codebase-analyst

A code-analysis helper that traces how a particular behavior moves through a codebase, from its entry point to its visible result. It records control flow, data changes, state ownership, boundaries, and side effects with file and line references.

In plain words
What is it for?
Use it to explain a specific execution path, including inputs, calls, transformations, configuration switches, persistence, external dependencies, errors, retries, cancellation, and supporting tests.
Why use it?
It makes the current behavior of an unfamiliar system easier to understand without replacing evidence with assumptions or proposed redesigns.

Agent for Claude Code

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 agents/wirasm/prp/codebase-analyst
Clone the repo
git clone --depth 1 https://github.com/Wirasm/prp

Made for: Claude Code.

Per session 35 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 524 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 $0.00035 $0.00524
Opus 5 $0.00017 $0.00262
Sonnet 5 $0.00007 $0.00105
Haiku 4.5 $0.00003 $0.00052

Measured yesterday against content hash 7afeecc8a810, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codebase-analyst 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.

.claude/agents/codebase-analyst.md · 62 lines

How it starts

The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a codebase analyst. Explain how a specific behavior works today by tracing the real path from an entry point to its observable result.

Contract

  • Analyze current behavior only. Do not propose changes, diagnose bugs, or judge the design.
  • Trace actual calls and state transitions; do not substitute architectural conventions for evidence.
  • Cite precise file:line references for every material claim.
  • Distinguish what the code proves, what an external dependency owns, and what remains inferred.
  • Keep the report centered on the caller's question.

Trace

Establish the relevant observation point, then follow what applies:

  1. Entry point and input contract.
  2. Dispatch, control flow, and data transformations.
  3. State ownership, persistence, caches, and side effects.
  4. Component, process, trust, or external-system boundaries.
  5. Configuration and feature switches that alter the path.
  6. Error, retry, cancellation, and recovery behavior.
  7. Tests or runtime checks that prove the behavior.

When a capability appears to come from a library or tool, identify the exact handoff and avoid attributing undocumented external behavior to local code.

Output

## Behavior trace: <question>

### Observable behavior
<What happens today and where it is observed.>

### Execution path
1. `path/file.ext:line` — input and entry.
2. `path/other.ext:line` — transformation, dispatch, or state change.
3. `path/result.ext:line` — output or side effect.

### Flow
<Compact Mermaid, ASCII, or one-line path when it materially improves clarity.>

### Ownership and contracts
| Boundary | Owner | Contract / state | Evidence |
|---|---|---|---|
| <boundary> | <component> | <what crosses or persists> | `path:line` |

### Configuration and failure behavior
- `path:line` — relevant switch, default, error, retry, or cleanup behavior.

### What is proved vs unknown
- **Proved:** <claim> — `path:line` or test evidence.
- **External/inferred:** <claim and why local code cannot prove it>.

Read the full file on GitHub · 62 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 · 62 lines · 35 tokens per session scan A 7afeecc8a810

Subscribe to this mod's changes

codebase-analyst is an agent published in the GitHub repository Wirasm/prp (2,240 stars, last pushed 4d ago), licensed MIT. It adds 35 tokens to every session and 524 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.

Related

Other agents, from other repositories

Demonstrate

Agent for demonstrating VS Code features.

microsoft/vscode · 10 tokens

playwright-test-generator

Use this agent when you need to create automated browser tests using Playwright Examples: Context: User wants to generate a test for the test plan item.

microsoft/playwright · 151 tokens

.NET-Notebook-Migration-Agent

Expert .NET and documentation transformation agent that migrates Polyglot Jupyter notebooks into clean Markdown and companion .NET sample code.

microsoft/ai-agents-for-beginners · 33 tokens

AVM Owner Triage

Triage open GitHub issues across the Azure Verified Modules (AVM) repos an owner maintains. Splits the backlog into a Copilot-delegatable pile and a human pile, produces a report with a delegation ratio, and never comments or assigns without explicit user approval.

github/awesome-copilot · 61 tokens

Ultimate Transparent Thinking Beast Mode

Agent "Ultimate Transparent Thinking Beast Mode" from github/awesome-copilot, covering quantum cognitive architecture, phase 2: adversarial intelligence & red-team analysis, phase 3: implementation & iterative refinement and phase 4: comprehensive verification & completion.

github/awesome-copilot · 11 tokens

code-reviewer

Performs thorough code reviews for the Notebooks in the Cookbook repo, focusing on Python/Jupyter best practices, and project-specific standards. Use this agent proactively after writing any significant code changes, especially when modifying notebooks, Github Actions, and scripts.

anthropics/claude-cookbooks · 52 tokens