codebase-exploration-loop

A guided process for understanding an unfamiliar codebase, meaning the collection of source files that make up a software project.

In plain words
What is it for?
Use it during onboarding, reverse-engineering, or when you need to answer detailed questions about how an unfamiliar repository is organized.
Why use it?
It turns scattered reading into a written architecture summary, with answers tied to specific places in the code.

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/ivy00johns/skill-madness/codebase-exploration-loop
Any agent
npx skills add ivy00johns/Skill-Madness --skill codebase-exploration-loop
Clone the repo
git clone --depth 1 https://github.com/ivy00johns/Skill-Madness

Made for: Claude Code, Codex.

Per session 205 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,641 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 $0.00205 $0.02641
Opus 5 $0.00102 $0.01321
Sonnet 5 $0.00041 $0.00528
Haiku 4.5 $0.00020 $0.00264

Measured 2d ago against content hash 3f33cb76c7ca, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codebase-exploration-loop 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.

skills/loops/codebase-exploration-loop/SKILL.md · 180 lines

How it starts

The opening of the file, as written. The whole thing — 180 lines — stays where its author put it; the contents beside it link to each section on GitHub.

codebase-exploration-loop

A configuration of [loop-controller]. That skill supplies the loop machinery — primitive selection, the full guardrail stack, state externalization. This skill supplies the three things specific to "understand this codebase": the seed-question proof (a default-FAIL question list that only flips on a code citation), the read-only fan-out that maps subsystems in parallel, and the loop-until-dry stop on remaining understanding gaps. Read loop-controller for the guardrails; they're inherited, not repeated here.

Why disable-model-invocation: this loop spends tokens fanning out a wave of subagents per iteration, repeatedly, until your questions are answered. It is user-driven — you want to type /codebase-exploration-loop with your questions, not have Claude silently launch an exploration swarm because you asked a passing question about a file.

The 5-part contract

Part This loop
trigger "I don't understand X" about an unfamiliar repo — onboarding, reverse-engineering, or an explicit /codebase-exploration-loop with a list of seed questions
action ONE round: read the gap list → fan out read-only subagents (one per open subsystem/question, parallelism capped) → each returns findings + file:line citations → synthesize into the architecture summary → mark answered questions, surface newly-discovered gaps
proof the architecture summary answers every seed question, each answer citing a path:line (or symbol) in the code, with zero open "I don't understand X" gaps — default-FAIL: every question starts answered: false and flips only on a citation
memory seed-questions.json (the default-FAIL question list + the new gaps each round surfaces) and ARCHITECTURE-SUMMARY.md (the growing synthesis) — durable across rounds; no reliance on conversation memory
stop every question answered: true with a citation OR loop-until-dry (a round surfaces no new gaps and answers nothing new) OR iteration/round cap OR no-progress for 2 rounds OR budget cap

Read the full file on GitHub · 180 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 180 lines · 205 tokens per session scan A 3f33cb76c7ca

Subscribe to this mod's changes

codebase-exploration-loop is a skill published in the GitHub repository ivy00johns/Skill-Madness (11 stars, last pushed 22d ago), licensed MIT. It adds 205 tokens to every session and 2,641 once invoked, about $0.0010 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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