# co9-interface-contracts

> Apply CO9 Interface Contracts to define explicit agreements about data structures and behavior between components.

- Author: Reuben Bowlby
- Repository: hummbl-dev/hummbl-agent
- Version: 20260126123420
- Stars: 1
- Forks: 0
- Last Updated: 2026-02-06
- Source: https://github.com/hummbl-dev/hummbl-agent
- Web: https://mule.run/skillshub/@@hummbl-dev/hummbl-agent~co9-interface-contracts:20260126123420

---

---
name: co9-interface-contracts
description: Apply CO9 Interface Contracts to define explicit agreements about data structures and behavior between components.
version: 1.0.0
metadata: {"clawdbot":{"nix":{"plugin":"github:hummbl-dev/hummbl-agent?dir=skills/CO-composition/co9-interface-contracts","systems":["aarch64-darwin","x86_64-linux"]}}}
---

# CO9 Interface Contracts

Apply the CO9 Interface Contracts transformation to define explicit agreements about data structures and behavior between components.

## What is CO9?

**CO9 (Interface Contracts)** Define explicit agreements about data structures and behavior between components.

## When to Use CO9

### Ideal Situations
- Assemble components into a coherent whole
- Integrate multiple solutions into a unified approach
- Design systems that depend on clear interfaces and seams

### Trigger Questions
- "How can we use Interface Contracts here?"
- "What changes if we apply CO9 to this integrating two services?"
- "Which assumptions does CO9 help us surface?"

## The CO9 Process

### Step 1: Define the focus
```typescript
// Using CO9 (Interface Contracts) - Establish the focus
const focus = "Define explicit agreements about data structures and behavior between components";
```

### Step 2: Apply the model
```typescript
// Using CO9 (Interface Contracts) - Apply the transformation
const output = applyModel("CO9", focus);
```

### Step 3: Synthesize outcomes
```typescript
// Using CO9 (Interface Contracts) - Capture insights and decisions
const insights = summarize(output);
```

## Practical Example

```typescript
// Using CO9 (Interface Contracts) - Example in a integrating two services
const result = applyModel("CO9", "Define explicit agreements about data structures and behavior between components" );
```

## Integration with Other Transformations

- **CO9 -> DE3**: Pair with DE3 when sequencing matters.
- **CO9 -> SY8**: Use SY8 to validate or stress-test.
- **CO9 -> RE2**: Apply RE2 to compose the output.

## Implementation Checklist

- [ ] Identify the context that requires CO9
- [ ] Apply the model using explicit CO9 references
- [ ] Document assumptions and outputs
- [ ] Confirm alignment with stakeholders or owners

## Common Pitfalls

- Treating the model as a checklist instead of a lens
- Skipping documentation of assumptions or rationale
- Over-applying the model without validating impact

## Best Practices

- Use explicit CO9 references in comments and docs
- Keep the output focused and actionable
- Combine with adjacent transformations when needed

## Measurement and Success

- Clearer decisions and fewer unresolved assumptions
- Faster alignment across stakeholders
- Reusable artifacts for future iterations

## Installation and Usage

### Nix Installation
```nix
{
  programs.clawdbot.plugins = [
    { source = "github:hummbl-dev/hummbl-agent?dir=skills/CO-composition/co9-interface-contracts"; }
  ];
}
```

### Manual Installation
```bash
clawdhub install hummbl-agent/co9-interface-contracts
```

### Usage with Commands
```bash
/apply-transformation CO9 "Define explicit agreements about data structures and behavior between components"
```

---
*Apply CO9 to create repeatable, explicit mental model reasoning.*