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other Mar 24, 2026

Agent Skills

Define reusable behavior via SKILL.md definitions

by OpenCode opencode.ai 511 words
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Define reusable behavior via SKILL.md definitions

Agent skills let OpenCode discover reusable instructions from your repo or home directory. Skills are loaded on-demand via the native skill tool—agents see available skills and can load the full content when needed.


Place files

Create one folder per skill name and put a SKILL.md inside it. OpenCode searches these locations:


Understand discovery

For project-local paths, OpenCode walks up from your current working directory until it reaches the git worktree. It loads any matching skills/*/SKILL.md in .opencode/ and any matching .claude/skills/*/SKILL.md or .agents/skills/*/SKILL.md along the way.

Global definitions are also loaded from ~/.config/opencode/skills/*/SKILL.md, ~/.claude/skills/*/SKILL.md, and ~/.agents/skills/*/SKILL.md.


Each SKILL.md must start with YAML frontmatter. Only these fields are recognized:

Unknown frontmatter fields are ignored.


Validate names

name must:

Equivalent regex:

^[a-z0-9]+(-[a-z0-9]+)*$

Follow length rules

description must be 1-1024 characters. Keep it specific enough for the agent to choose correctly.


Use an example

Create .opencode/skills/git-release/SKILL.md like this:

---
name: git-release
description: Create consistent releases and changelogs
license: MIT
compatibility: opencode
metadata:
  audience: maintainers
  workflow: github
---

## What I do

- Draft release notes from merged PRs
- Propose a version bump
- Provide a copy-pasteable \`gh release create\` command

## When to use me

Use this when you are preparing a tagged release.
Ask clarifying questions if the target versioning scheme is unclear.

Recognize tool description

OpenCode lists available skills in the skill tool description. Each entry includes the skill name and description:

<available_skills>
  <skill>
    <name>git-release</name>
    <description>Create consistent releases and changelogs</description>
  </skill>
</available_skills>

The agent loads a skill by calling the tool:

skill({ name: "git-release" })

Configure permissions

Control which skills agents can access using pattern-based permissions in opencode.json:

{
  "permission": {
    "skill": {
      "*": "allow",
      "pr-review": "allow",
      "internal-*": "deny",
      "experimental-*": "ask"
    }
  }
}
PermissionBehavior
allowSkill loads immediately
denySkill hidden from agent, access rejected
askUser prompted for approval before loading

Patterns support wildcards: internal-* matches internal-docs, internal-tools, etc.


Override per agent

Give specific agents different permissions than the global defaults.

For custom agents (in agent frontmatter):

---
permission:
  skill:
    "documents-*": "allow"
---

For built-in agents (in opencode.json):

{
  "agent": {
    "plan": {
      "permission": {
        "skill": {
          "internal-*": "allow"
        }
      }
    }
  }
}

Disable the skill tool

Completely disable skills for agents that shouldn’t use them:

For custom agents:

---
tools:
  skill: false
---

For built-in agents:

{
  "agent": {
    "plan": {
      "tools": {
        "skill": false
      }
    }
  }
}

When disabled, the <available_skills> section is omitted entirely.


If a skill does not show up:

  1. Verify SKILL.md is spelled in all caps
  2. Check that frontmatter includes name and description
  3. Ensure skill names are unique across all locations
  4. Check permissions—skills with deny are hidden from agents