TL;DR: Model cards document individual models—their capabilities, limitations, and intended use. System cards document how models are deployed in production systems. Together, they form the documentation foundation for responsible AI.
When something goes wrong with an AI system, the first question is: "What were you thinking?" The second question is: "What was this thing supposed to do?"
Model cards and system cards answer these questions.
Model Cards: What the Model Does
A model card is documentation for a machine learning model. Think of it as a nutrition label for AI—what's in it, what it's for, and what to watch out for.
Essential Sections
• Architecture type
• Training date
• Developers/owners
• Intended users
• Out-of-scope uses
• Known limitations
• Data preprocessing
• Data demographics
• Known gaps
• Performance across groups
• Failure modes
• Confidence calibration
The Disaggregated Metrics Principle
A model that's "95% accurate overall" might be:
- 98% accurate for majority populations
- 75% accurate for minority populations
Model cards should report performance disaggregated by:
- Demographics (age, gender, race, location)
- Use case variations
- Input quality levels
- Edge cases
System Cards: How the Model Is Used
A system card documents the production deployment—not just the model, but everything around it.
System Card vs Model Card
System Card Components
flowchart TB
subgraph SYSTEM["System Card"]
SC1[System Purpose]
SC2[Model Integration]
SC3[Human Oversight]
SC4[Operational Constraints]
SC5[Monitoring & Alerts]
SC6[Incident Response]
end
- System Purpose: What business problem does this system solve?
- Model Integration: How is the model used within the larger system?
- Human Oversight: What human review processes are in place?
- Operational Constraints: Thresholds, rate limits, fallbacks
- Monitoring: What's tracked? What triggers alerts?
- Incident Response: What happens when things go wrong?
The Gap Between Cards
The most dangerous AI systems are those where:
- The model card says "not for medical diagnosis"
- The system card (if it exists) describes a medical diagnosis system
This gap between intended use and actual use is where harm happens. System cards make this gap visible.
Who Writes These?
| Role | Model Card | System Card |
|---|---|---|
| ML Engineers | Primary author | Technical contributor |
| Product Managers | Use case sections | Primary author |
| Legal/Compliance | Reviewer | Reviewer |
| Ethics Review Board | Reviewer | Reviewer |
Living Documents
Both model cards and system cards should be:
- Version controlled: Tracked in git alongside code
- Updated: Refreshed when models or systems change
- Accessible: Available to anyone who needs them
- Linked: Model cards referenced by system cards
They're not write-once documents. They evolve with the system.
Regulatory Requirements
The EU AI Act explicitly requires documentation similar to model cards and system cards for high-risk AI systems. The terminology differs, but the requirements overlap:
- Technical documentation (Article 11)
- Instructions for use (Article 13)
- Record-keeping (Article 12)
Organizations that implement model cards and system cards now will be ahead of regulatory requirements.
Model cards answer "What can this model do?" System cards answer "How are we using it?" Together, they create accountability by making the gap between capability and deployment visible. Start with your highest-risk systems and work outward.
Empress links model cards to operational data automatically. Your static documentation stays connected to live system behavior—making audits, incident response, and compliance verification straightforward.