opencode-advisor

Advisor tool plugin for OpenCode.

Adds an explicit advisor tool that consults a stronger model in a temporary forked session and returns concise strategic guidance.

This is an advisor-pattern approximation, not Claude's native server-side advisor API.

Install

npm install opencode-advisor

Add to ~/.config/opencode/opencode.jsonc (or your project's .opencode/opencode.jsonc):

{
  "plugin": ["opencode-advisor@latest"]
}

Quick start

1. Install the plugin.
2. Create either ~/.config/opencode/plugins/advisor-config.json for a global default or .opencode/plugins/advisor-config.json inside a project for a local override.
3. Set advisorModel to the stronger model you want to consult.
4. Start opencode normally — the plugin will inject guidance telling the model to call advisor only when genuinely blocked.

Typical usage

The model will usually call the tool with inputs like:

{
  "question": "What boundary should own validation in this refactor?",
  "blocker": "Parser and repository still depend on each other, so I cannot split the module safely.",
  "attempted": "I first extracted helper functions and then tried interface-based decoupling, but both versions still leave a circular dependency.",
  "context": "Current module mixes parsing, validation, and persistence. I already found circular dependencies between parser.ts and repository.ts."
}

How it works

The plugin registers a custom advisor tool.

When the model calls advisor, the plugin:

1. forks the current session at the current message,
2. sends a focused prompt to a stronger model,
3. returns the advisor's text back as a tool result,
4. deletes the temporary advisor session.

This gives you a practical advisor workflow inside opencode without patching core internals.

parent session
  └─ advisor tool call
      ├─ fork current session
      ├─ prompt stronger model
      ├─ collect text response
      └─ delete temporary advisor session

Configuration

You can place advisor-config.json in either of these locations:

• Global: ~/.config/opencode/plugins/advisor-config.json
• Project-local: .opencode/plugins/advisor-config.json

Precedence is:

1. Environment variables
2. Project-local config
3. Global config
4. Built-in defaults

Example:

{
  "advisorModel": "anthropic/claude-opus-4-5",
  "advisorSystem": null,
  "maxAdvisorCalls": 1,
  "debug": false
}

Fields

Field	Type	Description
advisorModel	string | null	Model to use in provider/model format. If null, the forked session uses its default model.
advisorSystem	string | null	Optional custom system prompt for the advisor session.
maxAdvisorCalls	number	Per-session call budget. Defaults to 1. 0 means unlimited.
debug	boolean	Print initialization and advisor call logs.

Example model setups

{ "advisorModel": "anthropic/claude-opus-4-5" }

{ "advisorModel": "github-copilot/claude-opus-4.6" }

{ "advisorModel": "openai/o3" }

Environment variables

Variable	Values	Description
ADVISOR_MODEL	provider/model	Override advisorModel
ADVISOR_SYSTEM	string	Override advisorSystem
ADVISOR_MAX_CALLS	integer	Override per-session advisor call budget
ADVISOR_DEBUG	true	Enable debug logging

Usage notes

• The plugin injects a system prompt telling the model when to call advisor.
• advisor is intended for genuine blockers after the model has already tried at least one concrete approach.
• Calls should include the decision to make, the blocker, and what has already been attempted.
• No custom agent files are required for this plugin.
• The per-session advisor call budget is cleared automatically when the session is deleted.
• This plugin does not provide Claude-native advisor_tool_result, single-request sub-inference, or native advisor billing semantics.

Limitations

• Each advisor call is an extra session round-trip.
• The advisor runs in a forked opencode session, not inside the provider's native server-side tool loop.
• Native Claude advisor API behavior is out of scope without opencode core/provider support.

Development

Run tests with:

bun test

Packaging note

This package is intended for the opencode/Bun plugin loader. The published entrypoint intentionally points to index.ts rather than a separate transpiled CommonJS build.

License

MIT