IAF Agent Bridge

What IAF Agent Bridge MCP server does

IAF Agent Bridge MCP server connects an MCP supervisor to the local Cursor Agent CLI. The supervisor may be Codex, Claude Code, or another stdio-compatible MCP host. Cursor Agent is the executor: it receives the prompt, works in the selected repository, and returns its response through the bridge.

The bridge is designed for work that may require several turns. An initial delegate call returns a session ID, and later calls can provide that ID to continue the same Cursor conversation. This lets a supervisor decide whether to continue, mark the task complete, or report a genuine blocker.

How it works

Communication uses two local stdio links. The MCP host talks to IAF Agent Bridge over MCP, while the bridge talks to Cursor Agent over ACP. A delegate call does not return merely because Cursor has produced a progress message; it waits for the Cursor turn to finish, including internal tools, sub-agents, or follow-up work.

The bridge passes the prompt, session information, and Cursor's result between the two processes. It does not replace the supervisor's decision-making loop. If requested work remains, the supervisor can call delegate again with the returned session ID and a prompt describing what is still missing.

Setup and configuration

Run the bridge with Node.js 20 or later. Install the Cursor CLI as agent, make sure it is available on PATH, and complete authentication with agent login. The published package can be started through npx -y iaf-agent-bridge@1.1.0. A source checkout can instead be built with npm run build and started with node dist/cli.js.

Before connecting an MCP host, run node dist/cli.js doctor from a source checkout, or use the equivalent installed command. The diagnostic checks Node.js, the bridge, the Cursor executable, and authentication. It reports whether authentication is present without printing the account.

The server uses the repository and workspace available to Cursor Agent. No OpenAI API key is needed for the local stdio server. A separate Private mode can be configured for ChatGPT through a Secure MCP Tunnel and restricted runtime key, but that mode requires additional workspace support for MCP write tools and is not hosted by IAF.

Tools and capabilities

IAF Agent Bridge MCP server exposes three tools:

• delegate sends a prompt to Cursor Agent. Include sessionId to resume an existing Cursor conversation.
• cancel stops an in-progress turn. The associated session remains available for later continuation.
• doctor checks the local runtime, bridge, Cursor CLI, and authentication state.

The bridge can be used for ordinary development without approving every individual Cursor tool call. It also supports repositories with a Master Prompt when the expected project files are present; repositories without one continue to work normally.

Limitations and notes

Cursor Agent is the only production executor. Codex and Claude Code act as supervisors, not as the implementation engine. Do not configure the bridge inside Cursor for a repository that Cursor is already editing; the resulting Cursor-to-Cursor delegation loop is refused.

Cursor may edit the named workspace and run commands there. Default protections reject force-pushes, history rewrites, destructive SQL, deletes outside the project, and secret staging. Setting IAF_PERMISSION_MODE=allow-all explicitly changes that behavior, so workspace access and security documentation should be reviewed before use.

The bridge is local and communicates with the local Cursor CLI. The standard OpenAI plugin directory is therefore not applicable, because it reviews hosted HTTPS MCP endpoints. The Cursor Marketplace listing was pending review in the supplied material, although direct installation and the npm package were available.