Originally published at tengli. dev Your MCP server can be 100% spec-compliant and still be unusable by an agent. The Model Context Protocol spec tells you how to transport tools: JSON-RPC framing, capability negotiation, schema shapes.
Source: [Dev.to](https://dev.to/tengbyte/i-lint-scanned-36-popular-mcp-servers-a-third-of-them-are-failing-your-agent-102d)