codebase-understanding

codebase-understanding is a skill for Claude Code, Codex from MikahNiehaus/ClaudeBoost. It costs 70 tokens per session (2,157 once invoked), scanned A, original, no licence file.

A method for building a structural picture of a software codebase before reviewing a proposed change. It examines relationships between imported code and checks correctness, security, testing, and maintainability.

In plain words
What is it for?
It is for mapping relevant parts of a codebase and evaluating changes against common engineering standards.
Why use it?
It helps reviewers understand how a change fits the existing system instead of judging isolated files without context.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit It is for mapping relevant parts of a codebase and evaluating changes against common engineering standards.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/mikahniehaus/claudeboost/codebase-understanding
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.

Any agent
npx skills add MikahNiehaus/ClaudeBoost --skill codebase-understanding
Clone the repo
git clone --depth 1 https://github.com/MikahNiehaus/ClaudeBoost

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for codebase-understanding

README.md
[![agentmods](https://agentmods.dev/badge/skills/mikahniehaus/claudeboost/codebase-understanding/github.svg)](https://agentmods.dev/skills/mikahniehaus/claudeboost/codebase-understanding)
Your own site
<a href="https://agentmods.dev/skills/mikahniehaus/claudeboost/codebase-understanding"><img src="https://agentmods.dev/badge/skills/mikahniehaus/claudeboost/codebase-understanding/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for codebase-understanding

Your own site · 80×15
<a href="https://agentmods.dev/skills/mikahniehaus/claudeboost/codebase-understanding"><img src="https://agentmods.dev/badge/skills/mikahniehaus/claudeboost/codebase-understanding.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 70 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,157 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 2 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 5.1 $0.00070 $0.02157
Opus 5.5 $0.00028 $0.00863
Sonnet 5.5 $0.00014 $0.00431
Haiku 4.5 $0.00007 $0.00216

Measured 8d ago against content hash 1a4a56197937, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

codebase-understanding scanned grade A with 2 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 8d 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.

Sends data to an external URLlowData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

curl -s -X POST http://127.0.0.1:8613/github-search -H "Content-Type: application/json" -d '{"query":"..."}'

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -s -X POST http://127.0.0.1:8613/search -H "Content-Type: application/json" \
clean-rag/portable/skills/codebase-understanding/SKILL.md · 169 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 8d ago First seen · 169 lines · 70 tokens per session scan A 1a4a56197937

Subscribe to this mod's changes

codebase-understanding is a skill published in the GitHub repository MikahNiehaus/ClaudeBoost (9 stars, last pushed yesterday), with no licence file. It adds 70 tokens to every session and 2,157 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-10-02.

Related

Other skills, from other repositories

adversarial-reviewer

Stress-test a code change for concrete correctness defects, unsafe assumptions, and failure modes. Use when the user explicitly asks for an adversarial review, a deep bug hunt, or to tear a change apart. Do not use for ordinary review, style feedback, or general improvement suggestions.

emdash-cms/emdash · 62 tokens

gsd-ns-review

quality gates | code review debug audit security eval ui.

open-gsd/gsd-core · 16 tokens

gitnexus

A code-graph analysis add-on for examining an existing codebase, including symbols, call paths, execution flows, and effects across repositories. It can query GitNexus through its command-line or MCP interfaces.

hashgraph-online/awesome-codex-plugins · 58 tokens

issue

Use when starting a chain from a GitHub issue — turning an issue URL or number into a triaged, planned, dispatched, and reviewed pull request. Classifies the thread (bug → root-cause discipline, feature → plan chain, question → drafted reply), synthesizes a spec from the issue's own acceptance criteria, then runs the…

jeremylongshore/tons-of-skills-marketplace · 115 tokens

cleanup-code-inspections

Reduce technical debt and improve code quality by systematically resolving static analysis warnings.

flutter/flutter-intellij · 19 tokens

superlint

This skill describes the mandatory standard operating procedure for using our internal SuperLint tool. Use this when tasks require fixing code quality issues according to corporate standards.

mgechev/skillgrade · 0 tokens