/survey-patterns

name: survey-patterns
description: "Survey the codebase for analogous features, reusable utilities, and existing patterns before a change. Use when the user asks to \"survey patterns\", \"find existing patterns\", or \"find prior art\"."

Survey Patterns

Search the codebase for analogous features and reusable building blocks before planning a change, and read any source the task names outside this repo. Returns structured findings. Does not write code or plans.

Step 1: Identify the Task

Determine what the change is about:

• If a task description was passed in, use it
• Otherwise, derive it from conversation context (the user's latest request)

State the task back in one sentence to confirm scope before searching.

Step 2: Spawn Pattern Survey Subagent

Spawn a single subagent (`model: "opus"`, no `name`). Wait for it to report before continuing; do not relaunch it if it has not yet reported. Its prompt must direct it to treat the shared working tree and its git index as read-only and to survey by reading and reasoning. Its prompt must also direct it to search the repository with a tool that skips gitignored files, such as `git grep --untracked` or the Grep tool, and to open or search a gitignored path only when its prompt or a file its prompt directs it to read names it, or when a dependency's installed source is needed to verify a claim, never one holding local configuration or credentials. HEAD stays where it is: read other refs with `git show <ref>:<path>` rather than `git checkout` or `git switch`. The subagent's prompt must include:

1. The confirmed task description from Step 1 2. An instruction to read `${CLAUDE_SKILL_DIR}/references/pattern-surveyor.md` for survey guidelines, categories, and output format before searching

The subagent covers all three categories (Analogous Features, Reusable Utilities, Convention Anchors) in one sweep, reads any external source the task names, and returns a single structured report.

Step 3: Output Findings

Output the subagent's report verbatim. Do not reformat or re-synthesize — `references/pattern-surveyor.md` specifies the exact output format the subagent produces.

Then use the TaskList tool and proceed to any remaining task.

Rules

• Do not write files.
• Do not propose implementation steps.