Imported from grikomsn/opencode-copilot-chat (AGENTS.md). Install upstream with npx skills add grikomsn/opencode-copilot-chat. Copyright stays with the author.

Repository guide

Project shape

This is a small, strict-TypeScript VS Code extension that exposes OpenCode Zen, OpenCode Go, and OpenCode Console as native Copilot Chat language-model providers. It targets Node.js 22+ and VS Code 1.125+.

• src/extension.ts: activation and dependency wiring
• src/commands/: sign-in, management, diagnostics, connection, and model commands
• src/provider.ts: language-model provider facade, model discovery, request lifecycle, and usage capture
• src/provider/: message conversion, request construction, and VS Code response projection
• src/auth/: API-key and Console device-code authentication; credentials live in VS Code SecretStorage
• src/models/: model catalog and model-specific reasoning configuration
• src/models/metadata.ts: shared persisted models.dev enrichment for Zen and Go discovery
• src/transport/: OpenCode request identity plus Chat Completions, Messages, Responses, Google, and SSE dialects
• src/tools/: caller-executed VS Code function declarations
• src/usage/: token usage parsing and display helpers
• src/vscode/: proposed VS Code API type augmentations
• Tests are colocated as src/**/*.test.ts using node:test and node:assert/strict
• package.json: extension manifest, public commands/settings, and scripts

Working conventions

• Match the existing style: 2-space indentation, double quotes, semicolons, trailing commas, and explicit types at module/API boundaries.
• Keep changes focused. Prefer pure helpers for parsing, conversion, and formatting so behavior is easy to test without a VS Code host.
• Add or update colocated tests whenever behavior changes. Cover fragmented streams, malformed external data, cancellation, retries, and fallback paths where relevant.
• Keep package.json, README/setup documentation, and command/configuration handling synchronized when public commands, settings, requirements, or workflows change.
• Treat authentication and provider changes as security-sensitive: never log prompts or tokens, never persist credentials outside SecretStorage, and keep Console account synchronization defensive.
• Preserve cancellation and streaming behavior. Do not buffer a response that can be handled incrementally, and retain the single forced token refresh/retry on HTTP 401.
• Do not commit generated out/, source maps, node_modules/, or .vsix files.

Validation

Use the repository scripts rather than ad hoc build commands:

npm ci          # clean dependency install
npm test        # clean compile, then all node:test suites
npm run package # full validation plus VSIX packaging

Run npm test for code changes. Also run npm run package when changing the manifest, packaging rules, dependencies, or release-facing content. The CI matrix uses Node 22, 24, and 26.

Release hygiene

• Add a Changeset with npm run changeset for user-visible behavior changes.
• Documentation-only, test-only, and repository-maintenance changes do not need a Changeset.
• Do not manually bump the version or edit release output unless explicitly performing the release workflow.