| name | opendia-harness |
| description | Install, configure, and troubleshoot OpenDia for Grok Build (and other MCP harnesses). Use when setting up the plugin, config.toml MCP entry, ports, extension disconnects, tool timeouts, or tunnel mode.
|
OpenDia harness setup (Grok Build)
Install plugin
grok plugin marketplace add aeonfun/opendia
grok plugin install opendia --trust
Or pin a path:
grok plugin install aeonfun/opendia#plugins/opendia --trust
Enable the plugin (/plugins or [plugins].enabled). Trust is required for the MCP server to attach.
Manual config.toml
[mcp_servers.opendia]
command = "npx"
args = ["-y", "opendia"]
enabled = true
startup_timeout_sec = 60
Optional custom ports (must match what the extension expects):
npx opendia --ws-port=5555 --http-port=5556
Default: WebSocket 5555 (extension), HTTP/SSE 5556, stdio for the AI client.
Extension checklist
- Install from GitHub Releases (Chrome zip or Firefox zip).
- Load unpacked / temporary add-on as documented in the main README.
- Open the extension popup — must show Connected to
ws://localhost:5555 (or your chosen WS port).
- If disconnected: start or restart
npx opendia, then reload the extension.
Doctor commands (Grok Build)
grok mcp list
grok mcp doctor opendia
grok plugin details opendia
Common failures
| Symptom | Likely cause | Fix |
|---|
| MCP tools timeout | Extension not connected | Connect extension; confirm WS port |
| Tools present but actions no-op | Stale socket / server restart | Restart npx opendia, reload extension |
| Cold schemas only | Extension not registered yet | Wait for connect + tools/list_changed, re-list |
| Port conflict | Another process on 5555/5556 | npx opendia --port=6000 and point extension at new WS |
npx slow / fails startup | Cold npm download | Raise startup_timeout_sec; ensure network for first install |
| Tunnel 401 | Missing bearer token | Pass Authorization: Bearer <token> (printed at startup) |
Modes
- Local (default) — stdio + loopback WS/SSE. Correct for Grok Build, Claude Code, Cursor.
--tunnel — ngrok public URL for ChatGPT-style remote connectors. Requires token. Not the default for local harnesses.--http-host=0.0.0.0 — LAN bind; also requires token. Avoid unless intentional.
When not to use OpenDia
- Need fully isolated / headless CI browser → use a cloud or CDP-based MCP instead.
- User has not installed the extension → guide install; do not pretend browser control works.
Related skill
opendia — runtime playbook for page analyze → act → verify once the harness is healthy.
