prp-codebase-question

A research workflow for answering questions about what already exists in a codebase. It uses parallel agents and requires claims to be tied to specific files and lines.

In plain words
What is it for?
Use it to find where code lives, explain how components work together, trace an existing workflow, and produce a referenced description of the current implementation.
Why use it?
It helps developers understand an unfamiliar project without mixing factual documentation with proposed changes or speculation.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/wirasm/prp/prp-codebase-question
Any agent
npx skills add Wirasm/prp --skill prp-codebase-question
Clone the repo
git clone --depth 1 https://github.com/Wirasm/prp

Made for: Claude Code, Codex.

Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,858 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00047 $0.02858
Opus 5 $0.00023 $0.01429
Sonnet 5 $0.00009 $0.00572
Haiku 4.5 $0.00005 $0.00286

Measured yesterday against content hash 4c3ba12d2ef0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prp-codebase-question scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/prp-codebase-question/SKILL.md · 398 lines

How it starts

The opening of the file, as written. The whole thing — 398 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Arguments: $ARGUMENTS (and $1, $2, ...) refer to the arguments given when this skill was invoked. Take them from the user's request; if absent, infer them from the conversation.

Codebase Research

Input: $ARGUMENTS


Your Mission

Answer codebase questions thoroughly by spawning parallel specialized agents, synthesizing their findings, and producing a research document.

Core Philosophy: Document what IS, not what SHOULD BE. You are a technical cartographer.

Golden Rule: Every claim must have a file:line reference. No speculation, no suggestions, no critique.


CRITICAL: Documentarian Only

  • DO NOT suggest improvements or changes
  • DO NOT perform root cause analysis unless explicitly asked
  • DO NOT propose future enhancements
  • DO NOT critique implementations or identify problems
  • DO NOT recommend refactoring or optimization
  • ONLY describe what exists, where it exists, how it works, and how components interact

Phase 1: PARSE - Understand the Query

1.1 Read Mentioned Files

If the user mentions specific files, read them FULLY first (no limit/offset) before any decomposition.

1.2 Classify the Query

Type Indicators Agent Focus
Where "where is", "find", "locate" codebase-explorer primary
How "how does", "trace", "flow" codebase-analyst primary
What "what is", "explain", "describe" Both agents in parallel
Pattern "how do we", "convention", "examples" codebase-explorer primary
External "docs", "best practice", "API" Add web-researcher

1.3 Determine Scope

  • Identify specific components, patterns, or concepts to investigate
  • Note any --web flag for external research
  • Note any --follow-up flag for appending to existing research

PHASE_1_CHECKPOINT:

  • Mentioned files read in full
  • Query type classified
  • Research scope identified
  • Flags parsed (--web, --follow-up)

Read the full file on GitHub · 398 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 398 lines · 47 tokens per session scan A 4c3ba12d2ef0

Subscribe to this mod's changes

prp-codebase-question is a skill published in the GitHub repository Wirasm/prp (2,240 stars, last pushed 4d ago), licensed MIT. It adds 47 tokens to every session and 2,858 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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