OPAL Agent & Skill Assembler

Dual-purpose skill for working with OPAL (OpenLink AI Layer) agents, skills, and function tools. Assemble new agent/skill configurations or exercise existing ones against any OPAL endpoint.

What OPAL Provides

OPAL exposes /chat/api on any OPAL-enabled Virtuoso instance. An Agent orchestrates one or more Skills; a Skill bundles one or more Tools (functions). See references/opal-service-surface.md for the full API surface.

Elicitation Flow

1. OPAL Endpoint

Present these options and ask the user to choose or enter a custom host:

All endpoints are constructed as https://{host}/chat/api, https://{host}/listAgents, etc.

2. Authentication

Ask the user to choose:

• OAuth 2.1: Run Authorization Code flow (see preferences.ttl howto for OAuth flow). Use dynamic client registration at https://{host}/OAuth2/register, capture code on localhost:12345/callback, exchange for Bearer token.
• API Key: Prompt user to paste their Bearer token directly.

3. Mode

Ask the user to choose:

4A. Assemble Mode Details

Agent Assembly:

1. GET https://{host}/listSkills — fetch available skills
2. Present skills as a multi-select list with their descriptions
3. Ask for: agent ID, title, version, optional model key override
4. Generate AGENTS.md using prompts/agents-md-template.md
5. Generate companion .json per references/opal-agent-skill-json-schema.md
6. Offer to upload both to https://{host}/DAV/VAD/personal_assistant/json/{agent_id}.json and .../md/{agent_id}.md
7. Provide curl commands for the upload

Skill Assembly:

1. GET https://{host}/listFunctions — fetch available function tools
2. Present tools as a multi-select list with descriptions
3. Ask for: skill ID, title, version
4. Generate SKILLS.md using prompts/skills-md-template.md
5. Generate companion .json
6. Offer to upload to WebDAV

4B. Exercise Mode Details

Exercise Agent:

1. GET https://{host}/listAgents — fetch available agents
2. Present as single-select list
3. Ask for optional model API key override and test prompt text (default: "Introduce yourself and your capabilities.")
4. Instantiate: POST https://{host}/chat/api with {"agent": "{selected_id}"} and the test message
5. Display the response

Exercise Skill:

1. GET https://{host}/listSkills — fetch available skills
2. Same flow as agent exercise but with {"skills": ["{selected_id}"]}

OAuth Flow Reference

Per preferences.ttl howto (uriburner-oauth-authcode-flow.ttl):

# 1. Register client
curl -X POST https://{host}/OAuth2/register \
  -H "Content-Type: application/json" \
  -d '{"client_name":"OPAL Assembler","redirect_uris":["http://localhost:12345/callback"],"grant_types":["authorization_code"],"token_endpoint_auth_method":"none"}'

# 2. Authorize (open browser)
open "https://{host}/OAuth2/authorize?response_type=code&client_id={client_id}&redirect_uri=http://localhost:12345/callback&scope=openid"

# 3. Exchange code for token
curl -X POST https://{host}/OAuth2/token \
  -d "grant_type=authorization_code&code={code}&redirect_uri=http://localhost:12345/callback&client_id={client_id}&client_secret={client_secret}"

WebDAV Upload

# Upload AGENTS.md / SKILLS.md
curl -X PUT https://{host}/DAV/VAD/personal_assistant/md/{id}.md \
  -H "Authorization: Bearer {token}" \
  -H "Content-Type: text/markdown" \
  --data-binary @{local_file}

# Upload JSON companion
curl -X PUT https://{host}/DAV/VAD/personal_assistant/json/{id}.json \
  -H "Authorization: Bearer {token}" \
  -H "Content-Type: application/json" \
  --data-binary @{local_file}

Verification

After assembly or exercise:

• Assemble: confirm both .md and .json exist at the WebDAV paths
• Assemble: GET https://{host}/listAgents (or /listSkills) should include the newly created agent/skill
• Exercise: confirm the instantiated session returns a meaningful response

References

• references/opal-service-surface.md — full OPAL API surface
• references/opal-agent-skill-json-schema.md — JSON registration format
• OPAL Playground: https://linkeddata.uriburner.com/chat/api
• OAuth howto: preferences.ttl → howto/uriburner-oauth-authcode-flow.ttl

License

AGPL-3.0