OpenWriterControle/packages/plugin-abilities

@openagents/plugin-abilities

Enforced, validated workflows for OpenCode agents.

Overview

Abilities solve the fundamental problem with Skills: LLMs ignore them. With Abilities:

• Steps must run (enforced via hooks)
• Scripts run deterministically (no AI variance)
• Validation guarantees each step completed
• Multi-agent coordination just works

Installation

As OpenCode Plugin

Add to your opencode.json:

{
  "plugin": [
    "file://./packages/plugin-abilities/src/opencode-plugin.ts"
  ],
  "abilities": {
    "enabled": true,
    "auto_trigger": true,
    "enforcement": "strict"
  }
}

As Standalone Package

bun add @openagents/plugin-abilities

Quick Start

1. Create an ability

# .opencode/abilities/deploy/ability.yaml
name: deploy
description: Deploy with safety checks

triggers:
  keywords:
    - "deploy"
    - "ship it"

inputs:
  version:
    type: string
    required: true
    pattern: '^v\d+\.\d+\.\d+$'

steps:
  - id: test
    type: script
    run: npm test
    validation:
      exit_code: 0

  - id: build
    type: script
    run: npm run build
    needs: [test]

  - id: deploy
    type: script
    run: ./deploy.sh {{inputs.version}}
    needs: [build]

2. Run the ability

/ability run deploy --version=v1.2.3

Or let it auto-detect from natural language:

User: "Deploy v1.2.3 to production"
→ Ability detected: deploy

Step Types

Script

Runs a shell command deterministically.

- id: test
  type: script
  run: npm test
  cwd: ./packages/api
  env:
    NODE_ENV: test
  validation:
    exit_code: 0
    stdout_contains: "passed"
  timeout: 5m
  on_failure: stop

Agent

Calls an OpenAgents Control agent.

- id: review
  type: agent
  agent: reviewer
  prompt: "Review the code changes"
  needs: [test]

Skill

Loads an existing skill.

- id: docs
  type: skill
  skill: generate-docs

Approval

Human approval gate.

- id: approve
  type: approval
  prompt: "Deploy to production?"
  when: inputs.environment == "production"

Workflow

Nested workflow (calls another ability).

- id: setup
  type: workflow
  workflow: setup-environment
  inputs:
    env: {{inputs.environment}}

Input Validation

inputs:
  version:
    type: string
    required: true
    pattern: '^v\d+\.\d+\.\d+$'
  
  count:
    type: number
    min: 1
    max: 100
    default: 10
  
  env:
    type: string
    enum: [dev, staging, prod]

Dependencies

Steps can depend on other steps:

steps:
  - id: test
    type: script
    run: npm test

  - id: build
    needs: [test]  # Runs after test completes
    type: script
    run: npm run build

  - id: deploy
    needs: [build]  # Runs after build completes
    type: script
    run: ./deploy.sh

Conditional Execution

- id: deploy-prod
  type: script
  run: ./deploy.sh prod
  when: inputs.environment == "production"

Enforcement

Abilities enforce execution order via hooks:

• strict: Block ALL tools outside current step (recommended)
• normal: Block destructive tools, warn on others
• loose: Advisory only

settings:
  enforcement: strict

How Enforcement Works

1. tool.execute.before - Blocks tools based on current step type:

   • Script steps: Block ALL tools (script runs deterministically)
   • Agent steps: Allow only agent invocation tools (task, background_task)
   • Approval steps: Block until user approves
   • Skill steps: Allow only skill-loading tools

2. chat.message - Injects ability context into every message:

   • Shows current ability name and progress
   • Shows current step instructions
   • Reminds AI what to do next

3. session.idle - Prevents session exit while ability running:

   • Injects continuation message
   • In strict mode, blocks exit until complete

Always Allowed Tools

These tools are never blocked (read-only/status):

ability.list, ability.status, ability.cancel,
todoread, read, glob, grep,
lsp_hover, lsp_diagnostics, lsp_document_symbols

Agent Attachment

Abilities can be attached to specific agents:

In Ability Definition

# Restrict to specific agents
compatible_agents:
  - deploy-agent
  - devops-agent

# Or exclusive to one agent
exclusive_agent: deploy-agent

Via Agent Frontmatter

---
name: deploy-agent
abilities:
  - deploy/production
  - deploy/staging
  - rollback
---

Checking Agent Abilities

Use the ability.agent tool:

ability.agent({ agent: "deploy-agent" })
→ Lists all abilities available to that agent

API

Tools

• ability.list - List available abilities
• ability.validate <name> - Validate an ability
• ability.run <name> [inputs] - Execute an ability
• ability.status - Get active execution status

Programmatic (SDK)

import { createAbilitiesSDK } from '@openagents/plugin-abilities/sdk'

// Create SDK instance
const sdk = createAbilitiesSDK({
  projectDir: '.opencode/abilities',
  includeGlobal: true
})

// List all abilities
const abilities = await sdk.list()
// => [{ name, description, source, triggers, inputCount, stepCount }]

// Get specific ability
const ability = await sdk.get('deploy')

// Validate
const { valid, errors } = await sdk.validate('deploy')

// Execute with inputs
const result = await sdk.execute('deploy', { version: 'v1.2.3' })
// => { id, status, ability, duration, steps, formatted }

// Check status
const status = await sdk.status()
// => { active, ability, currentStep, progress, status }

// Cancel active execution
await sdk.cancel()

// Wait for completion (async)
const final = await sdk.waitFor(result.id, 60000)

// Cleanup when done
sdk.cleanup()

Low-level API

import { loadAbilities, executeAbility, validateAbility } from '@openagents/plugin-abilities'

// Load all abilities
const abilities = await loadAbilities({
  projectDir: '.opencode/abilities',
})

// Validate
const result = validateAbility(ability)

// Execute
const execution = await executeAbility(ability, inputs, context)

File Structure

.opencode/
└── abilities/
    ├── deploy/
    │   └── ability.yaml
    ├── test-suite/
    │   └── ability.yaml
    └── simple.yaml

Development

Running Tests

cd packages/plugin-abilities
bun test

Test Results: 87 tests passing across 7 test files

Test Coverage

• executor.test.ts - Script execution, step ordering, validation
• validator.test.ts - Ability validation, input validation
• enforcement.test.ts - Hook enforcement, agent attachment
• integration.test.ts - Full lifecycle, ExecutionManager, error handling
• trigger.test.ts - Keyword/pattern matching, auto-detection

Building

bun run build

Testing Plugin Locally

bun test-plugin.ts

Implementation Status

• Phase 1: Foundation (loader, validator, script executor)
• Phase 2: Agent Integration (agent/skill/approval steps, triggers)
• Phase 3: Enforcement (hooks, agent attachment, execution state)
• Phase 4: Polish (context passing, nested workflows, SDK)

All phases complete! 87 tests passing.

License

MIT