OpenCode GO for Nimbalyst

Standalone OpenCode GO agent-provider extension for Nimbalyst 0.71.3 and newer. It does not patch, import, or register itself through Nimbalyst core.

The repository itself is the installable extension: manifest.json and the prebuilt dist/ bundles live at its root. Nimbalyst does not need to run npm or execute build scripts when installing it.

What it provides

• all models published by https://opencode.ai/zen/go/v1/models at release time;
• a separate OpenCode GO provider in Nimbalyst;
• an explicit OpenCode GO API-key field;
• safe synchronization of only the opencode-go entry in OpenCode auth.json;
• an OpenCode CLI auto-update control;
• the official OpenCode CLI/server agent runtime with streaming and attachments.

The extension never reads provider keys from environment variables. The GO key must be entered explicitly in Nimbalyst settings.

Requirements

• Nimbalyst 0.71.3 or newer;
• the official OpenCode CLI available as opencode;
• an active paid OpenCode GO subscription and API key.

Install or update the CLI if necessary:

npm install --global opencode-ai

Install

Nimbalyst's custom-repository installer clones the default branch and requires manifest.json plus a committed dist/ directory. This repository ships both.

In Nimbalyst 0.71.3 the marketplace field is explicitly limited to github.com repository URLs. The canonical Gitsheep repository therefore needs a GitHub mirror before it can be pasted directly into Settings > Marketplace > Install from GitHub. A Gitsheep checkout can still be built and installed locally through Nimbalyst's extension developer tools.

Development

npm install
npm run verify

npm run catalog:check compares the packaged manifest with the live GO endpoint. Because Nimbalyst 0.71.3 does not yet consume dynamic model discovery from an extension backend, a catalog change is shipped as an extension update.

Runtime behavior

The privileged backend starts only after Nimbalyst receives the user's native code consent. Before every session it reads the explicitly stored provider key, updates only OpenCode's opencode-go credential, then launches opencode serve on localhost.

The first launch can take longer when endpoint security software scans the OpenCode or Nimbalyst executable. The startup deadline is 45 seconds.

The CLI update preference is always available in the OpenCode GO provider panel. If the lazy backend is not running yet, the extension stores the non-secret preference in its own namespaced provider slot and applies it on the first GO session. A newer external change to OpenCode's config wins, so the extension does not repeatedly fight another OpenCode integration.

Isolation contract

• Extension id: com.darksheep.opencode-go
• Nimbalyst provider id: opencode-go-agent
• OpenCode provider id: opencode-go
• Backend module id: opencode-go-runtime
• Nimbalyst database access: none
• Nimbalyst workspace-file access: none
• API-key source: the explicit Nimbalyst provider-key field only

The only shared OpenCode setting is the CLI's global autoupdate preference. The extension applies it conservatively and does not overwrite a newer change made by another OpenCode integration.