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Productivity · Version 1.4.0 · Reviewed 2026-08-02

Default Branch Detector

Turn engineering context into a reliable artifact for remote default detection and local-only fallback analysis with evidence, explicit trade-offs, and a verification plan.

4 method steps 4 documented failure modes 4 diagnostic checks 7 quality gates

Determines the repository default branch from authoritative remote metadata, handles detached or local-only states, and returns a machine-usable branch name with the evidence used.

₹299 one-time

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What this skill helps you do

  • Remote default detection
  • Local-only fallback analysis
  • Branch automation input

How Default Branch Detector works

You provide

Repository access, entry points, and the target change

It inspects

Real execution path for remote default detection, not naming

It decides

A local-only fallback analysis explanation with safe change seams

You verify

Claims confirmed against code paths or a test

What it checks first

Default Branch Detector determines the repository default branch from authoritative remote metadata, handles detached or local-only states, and returns a machine-usable branch name with the evidence used. Use it when the work involves Remote default detection, Local-only fallback analysis, Branch automation input.

  1. The entry points and the data flow between them, which is the fastest way to build an accurate mental model.
  2. Where behavior is actually decided, rather than where it appears to be configured.
  3. Which parts change frequently, since those carry the most current knowledge and the most risk.
  4. The seams where a change can be made safely without a wide blast radius.

Failure modes it recognizes

  • A mental model built from naming conventions that no longer match behavior.
  • Hidden coupling through global state, events, or reflection that static reading misses.
  • Dead code that appears authoritative and misleads the reader.
  • Documentation that describes an intended design the code no longer implements.

Answers it will reject

  • Explaining what code does line by line rather than what it is responsible for and why.
  • Trusting comments and documentation over the executing code path.
  • Recommending a refactor before the current behavior is understood and covered by tests.

Decision rules it applies

  • Trace one real request end to end before generalizing about the architecture.
  • Verify a claim about behavior against the code path or a test, and label unverified claims.
  • Identify the smallest safe change point rather than the theoretically correct structure.

Evidence it asks for

  • Follow a concrete input through the system and name each file and function it reaches.
  • Use call hierarchies and references rather than text search alone to establish coupling.
  • Confirm behavior with an executable test before changing it.

The method inside

  1. Establish what is actually true about remote default detection from the supplied evidence, and mark what is missing.
  2. Identify the mechanism behind local-only fallback analysis rather than restating the symptom.
  3. Choose the smallest defensible change for branch automation input, weighing impact, confidence, effort, and reversibility.
  4. Check every claim against the source

Deliverables

  • Remote default detection assessment
  • Local-only fallback analysis decision and action plan
  • Branch automation input verification checklist

Evidence requirements

  • Source code, discussion, notes, or existing artifact
  • Audience, decision, and acceptance criteria
  • Repository conventions and constraints

Quality gates

  • Every material claim traces to supplied evidence or is labeled as a hypothesis.
  • The response follows the declared deliverable contract.
  • No execution, access, measurement, or verification is invented.
  • Secrets and personal data are redacted rather than repeated.
  • The user receives a concrete independent verification step.
  • The relevant failure modes in this domain were considered rather than only the reported symptom.
  • No listed anti-pattern was recommended as a solution.

Example task

Input

Find the default branch for this repository before creating a comparison branch, and do not assume that it is named main or master.

Expected output

Read the remote symbolic HEAD or repository API first and only use local heuristics when no remote authority exists. The result includes the remote, branch name, and evidence source; an ambiguous local-only repository is reported as unresolved rather than silently guessed...

Boundaries and compatibility

Ideal for

  • Remote default detection: produce a decision or artifact grounded in supplied evidence.
  • Local-only fallback analysis: produce a decision or artifact grounded in supplied evidence.
  • Branch automation input: produce a decision or artifact grounded in supplied evidence.

Out of scope

  • Inventing repository behavior or decisions
  • Replacing review by the accountable owner

Agent compatibility

  • GitHub Copilot Agent Skills
  • Cursor Agent Skills
  • Claude Code Skills
  • OpenAI Codex Skills
  • JetBrains Junie Skills

Tool policy: Advisory by default. No tools are assumed. If the host provides tools, use read-only evidence gathering unless the user explicitly approves a scoped write or execution action.