leonard_acp 0.2.2

ACP (Agent Client Protocol) model provider for Leonard — drives any ACP-compatible coding agent as a per-turn decision oracle behind leonard_agent's ModelProvider seam.

leonard_acp

ACP (Agent Client Protocol) model provider for Leonard. It drives any ACP-compatible coding agent as a per-turn decision oracle behind leonard_agent's ModelProvider seam, so leonard_cli can steer a live app with an external agent instead of a hosted model.

Part of the lenny workspace.

Drive the DevTools panel with GitHub Copilot or Codex

The Leonard DevTools panel can use a coding agent you are already signed in to as its brain. The panel runs in a browser and cannot start processes, so a small bridge on your machine starts the agent and serves it to the panel over the Dart Tooling Daemon (DTD).

1. Install and sign in to the agent:

   • GitHub Copilot CLI: install copilot, run it once and sign in.
   • Codex: needs npx; the bridge runs @agentclientprotocol/codex-acp, signed in with your Codex account.

2. Add the bridge to your app's dev dependencies, next to leonard_flutter:

   dev_dependencies:
     leonard_acp: ^0.2.2
   

3. Run your app and note the DTD address it prints:

   flutter run --print-dtd
   # The Dart Tooling Daemon is available at: ws://127.0.0.1:PORT/SECRET=
   

4. In a second terminal, from the app's directory, start the bridge with that address:

   dart run leonard_acp:dtd_host --dtd-uri 'ws://127.0.0.1:PORT/SECRET=' --dtd-secret x
   

   --dtd-secret must be non-empty; any value works. Add -v to see the agent's own log.

5. Open DevTools from flutter run, go to the leonard tab, then Settings. Choose provider acp, then the harness (copilot or codex-acp) and a model from the list the agent reports. Start a run with a goal.

If the panel shows acp — no ACP host is registered, the bridge is not running against this app's DTD, or it started after the panel opened: the panel looks for the bridge when it loads, so reload the panel. The panel and the bridge must agree on the service name: use leonard_acp 0.2.2 or later with leonard_flutter 0.4.2 or later. The bridge serves one session at a time; starting a new run replaces the previous one.

What the agent does in this mode: it chooses Leonard's next action each turn from a text description of the screen. It does not get screenshots. Leonard grants it no file system and no terminal and refuses every permission request it makes. An agent's own built-in tools that need no permission (for example read-only file tools) are governed by the agent, in the directory the bridge was started from (--cwd).