<SUBAGENT-STOP> If you were dispatched as a subagent to execute a specific task, skip this skill. </SUBAGENT-STOP> <EXTREMELY-IMPORTANT> If you think there is even a 1% chance a skill might apply to what you are doing, you ABSOLUTELY MUST invoke the skill.

IF A SKILL APPLIES TO YOUR TASK, YOU DO NOT HAVE A CHOICE. YOU MUST USE IT.

This is not negotiable. This is not optional. You cannot rationalize your way out of this. </EXTREMELY-IMPORTANT>

Instruction Priority

sdlc skills override default system prompt behavior, but user instructions always take precedence:

1. User's explicit instructions (CLAUDE.md, direct requests) — highest priority
2. sdlc skills — override default system behavior where they conflict
3. Default system prompt — lowest priority

If CLAUDE.md says "don't use TDD" and a skill says "always use TDD," follow the user's instructions. The user is in control.

How to Access Skills

In Claude Code: Use the Skill tool. When you invoke a skill, its content is loaded and presented to you—follow it directly. Never use the Read tool on skill files.

Using Skills

The Rule

Invoke relevant or requested skills BEFORE any response or action. Even a 1% chance a skill might apply means that you should invoke the skill to check. If an invoked skill turns out to be wrong for the situation, you don't need to use it.

digraph skill_flow {
    "User message received" [shape=doublecircle];
    "About to EnterPlanMode?" [shape=doublecircle];
    "Already brainstormed?" [shape=diamond];
    "Invoke brainstorm skill" [shape=box];
    "Might any skill apply?" [shape=diamond];
    "Invoke Skill tool" [shape=box];
    "Announce: 'Using [skill] to [purpose]'" [shape=box];
    "Has checklist?" [shape=diamond];
    "Create TodoWrite todo per item" [shape=box];
    "Follow skill exactly" [shape=box];
    "Respond (including clarifications)" [shape=doublecircle];

    "About to EnterPlanMode?" -> "Already brainstormed?";
    "Already brainstormed?" -> "Invoke brainstorm skill" [label="no"];
    "Already brainstormed?" -> "Might any skill apply?" [label="yes"];
    "Invoke brainstorm skill" -> "Might any skill apply?";

    "User message received" -> "Might any skill apply?";
    "Might any skill apply?" -> "Invoke Skill tool" [label="yes, even 1%"];
    "Might any skill apply?" -> "Respond (including clarifications)" [label="definitely not"];
    "Invoke Skill tool" -> "Announce: 'Using [skill] to [purpose]'";
    "Announce: 'Using [skill] to [purpose]'" -> "Has checklist?";
    "Has checklist?" -> "Create TodoWrite todo per item" [label="yes"];
    "Has checklist?" -> "Follow skill exactly" [label="no"];
    "Create TodoWrite todo per item" -> "Follow skill exactly";
}

Red Flags

These thoughts mean STOP—you're rationalizing:

Thought	Reality
"This is just a simple question"	Questions are tasks. Check for skills.
"I need more context first"	Skill check comes BEFORE clarifying questions.
"Let me explore the codebase first"	Skills tell you HOW to explore. Check first.
"I can check git/files quickly"	Files lack conversation context. Check for skills.
"Let me gather information first"	Skills tell you HOW to gather information.
"This doesn't need a formal skill"	If a skill exists, use it.
"I remember this skill"	Skills evolve. Read current version.
"This doesn't count as a task"	Action = task. Check for skills.
"The skill is overkill"	Simple things become complex. Use it.
"I'll just do this one thing first"	Check BEFORE doing anything.
"This feels productive"	Undisciplined action wastes time. Skills prevent this.
"I know what that means"	Knowing the concept ≠ using the skill. Invoke it.

Skill Catalog

Skill	When to invoke
brainstorm	New feature, creative work, before any implementation
writing-plans	After spec approval, for detailed implementation planning
plan	Adopting a Claude-native plan, or resuming work without an sdlc-format plan
pair-build	Plan exists with unchecked items — default build skill (writer + critic pair)
build	Plan exists, manual fallback (single builder, no critic)
subagent-build	Plan exists, tasks are independent, subagents available
review	Build complete, needs code review
ship	Review complete, ready for PR
finish-branch	Implementation done, need to decide merge/PR/keep/discard
parallel-dispatch	Multiple independent failures or tasks
bootstrap	Missing bin/ scripts
optimize-tests	Slow test suite
test-fixer	Test quality issues, mocked tests, missing coverage, antipatterns
performance-audit	Codebase performance audit, antipattern detection, bottleneck analysis
investigate	Production bug, "why is this broken", 500 errors, Datadog/gcloud log dive, Slack alert thread
pr-feedback	PR open, review feedback to address (automated or human)
dev	Ambiguous intent, resuming work, need state detection

Skill Priority

When multiple skills could apply, use this order:

1. Process skills first (brainstorm, debugging) - these determine HOW to approach the task
2. Workflow skills second (plan, writing-plans, pair-build, build, subagent-build, review, ship, pr-feedback, finish-branch) - these guide execution
3. Utility skills third (parallel-dispatch, bootstrap, optimize-tests, performance-audit) - these solve specific problems

"Let's build X" → brainstorm first, then workflow skills. "Fix this bug" → debugging first, then domain-specific skills.

using-sdlc vs dev

using-sdlc and dev have distinct responsibilities:

• using-sdlc = discipline layer. Always active. Ensures every user message is checked against the skill catalog before responding. Routes to the right skill based on intent.
• dev = detection layer. Invoked explicitly via /sdlc:dev or when using-sdlc can't determine the right skill from intent alone. Runs diagnostics (branch state, plan status, gate results, PR status) to recommend the next phase.

When using-sdlc routes directly: User intent is clear — "let's brainstorm", "review this", "create a PR".

When using-sdlc defers to dev: User intent is ambiguous — "let's work on this", "what's next", "continue", or resuming a session mid-work.

Skill Types

Rigid (TDD, debugging): Follow exactly. Don't adapt away discipline.

Flexible (patterns): Adapt principles to context.

The skill itself tells you which.

User Instructions

Instructions say WHAT, not HOW. "Add X" or "Fix Y" doesn't mean skip workflows.