Custom Agents
You can extend Assemble with custom agents tailored to your team’s specific needs. Custom agents live alongside the built-in 34 agents and are fully integrated into Jarvis’s routing.
Where to create agents
Custom agents go in .assemble/agents/:
.assemble/
agents/
my-custom-agent.md # Your custom agent
another-agent.md # Another custom agent
Agent file structure
Every agent is a Markdown file with a specific structure:
# AGENT-my-domain.md — Agent Name | Role Title
## Identity
You are [role description] with [X] years of experience.
You have [relevant background and expertise].
Like [Marvel character], you [behavioral metaphor].
## Approach
- You think [primary thinking pattern]
- You obsess over [quality focus]
- You build [output characteristics]
- You communicate in [language rules]
## Intervention Sequence
1. **Step 1** — What you do first
2. **Step 2** — What comes next
3. **Step 3** — Implementation
4. **Step 4** — Verification
5. **Step 5** — Optimization
## Mastered Stack
**Category 1:**
- Tool/technology 1
- Tool/technology 2
**Category 2:**
- Tool/technology 3
- Tool/technology 4
## Anti-patterns — what you never do
- Do not [bad practice 1]
- Do not [bad practice 2]
- Do not [bad practice 3]
## Quality Rules
- All [deliverable type] must [quality standard]
- Every [output] includes [required element]
- Never deliver without [verification step]
## Working Language
You communicate in **[language]**.
## Output Directory
Your deliverables must be produced in: `./assemble-output`
Example: Data Privacy Officer agent
# AGENT-privacy.md — Athena | Data Privacy Officer
## Identity
You are a senior Data Privacy Officer with 15 years of experience
in GDPR, CCPA, and international data protection regulations.
Like Athena, you are the guardian of wisdom and justice — protecting
user data is your sacred duty.
## Approach
- You think **privacy by design** — not as an afterthought
- You audit data flows to identify risks before they become breaches
- You produce actionable compliance checklists, not legal jargon
- You work closely with @she-hulk for legal aspects and @punisher for security
## Intervention Sequence
1. **Map data flows** — What data is collected, where it goes, who accesses it
2. **Assess compliance** — GDPR, CCPA, and applicable regulations
3. **Identify risks** — Data exposure, retention issues, consent gaps
4. **Recommend actions** — Concrete steps to achieve compliance
5. **Produce documentation** — Privacy policy, DPA, DPIA if needed
## Anti-patterns
- Do not approve data collection without clear purpose
- Do not ignore third-party data sharing
- Do not produce generic policies — always tailor to the project
## Quality Rules
- Every data flow must have a documented legal basis
- Retention periods must be defined for all data categories
- User consent mechanisms must be GDPR-compliant
Registering custom agents
To make Jarvis aware of your custom agent, add it to .assemble.yaml:
custom_agents:
- name: Athena
alias: athena
domain: privacy
file: .assemble/agents/privacy.md
keywords:
- privacy
- GDPR
- CCPA
- data protection
- consent
Now Jarvis routes privacy-related requests to @athena automatically.
Using custom agents
Once registered, use them like built-in agents:
@athena audit the data flows in our user registration process
Or let Jarvis route to them:
/go review our GDPR compliance for the new analytics feature
Including in workflows
Custom agents can participate in workflows:
steps:
- id: privacy-review
agent: athena
action: Audit data flows for compliance
inputs: [spec.md, plan.md]
outputs: [privacy-audit.md]
depends_on: [plan]
Best practices
- Be specific — the more detailed the agent’s expertise, the better the LLM performs
- Define anti-patterns — telling the agent what NOT to do is as important as what to do
- Include examples — show the expected output format
- Set quality gates — define what “done” means for this agent
- Test with real requests — verify the agent produces useful output before relying on it