I’ve been there, trying to figure out what your software can do. As a developer and architect, I’ve spent several hours defining system capabilities, and let me tell you, it’s not always as straightforward as it seems. 😅

Let me guide you through defining software capabilities that make sense. Think of capabilities as the building blocks that make your software useful - they’re what your system can do, independent of how it’s implemented.

Would you like to understand how these pieces fit together? Check out my post on the differences between capabilities, use cases, and features.

What Makes a Well-Defined Capability?

Here are the key characteristics of a well-defined capability:

  1. It’s Atomic - Does one thing well.
  2. It’s Reusable - Can be used in multiple ways.
  3. It’s Clear - Everyone understands what it does.
  4. It’s Measurable - You can prove it works.

How to Define Capabilities: Step-by-Step Guide

1. Start with Core Abilities

I begin by asking three questions:

  • What can the system do?
  • What are the fundamental operations?
  • What abilities are essential?

2. Use My Capability Template

Here’s a template that can help you define capabilities:

Name: [Clear, action-oriented name]
Description: [What this capability does]
Inputs: [What it needs to work]
Outputs: [What it produces]
Constraints: [Any limitations or requirements]

3. Validate and Refine

Before you’re done, make sure to:

  • Check if it’s clear
  • Verify it’s reusable.
  • Make sure it’s measurable.

Real-World Example: Project Management System

Let me show you a real-world example of a capability:

Name: Project Creation
Description: Creates new projects with basic information
Inputs: 
  - Project name
  - Start date
  - Team members
  - Template selection
Outputs:
  - New project record
  - Project ID
  - Creation timestamp
Constraints:
  - User must have project creation permissions
  - Project name must be unique
  - Start date must be in the future

Common Pitfalls and How to Avoid Them

Here are the mistakes I’ve made (so you don’t have to):

  1. Mixing Up Capabilities with Features

    • A feature is a specific implementation.
    • A capability is the underlying ability.
    • Want to learn more? Check out my guide on specifying software features.

  2. Being Too Broad

    • “Project Management” is too broad.
    • “Project Creation” is specific.
    • “Task Assignment” is even more specific.

  3. Missing Dependencies

    • What other capabilities are needed?
    • What external systems are required?
    • What are the prerequisites?

Best Practices I’ve Learned

  1. Start with Core Abilities

    • What can the system do?
    • What are the fundamental operations?
    • Focus on essential functions.

  2. Keep It Focused

    • One capability = one core ability
    • Break complex capabilities into smaller ones.
    • Draw clear boundaries

  3. Document Dependencies

    • What other capabilities are needed?
    • What external systems are required?
    • What are the integration points?

Advanced Tips

Want to take your capability definitions to the next level? Here’s what I’ve learned:

  1. Map Your Capabilities

    • Create a capability map.
    • Show how capabilities connect.
    • Spot gaps and overlaps

  2. Version Your Capabilities

    • Track how they evolve.
    • Document changes over time.
    • Keep a capability history.

  3. Test Thoroughly

    • Define test criteria
    • Create test scenarios
    • Verify capability behavior

Conclusion

Defining good capabilities requires discipline and practice. It’s about understanding what your system can do and documenting it clearly and effectively.

For more on related concepts, check out my posts on: