property-list

/tdd-pbt:property-list — Property-First Development: Property List

/tdd-pbt:property-list launches the property-list agent to identify and list properties for a feature before any implementation begins. This is Step 1 of the Property-First Development cycle.

Step 0 — Detect language

Check whether .tdd-pbt/config.yml exists in the current working directory.

If it exists: read the language field. Use it for all subsequent steps.

If it does not exist: ask the user:

AskUserQuestion:
  question: "Which language and PBT library will you use for this project?"
  header: "Language setup"
  options:
    - label: "Java + jqwik 1.9.3"
      description: "Java project using Maven, JUnit 5, and jqwik 1.9.3"
    - label: "TypeScript + fast-check + Vitest"
      description: "TypeScript project using Vitest and fast-check"

Then write .tdd-pbt/config.yml to the current working directory:

language: java   # or typescript

Confirm: "Language set to . Config written to .tdd-pbt/config.yml."

What you do

1. Collect context from the user's invocation or the current codebase state:

   • Feature description or requirements
   • Target properties file path:
     • Java: src/test/java/<package>/<ClassName>Properties.java
     • TypeScript: src/<ClassName>.properties.test.ts
   • Target implementation file path:
     • Java: src/main/java/<package>/<ClassName>.java
     • TypeScript: src/<ClassName>.ts

2. Call the property-list agent with all collected context as the prompt. Include:

   Language: <java|typescript>
   Feature: <description of what to implement>
   Properties file: <path for new properties file>
   Implementation file: <path for production code>
   

3. The agent will:

   • Analyze the feature requirements
   • Systematically identify properties across all categories (invariants, roundtrips, idempotence, symmetry, hard-to-verify, test oracle)
   • Order properties from simplest to most complex
   • Java: Create a *Properties.java file with @Disabled("todo") placeholders
   • TypeScript: Create a *.properties.test.ts file with test.todo(...) placeholders
   • Present a summary of properties with categories and descriptions

4. After the agent presents the property list, the next step is /tdd-pbt:property-red to activate the first property.

Property-First Development Cycle

/tdd-pbt:property-list  →  /tdd-pbt:property-red  →  /tdd-pbt:property-green  →  /tdd-pbt:refactor
                                    ↑_______________________________________________|
                                             (repeat for each property)

What you must NOT do

• Must not implement property bodies — only placeholders (@Disabled("todo") for Java, test.todo(...) for TypeScript).
• Must not include advanced properties in the initial list — base functionality only.
• Must not activate any property — that is the job of /tdd-pbt:property-red.
• Must not think about implementation — focus on WHAT holds true, not HOW.
• Must not write properties that reimplement the algorithm.
• Must not overwrite .tdd-pbt/config.yml if it already exists.