skill tool. Where a custom tool is a single executable action, a skill is a scripted workflow the agent can follow step-by-step: gather these files, run these commands, decide what to do next based on the output.
Use skills when:
- You have a workflow you keep re-explaining in prompts (“first run the linter, then …”).
- You want the agent to follow a specific decision tree.
- You want the same workflow available to every session and every agent in the project.
Where they live
Skills are files under.opencode/skill/ (or .opencode/skills/) in the project root. Each file describes the trigger name, when the agent should use it, and the steps involved. The skill tool exposes them to the model.
Related
- Custom Tools — lower-level, single-action extension.
- Custom Agents — bake instructions into an agent instead.