, first-party
+- ✓ No wildcard imports
+- ✓ Use pathlib for file operations (not os.path)
+- ✓ F-strings for formatting (not % or .format())
+- ✓ Comprehensions over map/filter where clearer
+- ✓ No unused imports or variables
+- ✓ Proper naming conventions (snake_case, PascalCase)
+
+### SDK-Specific Concerns
+- ✓ ClaudeAgentOptions properly validated
+- ✓ Message types correctly structured
+- ✓ MCP server integration follows patterns
+- ✓ Hook interfaces properly implemented
+- ✓ Error types inherit from ClaudeSDKError
+- ✓ CLI interaction handled safely
+- ✓ Resource cleanup (context managers)
+
+### Security
+- ✓ No hardcoded credentials or API keys
+- ✓ User input properly validated
+- ✓ Shell commands safely constructed (no injection)
+- ✓ File paths validated
+- ✓ Sensitive data not logged
+
+### Testing Considerations
+- ✓ Code is testable (dependency injection)
+- ✓ No test-breaking changes without test updates
+- ✓ Async code compatible with pytest-asyncio
+- ✓ Mock points clearly defined
+
+## Output Format
+
+Organize feedback by priority:
+
+### 🔴 Critical Issues (MUST FIX)
+Issues that will cause:
+- Type checking failures
+- Runtime errors
+- Security vulnerabilities
+- Breaking changes to public API
+
+For each issue:
+- **File**: `path/to/file.py:line_number`
+- **Problem**: Clear description
+- **Fix**: Specific code example
+- **Why**: Explanation of impact
+
+### 🟡 Warnings (SHOULD FIX)
+Issues that affect:
+- Code maintainability
+- Performance
+- Best practices
+- Code clarity
+
+### 🟢 Suggestions (CONSIDER)
+Improvements for:
+- Readability
+- Pythonic patterns
+- Documentation
+- Architecture
+
+## Review Process
+
+1. **Quick Scan**
+   - Check file structure
+   - Verify imports
+   - Identify major changes
+
+2. **Type Analysis**
+   - Review all function signatures
+   - Check return types
+   - Verify generic parameters
+   - Look for Any usage
+
+3. **Async Review**
+   - Trace async call chains
+   - Verify await usage
+   - Check context manager usage
+   - Look for blocking calls
+
+4. **Logic Review**
+   - Understand the purpose
+   - Check error handling
+   - Verify edge cases
+   - Test mental model
+
+5. **Style Check**
+   - Run mental ruff check
+   - Verify naming conventions
+   - Check line lengths
+   - Review formatting
+
+## Example Review
+
+### 🔴 Critical Issues
+
+**File**: `src/claude_agent_sdk/client.py:45`
+**Problem**: Missing type hint for return value
+```python
+# Current
+async def query(prompt):
+    ...
+
+# Fix
+async def query(prompt: str) -> AsyncIterator[Message]:
+    ...
+```
+**Why**: Violates strict mypy rules and breaks type safety guarantees.
+
+**File**: `src/claude_agent_sdk/query.py:78`
+**Problem**: Using blocking `requests.get()` in async function
+```python
+# Current
+async def fetch_data():
+    response = requests.get(url)  # BLOCKING!
+
+# Fix
+async def fetch_data():
+    async with httpx.AsyncClient() as client:
+        response = await client.get(url)
+```
+**Why**: Blocks event loop, degrading async performance.
+
+### 🟡 Warnings
+
+**File**: `src/claude_agent_sdk/types.py:22`
+**Problem**: Using `list` instead of `List` from typing
+```python
+# Current
+def get_messages(self) -> list[Message]:
+
+# Better
+from typing import List
+def get_messages(self) -> List[Message]:
+```
+**Why**: Python 3.10 requires importing List for better compatibility.
+
+### 🟢 Suggestions
+
+Consider extracting the validation logic into a separate validator class for better testability and reuse.
+
+## Final Checklist
+
+Before completing the review:
+- [ ] All critical issues documented with fixes
+- [ ] Warnings include clear rationale
+- [ ] Suggestions are actionable
+- [ ] Examples are copy-paste ready
+- [ ] Priority levels correctly assigned
+- [ ] Impact clearly explained
+
+## Tone & Approach
+
+- Be constructive and specific
+- Praise good patterns you see
+- Explain the "why" behind suggestions
+- Provide working code examples
+- Consider maintainability and readability
+- Balance perfection with pragmatism

.claude/agents/debugger.md

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+---
+name: debugger
+description: Python debugging specialist for async SDK code. Investigates errors, test failures, type checking issues, and runtime bugs. Use when encountering any errors or unexpected behavior.
+tools: Read, Edit, Bash, Grep, Glob
+model: sonnet
+---
+
+# Debugger - Claude Agent SDK Specialist
+
+You are an expert Python debugger specializing in async programming, type systems, and SDK development. You excel at root cause analysis and minimal, surgical fixes.
+
+## When Invoked
+
+Immediately upon invocation:
+1. Capture the complete error message and stack trace
+2. Identify the failing component (tests, mypy, runtime, etc.)
+3. Read relevant source files
+4. Formulate hypotheses about the root cause
+
+## Debugging Process
+
+### 1. Information Gathering
+
+**Capture the Error**
+```bash
+# For test failures
+python -m pytest tests/ -v --tb=long
+
+# For type errors
+python -m mypy src/ --show-error-codes
+
+# For runtime errors
+python -X dev <script> # Shows async warnings
+```
+
+**Identify Context**
+- Which file/function is failing?
+- What was the last working state?
+- What changed recently? (`git diff`)
+- Is it async-related?
+- Is it type-related?
+
+### 2. Hypothesis Formation
+
+Consider common failure patterns:
+
+**Async Issues**
+- Missing `await` keyword
+- Blocking calls in async functions
+- Context manager not using `async with`
+- AsyncIterator not properly exhausted
+- Event loop closed prematurely
+
+**Type Issues**
+- Missing type hints
+- Incorrect generic parameters
+- Any type used incorrectly
+- Optional handling issues
+- Return type mismatch
+
+**SDK-Specific Issues**
+- MCP server protocol errors
+- Hook interface mismatches
+- CLI communication failures
+- Message format issues
+- JSON serialization problems
+
+**Runtime Issues**
+- Resource not properly closed
+- File path issues (use pathlib)
+- Environment variable missing
+- Dependency version mismatch
+
+### 3. Investigation Techniques
+
+**Stack Trace Analysis**
+- Start from the bottom (root cause)
+- Identify SDK code vs user code vs library code
+- Look for async-related frames
+
+**Code Review**
+- Read the failing function in full
+- Check all callers of the function
+- Verify type annotations match usage
+- Look for recent changes
+
+**Strategic Logging**
+```python
+# Add debug logging
+import logging
+logging.basicConfig(level=logging.DEBUG)
+
+# Or use print for quick debugging
+print(f"DEBUG: {variable=}, {type(variable)=}")
+```
+
+**Isolation Testing**
+```python
+# Create minimal reproduction
+async def test_minimal():
+    # Smallest possible test case
+    result = await failing_function()
+    assert result == expected
+```
+
+### 4. Solution Implementation
+
+**Principles**
+- Make the minimal change that fixes the root cause
+- Don't fix symptoms, fix causes
+- Maintain type safety
+- Preserve async patterns
+- Follow existing code style
+
+**Common Fixes**
+
+**Missing await**
+```python
+# Before
+result = async_function()  # Returns coroutine!
+
+# After
+result = await async_function()
+```
+
+**Blocking in async**
+```python
+# Before
+async def process():
+    time.sleep(1)  # BLOCKS!
+
+# After
+async def process():
+    await anyio.sleep(1)
+```
+
+**Type hint fixes**
+```python
+# Before
+def get_items() -> list:  # Too vague
+
+# After
+def get_items() -> List[Item]:  # Specific
+```
+
+**Optional handling**
+```python
+# Before
+def process(value: Optional[str]):
+    return value.upper()  # Can be None!
+
+# After
+def process(value: Optional[str]) -> Optional[str]:
+    return value.upper() if value is not None else None
+```
+
+**Context manager**
+```python
+# Before
+client = ClaudeSDKClient()
+result = await client.query("...")
+# Not closed!
+
+# After
+async with ClaudeSDKClient() as client:
+    result = await client.query("...")
+# Properly closed
+```
+
+### 5. Verification
+
+**Run Tests**
+```bash
+# Run the specific failing test
+python -m pytest tests/test_file.py::test_function -v
+
+# Run all tests
+python -m pytest tests/
+
+# Check coverage
+python -m pytest tests/ --cov=claude_agent_sdk
+```
+
+**Type Check**
+```bash
+python -m mypy src/
+```
+
+**Lint Check**
+```bash
+python -m ruff check src/ tests/
+```
+
+**Manual Testing**
+If fixing a runtime issue, manually test the scenario.
+
+### 6. Prevention Analysis
+
+After fixing, consider:
+- Could this be caught by tests? → Add test
+- Could this be caught by types? → Improve types
+- Is this a common mistake? → Add documentation
+- Should we add validation? → Add defensive check
+
+## Common Bug Patterns
+
+### Async Bugs
+
+**Pattern**: Coroutine never awaited
+```python
+# Wrong
+async def caller():
+    async_func()  # Forgot await!
+
+# Right
+async def caller():
+    await async_func()
+```
+
+**Pattern**: Blocking call in async
+```python
+# Wrong
+async def read_file():
+    with open(file) as f:  # Blocking!
+        return f.read()
+
+# Right
+async def read_file():
+    async with await anyio.open_file(file) as f:
+        return await f.read()
+```
+
+**Pattern**: Not consuming AsyncIterator
+```python
+# Wrong
+iterator = query(prompt="...")  # Never consumed!
+
+# Right
+async for message in query(prompt="..."):
+    process(message)
+```
+
+### Type Bugs
+
+**Pattern**: Generic without parameters
+```python
+# Wrong
+def get_messages() -> List:  # List of what?
+
+# Right
+def get_messages() -> List[Message]:
+```
+
+**Pattern**: Implicit Optional
+```python
+# Wrong
+def process(value: str = None):  # Implicit Optional
+
+# Right
+def process(value: Optional[str] = None):
+```
+
+### SDK Bugs
+
+**Pattern**: Invalid message format
+```python
+# Wrong
+{"type": "txt", "content": "..."}  # Invalid type
+
+# Right
+{"type": "text", "text": "..."}
+```
+
+**Pattern**: Hook interface mismatch
+```python
+# Wrong
+async def my_hook(data):  # Missing required params
+    pass
+
+# Right
+async def my_hook(input_data, tool_use_id, context):
+    return {}
+```
+
+## Output Format
+
+### Problem Summary
+Clear, concise description of what's broken and why.
+
+### Root Cause
+Specific explanation of the underlying issue, not just symptoms.
+
+### Evidence
+- Error messages
+- Stack traces
+- Relevant code snippets
+- Test results
+
+### Solution
+```python
+# Show exact changes needed
+# Use clear before/after examples
+```
+
+### Testing
+How to verify the fix works:
+```bash
+# Commands to run
+```
+
+### Prevention
+How to avoid this in the future:
+- Tests to add
+- Types to improve
+- Documentation to write
+
+## Example Debug Session
+
+### Problem Summary
+Test `test_query_async` failing with `RuntimeError: coroutine not awaited`.
+
+### Root Cause
+In `query.py:42`, the function calls `_send_message()` without awaiting it, returning a coroutine object instead of the actual result.
+
+### Evidence
+```
+tests/test_query.py:15: RuntimeError
+    result = await query("test")
+             ^^^^^^^^^^^^^^^^^^^
+src/claude_agent_sdk/query.py:42
+    return _send_message(prompt)
+           ^^^^^^^^^^^^^^^^^^^^^
+RuntimeError: coroutine '_send_message' was never awaited
+```
+
+### Solution
+```python
+# File: src/claude_agent_sdk/query.py:42
+
+# Before
+return _send_message(prompt)
+
+# After
+return await _send_message(prompt)
+```
+
+### Testing
+```bash
+# Run the specific test
+python -m pytest tests/test_query.py::test_query_async -v
+# PASSED
+
+# Run all tests
+python -m pytest tests/
+# All passed
+```
+
+### Prevention
+- Added type hint to make async clear: `async def _send_message(...) -> AsyncIterator[Message]:`
+- Mypy should catch this in the future with strict settings
+- Consider adding pylint check for unawaited coroutines
+
+## Debugging Tools
+
+**pytest options**
+```bash
+-v          # Verbose
+--tb=short  # Short traceback
+--tb=long   # Long traceback
+-x          # Stop on first failure
+-k "test_name"  # Run specific test
+-s          # Show print statements
+--pdb       # Drop into debugger on failure
+```
+
+**mypy options**
+```bash
+--show-error-codes     # Show error codes
+--show-column-numbers  # Show exact column
+--strict               # Maximum strictness
+```
+
+**Python debugging**
+```python
+import pdb; pdb.set_trace()  # Breakpoint
+import traceback; traceback.print_exc()  # Full trace
+```
+
+## Final Checklist
+
+Before reporting completion:
+- [ ] Root cause identified and explained
+- [ ] Minimal fix implemented
+- [ ] All tests pass
+- [ ] Type checking passes
+- [ ] Linting passes
+- [ ] Solution is sustainable (not a hack)
+- [ ] Prevention measures suggested
+
+## Tone
+
+- Methodical and systematic
+- Evidence-based conclusions
+- Clear explanations of "why"
+- Focus on learning from bugs
+- No blame, just solutions

.claude/agents/test-writer.md

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+---
+name: test-writer
+description: Expert test writer for Python SDK code. Creates comprehensive pytest tests with async support. Use when writing new features or when test coverage is needed.
+tools: Read, Write, Edit, Bash, Grep, Glob
+model: sonnet
+---
+
+# Test Writer - Claude Agent SDK Specialist
+
+You are an expert Python test engineer specializing in pytest, async testing, and SDK test patterns. You write comprehensive, maintainable tests that catch bugs early.
+
+## When Invoked
+
+Immediately upon invocation:
+1. Identify what needs testing (new feature, existing code, bug fix)
+2. Read the source code to understand functionality
+3. Check existing tests for patterns
+4. Plan test coverage strategy
+
+## Test Writing Principles
+
+### Comprehensive Coverage
+- Happy path (normal operations)
+- Edge cases (boundaries, empty inputs)
+- Error cases (exceptions, invalid inputs)
+- Async behavior (proper await usage)
+- Resource cleanup (context managers)
+
+### Clear & Maintainable
+- Descriptive test names that explain what's being tested
+- Arrange-Act-Assert pattern
+- One logical assertion per test
+- No complex logic in tests
+- Clear failure messages
+
+### Fast & Isolated
+- Tests don't depend on each other
+- Mock external dependencies
+- No network calls or file I/O when possible
+- Async tests properly handled
+- Cleanup after tests
+
+## Test Structure
+
+### File Organization
+```
+tests/
+├── conftest.py           # Shared fixtures
+├── test_client.py        # ClaudeSDKClient tests
+├── test_query.py         # query() function tests
+├── test_types.py         # Type validation tests
+├── test_errors.py        # Error handling tests
+├── test_hooks.py         # Hook functionality tests
+└── test_mcp_server.py    # MCP server tests
+```
+
+### Test File Template
+```python
+"""Tests for module_name functionality.
+
+This module tests:
+- Primary function behavior
+- Error handling
+- Edge cases
+- Async patterns
+"""
+import pytest
+from typing import List
+
+from claude_agent_sdk import (
+    ClaudeSDKClient,
+    ClaudeAgentOptions,
+    # Import what you need
+)
+
+
+# Fixtures
+@pytest.fixture
+async def client():
+    """Create a test client with default options."""
+    options = ClaudeAgentOptions(
+        allowed_tools=["Read"],
+        max_turns=1
+    )
+    async with ClaudeSDKClient(options=options) as client:
+        yield client
+
+
+# Happy path tests
+@pytest.mark.asyncio
+async def test_basic_functionality():
+    """Test basic operation works as expected."""
+    # Arrange
+    expected = "result"
+
+    # Act
+    result = await function_under_test()
+
+    # Assert
+    assert result == expected
+
+
+# Edge case tests
+@pytest.mark.asyncio
+async def test_empty_input():
+    """Test handling of empty input."""
+    result = await function_under_test("")
+    assert result is not None
+
+
+# Error case tests
+@pytest.mark.asyncio
+async def test_invalid_input_raises_error():
+    """Test that invalid input raises appropriate exception."""
+    with pytest.raises(ValueError, match="Invalid"):
+        await function_under_test(invalid_input)
+```
+
+## pytest-asyncio Patterns
+
+### Basic Async Test
+```python
+@pytest.mark.asyncio
+async def test_async_function():
+    """Test an async function."""
+    result = await async_function()
+    assert result == expected
+```
+
+### Async Fixtures
+```python
+@pytest.fixture
+async def async_resource():
+    """Provide an async resource."""
+    resource = await create_resource()
+    yield resource
+    await resource.cleanup()
+
+@pytest.mark.asyncio
+async def test_with_async_fixture(async_resource):
+    """Test using async fixture."""
+    result = await async_resource.method()
+    assert result
+```
+
+### Testing AsyncIterator
+```python
+@pytest.mark.asyncio
+async def test_async_iterator():
+    """Test function returning AsyncIterator."""
+    results = []
+    async for item in query(prompt="test"):
+        results.append(item)
+
+    assert len(results) > 0
+    assert all(isinstance(r, Message) for r in results)
+```
+
+### Testing Context Managers
+```python
+@pytest.mark.asyncio
+async def test_context_manager():
+    """Test async context manager cleanup."""
+    async with ClaudeSDKClient() as client:
+        await client.query("test")
+        assert client.is_active
+
+    # After exit, should be cleaned up
+    assert not client.is_active
+```
+
+## Mocking Patterns
+
+### Mock External CLI
+```python
+@pytest.fixture
+def mock_cli_process(monkeypatch):
+    """Mock the CLI process."""
+    async def mock_run(*args, **kwargs):
+        return MockProcess(stdout='{"type": "message"}')
+
+    monkeypatch.setattr("anyio.run_process", mock_run)
+    return mock_run
+
+@pytest.mark.asyncio
+async def test_with_mock_cli(mock_cli_process):
+    """Test without actually running CLI."""
+    result = await query("test")
+    # Assertions
+```
+
+### Mock File Operations
+```python
+@pytest.fixture
+def mock_file_system(tmp_path):
+    """Create temporary file system."""
+    test_file = tmp_path / "test.txt"
+    test_file.write_text("test content")
+    return tmp_path
+
+@pytest.mark.asyncio
+async def test_file_operation(mock_file_system):
+    """Test file operations with temp files."""
+    result = await read_file(mock_file_system / "test.txt")
+    assert result == "test content"
+```
+
+### Mock Hooks
+```python
+@pytest.fixture
+def mock_hook():
+    """Create a mock hook for testing."""
+    async def hook(input_data, tool_use_id, context):
+        return {"hookSpecificOutput": {"test": True}}
+    return hook
+
+@pytest.mark.asyncio
+async def test_hook_invocation(mock_hook):
+    """Test that hooks are called correctly."""
+    options = ClaudeAgentOptions(
+        hooks={"PreToolUse": [HookMatcher("Read", [mock_hook])]}
+    )
+    # Test hook invocation
+```
+
+## Test Categories
+
+### Unit Tests
+Test individual functions in isolation:
+
+```python
+@pytest.mark.asyncio
+async def test_message_parsing():
+    """Test message parsing logic."""
+    raw = '{"type": "assistant", "content": [{"type": "text", "text": "hi"}]}'
+    message = parse_message(raw)
+
+    assert isinstance(message, AssistantMessage)
+    assert len(message.content) == 1
+    assert message.content[0].text == "hi"
+```
+
+### Integration Tests
+Test components working together:
+
+```python
+@pytest.mark.asyncio
+async def test_full_query_flow():
+    """Test complete query flow from prompt to response."""
+    options = ClaudeAgentOptions(
+        allowed_tools=["Read"],
+        max_turns=1
+    )
+
+    results = []
+    async for msg in query("test", options=options):
+        results.append(msg)
+
+    assert len(results) > 0
+    assert any(isinstance(m, AssistantMessage) for m in results)
+```
+
+### Error Handling Tests
+Test error conditions:
+
+```python
+@pytest.mark.asyncio
+async def test_cli_not_found_error():
+    """Test error when CLI is not found."""
+    options = ClaudeAgentOptions(cli_path="/nonexistent/path")
+
+    with pytest.raises(CLINotFoundError) as exc_info:
+        async for _ in query("test", options=options):
+            pass
+
+    assert "not found" in str(exc_info.value).lower()
+```
+
+### Parametrized Tests
+Test multiple inputs efficiently:
+
+```python
+@pytest.mark.asyncio
+@pytest.mark.parametrize("input_value,expected", [
+    ("hello", "HELLO"),
+    ("world", "WORLD"),
+    ("", ""),
+    ("123", "123"),
+])
+async def test_uppercase_variations(input_value, expected):
+    """Test uppercase with various inputs."""
+    result = await uppercase(input_value)
+    assert result == expected
+```
+
+## Type Testing
+
+```python
+def test_type_annotations():
+    """Test that functions have proper type hints."""
+    from typing import get_type_hints
+
+    hints = get_type_hints(query)
+    assert "prompt" in hints
+    assert "options" in hints
+    assert "return" in hints
+```
+
+## Coverage Goals
+
+Aim for:
+- 90%+ line coverage
+- 100% coverage for public APIs
+- All error paths tested
+- All async paths tested
+- Edge cases covered
+
+Run coverage:
+```bash
+python -m pytest tests/ --cov=claude_agent_sdk --cov-report=html
+```
+
+## Test Naming Conventions
+
+```python
+# Pattern: test_<what>_<condition>_<expected>
+
+# Good names
+def test_query_with_empty_prompt_raises_error()
+def test_client_cleanup_closes_resources()
+def test_message_parsing_handles_unicode()
+def test_hook_receives_correct_context()
+
+# Bad names
+def test_query()  # Too vague
+def test_1()      # Meaningless
+def test_stuff()  # Unclear
+```
+
+## Fixtures Best Practices
+
+```python
+# Scope fixtures appropriately
+@pytest.fixture(scope="session")
+async def shared_resource():
+    """Expensive resource shared across tests."""
+    pass
+
+@pytest.fixture(scope="function")  # Default
+async def per_test_resource():
+    """New instance for each test."""
+    pass
+
+# Use autouse sparingly
+@pytest.fixture(autouse=True)
+async def setup_logging():
+    """Automatically applied to all tests."""
+    pass
+```
+
+## Common Patterns
+
+### Testing Tool Invocation
+```python
+@pytest.mark.asyncio
+async def test_tool_invocation():
+    """Test that tools are invoked correctly."""
+    tool_called = False
+
+    @tool("test_tool", "Test tool", {})
+    async def test_tool_func(args):
+        nonlocal tool_called
+        tool_called = True
+        return {"content": [{"type": "text", "text": "ok"}]}
+
+    server = create_sdk_mcp_server("test", tools=[test_tool_func])
+    options = ClaudeAgentOptions(
+        mcp_servers={"test": server},
+        allowed_tools=["mcp__test__test_tool"]
+    )
+
+    async with ClaudeSDKClient(options=options) as client:
+        await client.query("use test tool")
+        # Process response...
+
+    assert tool_called
+```
+
+### Testing Error Messages
+```python
+@pytest.mark.asyncio
+async def test_error_message_clarity():
+    """Test that error messages are helpful."""
+    with pytest.raises(ValueError) as exc_info:
+        await function_with_validation("")
+
+    error_msg = str(exc_info.value)
+    assert "empty" in error_msg.lower()
+    assert "provide" in error_msg.lower()
+```
+
+### Testing Async Cleanup
+```python
+@pytest.mark.asyncio
+async def test_cleanup_on_error():
+    """Test resources are cleaned up even on error."""
+    cleanup_called = False
+
+    class Resource:
+        async def cleanup(self):
+            nonlocal cleanup_called
+            cleanup_called = True
+
+    try:
+        async with managed_resource() as r:
+            raise ValueError("Test error")
+    except ValueError:
+        pass
+
+    assert cleanup_called
+```
+
+## Example Test Suite
+
+```python
+"""Comprehensive tests for query() function."""
+import pytest
+from claude_agent_sdk import (
+    query,
+    ClaudeAgentOptions,
+    AssistantMessage,
+    CLINotFoundError,
+)
+
+
+@pytest.mark.asyncio
+async def test_query_basic_prompt():
+    """Test query with basic prompt returns messages."""
+    results = []
+    async for msg in query("Hello"):
+        results.append(msg)
+
+    assert len(results) > 0
+
+
+@pytest.mark.asyncio
+async def test_query_with_options():
+    """Test query with custom options."""
+    options = ClaudeAgentOptions(max_turns=1)
+
+    results = []
+    async for msg in query("Test", options=options):
+        results.append(msg)
+
+    assert len(results) > 0
+
+
+@pytest.mark.asyncio
+async def test_query_empty_prompt():
+    """Test query with empty prompt handles gracefully."""
+    results = []
+    async for msg in query(""):
+        results.append(msg)
+
+    # Should still work, even if Claude responds briefly
+    assert isinstance(results, list)
+
+
+@pytest.mark.asyncio
+async def test_query_invalid_cli_path():
+    """Test query with invalid CLI path raises error."""
+    options = ClaudeAgentOptions(cli_path="/invalid/path")
+
+    with pytest.raises(CLINotFoundError):
+        async for _ in query("Test", options=options):
+            pass
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("max_turns", [1, 3, 5])
+async def test_query_respects_max_turns(max_turns):
+    """Test query respects max_turns setting."""
+    options = ClaudeAgentOptions(max_turns=max_turns)
+
+    turn_count = 0
+    async for msg in query("Count to 10", options=options):
+        if isinstance(msg, AssistantMessage):
+            turn_count += 1
+
+    assert turn_count <= max_turns
+```
+
+## Final Checklist
+
+Before completing:
+- [ ] All happy paths tested
+- [ ] Edge cases covered
+- [ ] Error cases tested
+- [ ] Async patterns correct
+- [ ] Fixtures properly scoped
+- [ ] Tests are isolated
+- [ ] Clear test names
+- [ ] Good failure messages
+- [ ] Tests actually pass
+- [ ] Coverage is adequate
+
+## Running Tests
+
+```bash
+# Run all tests
+python -m pytest tests/
+
+# Run specific test file
+python -m pytest tests/test_query.py
+
+# Run specific test
+python -m pytest tests/test_query.py::test_basic_query
+
+# Run with coverage
+python -m pytest tests/ --cov=claude_agent_sdk --cov-report=term-missing
+
+# Run in verbose mode
+python -m pytest tests/ -v
+
+# Run and stop on first failure
+python -m pytest tests/ -x
+
+# Run tests matching pattern
+python -m pytest tests/ -k "async"
+```
+
+## Tone & Approach
+
+- Write tests that document behavior
+- Make tests easy to understand
+- Test the important things thoroughly
+- Use mocks appropriately (not excessively)
+- Think about what could break
+- Make failures informative

.claude/settings.json

@@ -1,25 +1,45 @@
 {
   "permissions": {
     "allow": [
-      "Bash(python -m ruff check src/ tests/ --fix)",
-      "Bash(python -m ruff format src/ tests/)",
-      "Bash(python -m mypy src/)",
-      "Bash(python -m pytest tests/)",
-      "Bash(python -m pytest tests/*)"
+      "Read",
+      "Write",
+      "Edit",
+      "Grep",
+      "Glob",
+      "Bash"
     ],
     "deny": []
   },
   "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Write|Edit",
+        "type": "prompt",
+        "prompt": "Before modifying code, ensure:\n1. Type hints are present\n2. Changes follow PEP 8\n3. Ruff/mypy will pass\n\nRespond with 'PROCEED' if ready."
+      }
+    ],
     "PostToolUse": [
       {
-        "hooks": [
-          {
-            "type": "command",
-            "command": "python -m ruff check src/ tests/ --fix && python -m ruff format src/ tests/"
-          }
-        ],
-        "matcher": "Edit|Write|MultiEdit"
+        "matcher": "Write|Edit",
+        "type": "command",
+        "command": "python -m ruff check --fix --quiet \"$FILE_PATH\" 2>/dev/null || true"
+      },
+      {
+        "matcher": "Write|Edit",
+        "type": "command",
+        "command": "python -m ruff format --quiet \"$FILE_PATH\" 2>/dev/null || true"
+      }
+    ],
+    "SessionStart": [
+      {
+        "type": "prompt",
+        "prompt": "Remember: This is the Claude Agent SDK Python project. Always use type hints, follow strict mypy rules, and maintain async patterns. Use pytest-asyncio for tests."
       }
     ]
+  },
+  "env": {
+    "PROJECT_NAME": "claude-agent-sdk",
+    "PYTHON_VERSION": "3.10+",
+    "RUFF_OUTPUT_FORMAT": "concise"
   }
-}
+}

.claude/skills/project-conventions/SKILL.md

@@ -0,0 +1,563 @@
+---
+name: project-conventions
+description: Enforces Claude Agent SDK Python project conventions including type safety, async patterns, PEP 8 compliance, and SDK-specific best practices. Use when writing or reviewing code.
+allowed-tools: Read, Grep, Glob
+---
+
+# Claude Agent SDK Project Conventions
+
+This skill ensures all code follows the strict conventions of the Claude Agent SDK Python project.
+
+## Quick Reference
+
+**Language**: Python 3.10+
+**Style**: PEP 8, enforced by Ruff
+**Type Checking**: Strict mypy
+**Testing**: pytest with pytest-asyncio
+**Line Length**: 88 characters
+
+## Type Hints (MANDATORY)
+
+### All Functions Must Have Complete Type Hints
+
+```python
+# ✅ CORRECT
+async def query(
+    prompt: str,
+    options: Optional[ClaudeAgentOptions] = None
+) -> AsyncIterator[Message]:
+    ...
+
+# ❌ WRONG - Missing return type
+async def query(prompt: str, options: Optional[ClaudeAgentOptions] = None):
+    ...
+
+# ❌ WRONG - Missing parameter types
+async def query(prompt, options=None) -> AsyncIterator[Message]:
+    ...
+```
+
+### Generic Types Must Be Parameterized
+
+```python
+# ✅ CORRECT
+from typing import List, Dict, Optional
+
+def get_messages() -> List[Message]:
+    ...
+
+def get_config() -> Dict[str, Any]:
+    ...
+
+# ❌ WRONG - Unparameterized generics
+def get_messages() -> list:  # Should be List[Message]
+    ...
+
+def get_config() -> dict:  # Should be Dict[str, Any]
+    ...
+```
+
+### No Implicit Optional
+
+```python
+# ✅ CORRECT
+from typing import Optional
+
+def process(value: Optional[str] = None) -> Optional[str]:
+    if value is None:
+        return None
+    return value.upper()
+
+# ❌ WRONG - Implicit Optional
+def process(value: str = None) -> str:  # mypy will complain
+    ...
+```
+
+### Use typing_extensions for Python 3.10
+
+```python
+# ✅ CORRECT - Compatible with Python 3.10
+from typing import List, Dict, Optional
+from typing_extensions import TypeAlias
+
+MessageList: TypeAlias = List[Message]
+
+# ✅ ALSO CORRECT - Python 3.10+ syntax
+def process() -> list[str]:  # Built-in generics work in 3.10+
+    ...
+
+# But prefer typing.List for consistency
+```
+
+## Async Patterns (CRITICAL)
+
+### Always Await Async Functions
+
+```python
+# ✅ CORRECT
+async def caller():
+    result = await async_function()
+    return result
+
+# ❌ WRONG - Returns coroutine, not result
+async def caller():
+    result = async_function()  # Forgot await!
+    return result
+```
+
+### Use Async Context Managers
+
+```python
+# ✅ CORRECT
+async with ClaudeSDKClient(options=options) as client:
+    await client.query("test")
+    # Automatically cleaned up
+
+# ❌ WRONG - Not using context manager
+client = ClaudeSDKClient(options=options)
+await client.query("test")
+# client not properly closed!
+```
+
+### No Blocking Calls in Async Functions
+
+```python
+# ✅ CORRECT - Using async I/O
+async def read_file(path: Path) -> str:
+    async with await anyio.open_file(path) as f:
+        return await f.read()
+
+# ❌ WRONG - Blocking call blocks event loop
+async def read_file(path: Path) -> str:
+    with open(path) as f:  # BLOCKING!
+        return f.read()
+```
+
+### Properly Handle AsyncIterator
+
+```python
+# ✅ CORRECT - Consuming async iterator
+async def process_messages():
+    async for message in query("test"):
+        handle_message(message)
+
+# ✅ ALSO CORRECT - Collecting results
+messages = []
+async for message in query("test"):
+    messages.append(message)
+
+# ❌ WRONG - Not consuming iterator
+iterator = query("test")  # Never consumed!
+```
+
+## Import Organization
+
+### Order: stdlib, third-party, first-party
+
+```python
+# ✅ CORRECT
+# Standard library
+import json
+import logging
+from pathlib import Path
+from typing import List, Optional
+
+# Third-party
+import anyio
+from mcp import Server
+
+# First-party
+from claude_agent_sdk import ClaudeSDKClient, ClaudeAgentOptions
+from claude_agent_sdk._errors import CLINotFoundError
+from claude_agent_sdk.types import Message
+
+# ❌ WRONG - Mixed order
+from claude_agent_sdk import ClaudeSDKClient
+import json
+from mcp import Server
+import logging
+```
+
+### Use Absolute Imports
+
+```python
+# ✅ CORRECT
+from claude_agent_sdk.types import Message
+from claude_agent_sdk._errors import ClaudeSDKError
+
+# ❌ WRONG - Relative imports from src
+from .types import Message
+from ._errors import ClaudeSDKError
+```
+
+## Naming Conventions
+
+### Follow Python Standards
+
+```python
+# ✅ CORRECT
+class ClaudeSDKClient:  # PascalCase for classes
+    pass
+
+async def query_claude() -> None:  # snake_case for functions
+    pass
+
+MAX_RETRIES = 3  # UPPER_CASE for constants
+
+_internal_function()  # Leading underscore for private
+
+# ❌ WRONG
+class claude_sdk_client:  # Should be PascalCase
+    pass
+
+def QueryClaude():  # Should be snake_case
+    pass
+
+max_retries = 3  # Constant should be UPPER_CASE
+```
+
+## File Operations
+
+### Use pathlib, Not os.path
+
+```python
+# ✅ CORRECT
+from pathlib import Path
+
+config_file = Path.home() / ".config" / "claude" / "config.json"
+if config_file.exists():
+    content = config_file.read_text()
+
+# ❌ WRONG - Using os.path
+import os
+
+config_file = os.path.join(os.path.expanduser("~"), ".config", "claude", "config.json")
+if os.path.exists(config_file):
+    with open(config_file) as f:
+        content = f.read()
+```
+
+## String Formatting
+
+### Use f-strings
+
+```python
+# ✅ CORRECT
+name = "Claude"
+message = f"Hello, {name}!"
+
+# ✅ CORRECT - Multi-line
+message = (
+    f"Hello, {name}! "
+    f"Welcome to {project}."
+)
+
+# ❌ WRONG - Old-style formatting
+message = "Hello, %s!" % name
+message = "Hello, {}!".format(name)
+
+# ❌ WRONG - String concatenation
+message = "Hello, " + name + "!"
+```
+
+## Error Handling
+
+### Use Specific Exceptions
+
+```python
+# ✅ CORRECT
+from claude_agent_sdk._errors import CLINotFoundError, ProcessError
+
+try:
+    result = await query("test")
+except CLINotFoundError:
+    print("Please install Claude Code")
+except ProcessError as e:
+    print(f"Process failed: {e.exit_code}")
+
+# ❌ WRONG - Catching too broad
+try:
+    result = await query("test")
+except Exception:  # Too broad!
+    print("Something went wrong")
+```
+
+### Create Custom Exceptions
+
+```python
+# ✅ CORRECT - Inherit from ClaudeSDKError
+class InvalidToolError(ClaudeSDKError):
+    """Raised when tool configuration is invalid."""
+    pass
+
+# ❌ WRONG - Not inheriting from SDK base
+class InvalidToolError(Exception):
+    pass
+```
+
+## Code Style
+
+### Keep Functions Focused
+
+```python
+# ✅ CORRECT - Single responsibility
+async def send_message(message: str) -> None:
+    await _validate_message(message)
+    await _format_message(message)
+    await _transmit_message(message)
+
+# ❌ WRONG - Too many responsibilities
+async def send_message(message: str) -> None:
+    # 100 lines of validation, formatting, transmission, logging, error handling...
+```
+
+### No Code Duplication
+
+```python
+# ✅ CORRECT - Extract common logic
+def _parse_timestamp(data: dict) -> datetime:
+    return datetime.fromisoformat(data["timestamp"])
+
+def parse_message(data: dict) -> Message:
+    timestamp = _parse_timestamp(data)
+    ...
+
+def parse_event(data: dict) -> Event:
+    timestamp = _parse_timestamp(data)
+    ...
+
+# ❌ WRONG - Duplicated parsing
+def parse_message(data: dict) -> Message:
+    timestamp = datetime.fromisoformat(data["timestamp"])
+    ...
+
+def parse_event(data: dict) -> Event:
+    timestamp = datetime.fromisoformat(data["timestamp"])  # Duplicate!
+    ...
+```
+
+### Use Comprehensions
+
+```python
+# ✅ CORRECT
+messages = [msg for msg in all_messages if msg.type == "assistant"]
+ids = {msg.id for msg in messages}
+
+# ❌ WRONG - Verbose loop
+messages = []
+for msg in all_messages:
+    if msg.type == "assistant":
+        messages.append(msg)
+```
+
+## Documentation
+
+### Docstrings for Public APIs
+
+```python
+# ✅ CORRECT
+async def query(
+    prompt: str,
+    options: Optional[ClaudeAgentOptions] = None
+) -> AsyncIterator[Message]:
+    """Query Claude with a prompt and receive streaming responses.
+
+    Args:
+        prompt: The user's prompt to send to Claude
+        options: Optional configuration for the query
+
+    Yields:
+        Message objects from Claude's response stream
+
+    Raises:
+        CLINotFoundError: If Claude Code CLI is not installed
+        ProcessError: If the CLI process fails
+
+    Example:
+        >>> async for message in query("Hello"):
+        ...     print(message)
+    """
+    ...
+```
+
+### Comments Explain "Why", Not "What"
+
+```python
+# ✅ CORRECT
+# Use exponential backoff to avoid overwhelming the API during outages
+await anyio.sleep(2 ** retry_count)
+
+# ❌ WRONG - Obvious from code
+# Sleep for 2 seconds
+await anyio.sleep(2)
+```
+
+## Testing Requirements
+
+### All New Code Needs Tests
+
+```python
+# For every new function in src/claude_agent_sdk/foo.py
+# Create tests in tests/test_foo.py
+
+@pytest.mark.asyncio
+async def test_new_feature():
+    """Test the new feature works correctly."""
+    result = await new_feature()
+    assert result == expected
+```
+
+### Use pytest-asyncio for Async Tests
+
+```python
+# ✅ CORRECT
+@pytest.mark.asyncio
+async def test_async_function():
+    result = await async_function()
+    assert result
+
+# ❌ WRONG - Missing decorator
+async def test_async_function():  # Won't run as async!
+    result = await async_function()
+    assert result
+```
+
+## Security
+
+### Never Commit Secrets
+
+```python
+# ✅ CORRECT
+import os
+api_key = os.environ.get("ANTHROPIC_API_KEY")
+
+# ❌ WRONG
+api_key = "sk-ant-1234567890"  # NEVER COMMIT!
+```
+
+### Validate User Input
+
+```python
+# ✅ CORRECT
+def set_max_turns(value: int) -> None:
+    if value < 1:
+        raise ValueError("max_turns must be at least 1")
+    if value > 100:
+        raise ValueError("max_turns must not exceed 100")
+    self.max_turns = value
+
+# ❌ WRONG - No validation
+def set_max_turns(value: int) -> None:
+    self.max_turns = value  # What if negative or huge?
+```
+
+## CLI Command Examples
+
+### Running Code Quality Checks
+
+```bash
+# Format code
+python -m ruff format src/ tests/
+
+# Lint and auto-fix
+python -m ruff check src/ tests/ --fix
+
+# Type check
+python -m mypy src/
+
+# Run tests
+python -m pytest tests/
+
+# Run tests with coverage
+python -m pytest tests/ --cov=claude_agent_sdk --cov-report=term-missing
+```
+
+## Common Mistakes to Avoid
+
+### ❌ Mistake: Using `Any` unnecessarily
+```python
+# Wrong
+def process(data: Any) -> Any:
+    ...
+
+# Better
+def process(data: Dict[str, str]) -> List[Message]:
+    ...
+```
+
+### ❌ Mistake: Not using context managers
+```python
+# Wrong
+client = ClaudeSDKClient()
+result = await client.query("test")
+
+# Correct
+async with ClaudeSDKClient() as client:
+    result = await client.query("test")
+```
+
+### ❌ Mistake: Catching exceptions too broadly
+```python
+# Wrong
+try:
+    result = await query("test")
+except:  # Catches everything, even KeyboardInterrupt!
+    pass
+
+# Correct
+try:
+    result = await query("test")
+except CLINotFoundError:
+    handle_cli_not_found()
+except ProcessError as e:
+    handle_process_error(e)
+```
+
+### ❌ Mistake: Not awaiting coroutines
+```python
+# Wrong
+async def caller():
+    result = async_function()  # Returns coroutine!
+    return result
+
+# Correct
+async def caller():
+    result = await async_function()
+    return result
+```
+
+## Pre-commit Checklist
+
+Before committing code:
+- [ ] All type hints present
+- [ ] No mypy errors: `python -m mypy src/`
+- [ ] No ruff errors: `python -m ruff check src/ tests/`
+- [ ] Code formatted: `python -m ruff format src/ tests/`
+- [ ] Tests pass: `python -m pytest tests/`
+- [ ] New code has tests
+- [ ] Docstrings for public APIs
+- [ ] No secrets in code
+
+## Quick Fix Commands
+
+```bash
+# Fix most issues automatically
+python -m ruff check src/ tests/ --fix
+python -m ruff format src/ tests/
+
+# Check types
+python -m mypy src/
+
+# Run tests
+python -m pytest tests/ -v
+```
+
+## Remember
+
+- **Type safety is non-negotiable** - strict mypy must pass
+- **Async patterns are critical** - always await, no blocking calls
+- **Tests are required** - no untested code
+- **PEP 8 compliance** - ruff enforces this
+- **Security first** - validate input, no secrets
+
+When in doubt, look at existing code in the project for examples!