mcp-builderlisted

# MCP Server Builder ## Activation Boundary Use this skill only for an MCP server authoring or improvement task. Repository classification alone does not activate it or grant network, credential, tool, browser, or external-mutation access. ## Phase 1: Understand and Plan 1. Identify the user workflows the server must support. 2. Read the bundled references before choosing a language or transport. 3. Inventory required upstream documentation. If current external documentation is necessary, stop at the existing network opt-in boundary and record the exact source and immutable revision to inspect. Never rely on a moving branch. 4. List tool, resource, and prompt surfaces with their read/write effects. 5. Define authentication as an injected runtime boundary. Do not request, inspect, persist, or expose credentials while authoring the bundle. ## Phase 2: Implement - Use clear, action-oriented names and precise input schemas. - Return focused structured data and actionable errors. - Mark destructive, idempotent, read-only, and open-world behavior accurately. - Add pagination or filtering when responses can grow without bound. - Keep transport and service clients behind small interfaces that can be tested locally. - Never infer authorization from tool annotations or repository classification. Language-specific patterns are in: - [reference/node_mcp_server.md](reference/node_mcp_server.md) - [reference/python_mcp_server.md](reference/python_mcp_server.md) - [referenc