@gramatr/opencode-plugin

grāmatr lifecycle plugin for OpenCode. Maps OpenCode's plugin events (session.created, message.updated, tool.execute.before, session.idle, session.compacted) to grāmatr hooks — pre-classifying every prompt through the remote MCP server at api.gramatr.com/mcp, restoring session continuity on start, and enforcing git-gate hard rules before destructive shell commands run. Same intelligent context engineering layer used across Claude Code, ChatGPT, Cursor, Codex, and Gemini.

What you get

• Cheaper, faster prompts. A multi-head classification pipeline pre-routes each request and replaces the tens-of-thousands-token system prompt you'd otherwise hand-maintain. The effect compounds the longer you work.
• Consistent behavior across sessions. The same contract — directives plus quality gates — runs on every prompt, so your AI acts the same on session 200 as on session 1.
• Continuity across tools. A session you start in OpenCode resumes cleanly in Claude Code, Cursor, or the web — the handoff is persisted by the same backend.
• Auditable safety rails. Per-prompt hard gates (e.g. git push --force to main is blocked locally before the tool runs).

Install

Add both entries to your opencode.json:

{
  "mcp": {
    "gramatr": {
      "type": "remote",
      "url": "https://api.gramatr.com/mcp",
      "enabled": true
    }
  },
  "plugin": [
    "@gramatr/opencode-plugin"
  ]
}

OpenCode will fetch the package from npm on next start. No global install required.

Authentication

The remote MCP connector authenticates via OAuth 2.0 Device Authorization Grant (RFC 8628). On first connect, OpenCode prompts you to visit a short URL and paste a user code — the same flow used in SSH, WSL, and CI environments where a browser redirect can't reach the client. Tokens are stored by OpenCode's MCP client; the plugin never handles raw credentials.

If you don't have a grāmatr account yet, sign up at gramatr.com.

How it works

OpenCode
   │
   ├── plugin: @gramatr/opencode-plugin  ──┐
   │                                       │ lifecycle events
   │                                       │ (session.created, message.updated, …)
   │                                       ▼
   └── mcp.gramatr (remote, OAuth) ──► api.gramatr.com/mcp
                                       (route_request, load_handoff,
                                        save_reflection, …)

The plugin is a thin connector: every grāmatr hook is invoked against the already-connected remote MCP server declared in the mcp block — there is no local binary, no execSync, no shell-out. Guidance from the server is injected into the active session as a noReply system message so the model sees it before formulating its next response.

When OpenCode's plugin API exposes a typed client.callTool(), the connector will switch to direct MCP tool invocation and drop the prompt-injection path.

Requirements

• OpenCode with @opencode-ai/plugin ≥ 1.0.0
• Node.js ≥ 22
• Network access to https://api.gramatr.com/mcp

Links

• Docs: gramatr.com/docs
• OpenCode plugin reference: opencode.ai/docs/plugins
• Source manifest: contracts/mcp/opencode-plugin-manifest.yaml
• Privacy: gramatr.com/privacy
• Terms: gramatr.com/terms
• Support: [email protected]

License

See LICENSE in this package.