state-transition

name	state-transition
description	Use this skill when a system has discrete states, events, guards, or lifecycle phases and Codex needs transition-focused test design.
metadata	{"author":"jovd83","version":"v2.0.0","dispatcher-output-artifacts":"state_model, transition_tests, coverage_summary","dispatcher-risk":"low","dispatcher-writes-files":true,"dispatcher-input-artifacts":"requirements, states, events, guards","dispatcher-capabilities":"test-design, state-transition-analysis, lifecycle-modeling","dispatcher-stack-tags":"testing, design, state-model","dispatcher-accepted-intents":"design_state_transition_tests, model_state_machine_behavior","dispatcher-category":"testing"}

State Transition

Read First

• ./references/state-transition.md
• ./references/test-design-shared-conventions.md
• ./assets/templates/state-table.j2
• ./assets/templates/state-transition-table.j2
• ./assets/templates/test-case-list.j2

Workflow

1. Identify states, events, guards, and resulting actions.
2. Confirm the start state and invalid-transition behavior when the requirement does not make them obvious.
3. Build a transition model before writing tests.
4. Select the coverage target: all states, all transitions, or switch coverage.
5. Include invalid-transition tests when the system rejects illegal events explicitly.

Required Output

• state inventory
• transition model
• path set for the requested coverage level
• negative-transition scenarios when supported
• traceable test list

Guardrails

• Do not use state-transition testing when the requirement is really just a rule matrix or a simple range check.
• Do not invent hidden states to make the model look complete.
• Separate valid transitions from inferred invalid ones.