co9-interface-contracts

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

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

Step 2: Apply the model

// Using CO9 (Interface Contracts) - Apply the transformation
const output = applyModel("CO9", focus);

Step 3: Synthesize outcomes

// Using CO9 (Interface Contracts) - Capture insights and decisions
const insights = summarize(output);

Practical Example

// 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

{
  programs.moltbot.plugins = [
    { source = "github:hummbl-dev/​hummbl-agent?dir=skills/​CO-composition/​co9-interface-contracts"; }
  ];
}

Manual Installation

moltbot-registry install hummbl-agent/​co9-interface-contracts

Usage with Commands

/​apply-transformation CO9 "Define explicit agreements about data structures and behavior between components"

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Apply CO9 to create repeatable, explicit mental model reasoning.