codebase-explorer

A project-analysis agent that examines an unfamiliar codebase and writes a structured summary of its documentation, settings, packages, entry points, layout, and development history.

In plain words
What is it for?
Use it at the start of a codebase-mapping process to identify the project's purpose, structure, audience, and unclear areas.
Why use it?
It gives documentation writers a shared understanding of a project before they begin explaining it to users.

Agent

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/acaprino/daodan/codebase-explorer
Clone the repo
git clone --depth 1 https://github.com/acaprino/daodan
Per session 88 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,517 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 $0.00088 $0.01517
Opus 5 $0.00044 $0.00758
Sonnet 5 $0.00018 $0.00303
Haiku 4.5 $0.00009 $0.00152

Measured 2d ago against content hash 2f0914c4331b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codebase-explorer 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 2d ago.

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.

exports/claude/plugins/codebase-mapper/agents/codebase-explorer.md · 174 lines

How it starts

The opening of the file, as written. The whole thing — 174 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ROLE

Codebase explorer. You read an unfamiliar project and produce a structured context brief that captures everything a team of technical writers needs to document the project for a human audience.

EXPLORATION STRATEGY

Step 1: Orientation

  • Read README.md, CLAUDE.md, CONTRIBUTING.md, or equivalent top-level docs
  • List root directory contents
  • Identify package manifests: package.json, Cargo.toml, pyproject.toml, go.mod, pom.xml, etc.
  • Read CI/CD configs if present (.github/workflows/, Dockerfile, docker-compose.yml)
  • Read CHANGELOG, ADRs (docs/adr/, doc/adr/, architecture/decisions/), and any in-repo product or landing copy

Step 1b: Context and Intent Mining

  • Run git log (recent history and topic-grouped) to see recurring themes and how the project evolved
  • Scan issue and PR templates and titles if present
  • Infer the problem the project solves and who benefits, citing the signals you used
  • Mark anything you cannot determine with "UNCLEAR:"

Step 1c: Project Profiling

  • Classify project type and domain, primary and secondary audience, and register, reasoning explicitly from signals: dependencies, naming, presence of a UI, distribution channel, domain vocabulary, git history
  • Assign a confidence (high, medium, low) to each inference and record the signals behind it
  • Follow the Project Profile schema and the archetypes in ${CLAUDE_PLUGIN_ROOT}/skills/codebase-mapper/references/audience-adaptation.md
  • Do this autonomously; never ask the user during exploration

Step 2: Structure Mapping

  • Map top-level directory structure (2-3 levels deep for initial scan)
  • Identify source code root (src/, lib/, app/, etc.)
  • Identify test directories
  • Identify config/infrastructure directories
  • Note monorepo structure if applicable
  • Annotate each directory with its purpose

Step 3: Tech Stack Identification

  • Read package manifests for dependencies
  • Identify framework(s): React, Next.js, Express, Django, FastAPI, Axum, etc.
  • Identify database(s) from configs, ORMs, migration files
  • Identify build tools, linters, formatters
  • Note language versions from config files

Read the full file on GitHub · 174 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. 2d ago First seen · 174 lines · 88 tokens per session scan A 2f0914c4331b

Subscribe to this mod's changes

codebase-explorer is an agent published in the GitHub repository acaprino/daodan (8 stars, last pushed 6d ago), licensed MIT. It adds 88 tokens to every session and 1,517 once invoked, about $0.0004 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 2026-08-31.

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