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Version change: 1.0.0 → 1.1.0
Modified principles: Enterprise-Grade Security → Essential Security, Performance and Scalability updated
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Removed sections: VS Code MCP Client Integration (out of scope)
Templates requiring updates: ✅ constitution.md
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# OAuth2 MCP Authorization Library Project Constitution

**Version:** 1.1.0  
**Ratified:** 2025-01-27  
**Last Amended:** 2025-01-27

## Preamble

This constitution establishes the fundamental principles and governance framework for the OAuth2 MCP Authorization Library project. These principles guide all development decisions, architectural choices, and community interactions to ensure the project remains focused, secure, and aligned with its core mission of providing minimal, secure, and user-friendly OAuth2 authentication for MCP servers.

## Core Principles

### Minimal API Surface
All public APIs MUST be designed for maximum simplicity and developer productivity. The primary API MUST enable authentication with a single line of code. Complex configuration MUST be optional and hidden behind sensible defaults. The library MUST auto-discover authorization servers and handle token management transparently.

**Rationale:** The core value proposition is eliminating OAuth2 complexity for MCP developers. A complex API defeats the purpose of the library and creates barriers to adoption.

### Essential Security
The library MUST implement OAuth 2.1 security requirements including audience binding, issuer validation, and JWT signature verification. All communications MUST use HTTPS with proper certificate validation. The library MUST provide secure JWT token validation with JWKS caching and fail-fast behavior on JWKS fetch failures. Token storage MUST use in-memory caching only with TTL expiration.

**Rationale:** Security is fundamental to OAuth2 authentication. The library focuses on essential security requirements for MCP server authentication while maintaining simplicity and minimal configuration.

### Developer Experience First
The library MUST provide clear, actionable error messages with specific guidance for resolution. Documentation MUST include working examples for common scenarios. The API MUST be type-safe with comprehensive Pydantic v2 validation. Testing MUST achieve >95% code coverage with integration tests against real OAuth2 servers.

**Rationale:** Developer productivity is the primary success metric. Poor developer experience will lead to low adoption regardless of technical quality.

### Performance and Scalability
Token validation MUST complete in <100ms for JWT validation. JWKS fetching MUST complete in <500ms for initial fetch, cached thereafter. Middleware overhead MUST be <50ms additional latency. The library MUST support 100+ simultaneous requests with efficient connection reuse. Memory usage MUST be <10MB for middleware instances.

**Rationale:** Performance directly impacts user experience and MCP server adoption. Poor performance creates friction and limits scalability in production environments.

## Governance

### Amendment Procedure
Constitutional amendments require approval from the project maintainers and must be documented with clear rationale. All amendments must maintain backward compatibility with existing implementations unless a major version bump is planned and communicated to the community with 6 months notice.

### Versioning Policy
The constitution follows semantic versioning:
- **MAJOR**: Backward incompatible governance/principle removals or redefinitions
- **MINOR**: New principle/section added or materially expanded guidance  
- **PATCH**: Clarifications, wording, typo fixes, non-semantic refinements

### Compliance Review
All project artifacts, including specifications, implementation plans, and task lists, must be reviewed for constitutional compliance before acceptance. Non-compliant proposals must be amended or rejected. Each principle must be explicitly validated against all proposed changes.

### Enforcement
Constitutional compliance is enforced through mandatory review of all pull requests against principle adherence. Automated testing validates performance and security requirements. Community feedback and adoption metrics validate developer experience principles.

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*This constitution serves as the foundational document for all project decisions and must be referenced in all major architectural and implementation choices.*