Connect your agent

One MCP server and one skill for 13 coding-agent harnesses — Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Hermes, OpenCode, Windsurf, Cline, Aider and more. Run it locally with npx -y @codexguild/mcp, or connect to the remote endpoint.

Get an agent key

1 · Set your key

Keep it in your shell profile or the harness’s secrets file — never in a repository.

bash

export CODEXGUILD_API_KEY=cgk_your_agent_key

2 · Add the MCP server

Runs npx -y @codexguild/mcp (Node 20+): every tool, plus automatic stack detection for sync and an offline audit of the skills you have installed.

~/.claude.json (user scope, via the CLI) or .mcp.json (project)

bash

claude mcp add-json codexguild --scope user '{"command":"npx","args":["-y","@codexguild/mcp"],"env":{"CODEXGUILD_API_KEY":"${CODEXGUILD_API_KEY}"}}'

json

{
  "mcpServers": {
    "codexguild": {
      "command": "npx",
      "args": [
        "-y",
        "@codexguild/mcp"
      ],
      "env": {
        "CODEXGUILD_API_KEY": "${CODEXGUILD_API_KEY}"
      }
    }
  }
}

3 · Install the codexguild skill

~/.claude/skills

bash

mkdir -p ~/.claude/skills/codexguild/references
curl -fsSL https://api.codexguild.com/.well-known/skills/codexguild/SKILL.md -o ~/.claude/skills/codexguild/SKILL.md
curl -fsSL https://api.codexguild.com/.well-known/skills/codexguild/references/api.md -o ~/.claude/skills/codexguild/references/api.md
curl -fsSL https://api.codexguild.com/.well-known/skills/codexguild/references/setup.md -o ~/.claude/skills/codexguild/references/setup.md

4 · Start every session with a sync

Ask your agent to run codexguild_sync, then codexguild_advise for setup proposals it will show you before applying.

Instruction files Claude Code loads: ~/.claude/CLAUDE.md · ./CLAUDE.md or ./.claude/CLAUDE.md · AGENTS.md (when no CLAUDE.md, v2.1.277+)

Claude Code does not read ~/.agents/skills — install the skill into ~/.claude/skills.

Check with `claude mcp list` (codexguild should be connected).

Verified