MCP Configs

Use MCP config to expose approved external tools and context to coding agents. Treat every MCP server as a capability expansion, not just a convenience toggle.

Core Team Policy

  • approve read-only servers first
  • store secrets outside repository config when possible
  • document a human owner for each server
  • define whether OAuth-based servers are allowed
  • review rate limits, side effects, and data access before rollout

Officially Documented Config Locations

OpenAI Codex

Official docs say Codex stores MCP configuration in:

  • ~/.codex/config.toml
  • .codex/config.toml

The docs also confirm CLI management commands such as:

  • codex mcp add
  • codex mcp list
  • codex mcp login

Claude Code

Anthropic's settings docs list MCP server configuration at:

  • ~/.claude.json
  • .mcp.json

Project settings and personal settings are separate, and Windows ~/.claude paths resolve under %USERPROFILE%\\.claude.

Cline

Official Cline docs confirm MCP config at:

  • ~/.cline/mcp.json

Project-level .cline/mcp.json is also documented in the CLI reference.

Example Approval Checklist

Before approving a server, answer:

  1. what data can this server read?
  2. what actions can it take?
  3. does it mutate production or external systems?
  4. where are credentials stored?
  5. who owns break/fix support?
  6. is the server safe enough for default enablement?

Practical Server Categories

Safer early candidates:

  • docs lookup
  • issue tracker read access
  • read-only filesystem helpers

Higher-risk candidates:

  • database write access
  • deployment systems
  • ticket automation
  • cloud resource creation

Cross-Tool Recommendation

Do not try to keep every tool's MCP config identical if the products use different formats. Instead standardize:

  • approved server list
  • approved auth method
  • approved scopes
  • naming convention
  • owner and rotation policy

Then translate that policy into each tool's config format.

Sources