sourcebook-lookup

sourcebook-lookup is a skill for Claude Code, Codex from BackendGameSetMatch/sourcebook. It costs 80 tokens per session (545 once invoked), scanned A, original, MIT.

A skill for searching internal AI documentation about team processes, system behaviour, architecture decisions, and API references. It looks in documentation stored under `/docs/ai/`.

In plain words
What is it for?
It is for looking up services, build and deployment pipelines, backend or infrastructure code, conventions, decisions, APIs, and project terminology.
Why use it?
It helps an agent check existing project knowledge before making assumptions or recommending changes.

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/backendgamesetmatch/sourcebook/sourcebook-lookup
Any agent
npx skills add BackendGameSetMatch/sourcebook --skill sourcebook-lookup
Clone the repo
git clone --depth 1 https://github.com/BackendGameSetMatch/sourcebook

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 sourcebook-lookup

README.md
[![agentmods](https://agentmods.dev/badge/skills/backendgamesetmatch/sourcebook/sourcebook-lookup.svg)](https://agentmods.dev/skills/backendgamesetmatch/sourcebook/sourcebook-lookup)
Your own site
<a href="https://agentmods.dev/skills/backendgamesetmatch/sourcebook/sourcebook-lookup"><img src="https://agentmods.dev/badge/skills/backendgamesetmatch/sourcebook/sourcebook-lookup.svg" alt="Measured on agentmods" height="20"></a>
Per session 80 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 545 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 $0.00080 $0.00545
Opus 5 $0.00040 $0.00272
Sonnet 5 $0.00016 $0.00109
Haiku 4.5 $0.00008 $0.00055

Measured 5d ago against content hash a009d47f0515, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

sourcebook-lookup 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 5d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/lookup.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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/skills/sourcebook-lookup/SKILL.md · 55 lines

How it starts

The opening of the file, as written. The whole thing — 55 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AI Documentation Lookup

This project maintains structured AI-readable documentation in /docs/ai/. Consult these docs BEFORE making assumptions about how systems work, what conventions exist, what has already been decided, or which APIs we depend on.

Run the lookup script from this skill's directory:

python .claude/skills/sourcebook-lookup/scripts/lookup.py search <keywords>
python .claude/skills/sourcebook-lookup/scripts/lookup.py list [systems|processes|decisions|apis]
python .claude/skills/sourcebook-lookup/scripts/lookup.py read <path>
python .claude/skills/sourcebook-lookup/scripts/lookup.py bundle <scope>
python .claude/skills/sourcebook-lookup/scripts/lookup.py glossary [term]
python .claude/skills/sourcebook-lookup/scripts/lookup.py conventions
python .claude/skills/sourcebook-lookup/scripts/lookup.py decisions [--status active]
python .claude/skills/sourcebook-lookup/scripts/lookup.py index
python .claude/skills/sourcebook-lookup/scripts/lookup.py log

Run it with no arguments to see the full command list.

When to consult docs

  • Before modifying core service or library code - search for the system or module
  • Before integrating a new external API - load the bundle covering API references
  • Before modifying any build, deploy, or infrastructure code - load the bundle covering it
  • Before changing release workflows - read the relevant process doc
  • Before suggesting an architectural approach - list decisions
  • When encountering unfamiliar internal terms - glossary <term>
  • When unsure about constraints - conventions

Bundle names are project-specific. Passing an unknown scope to bundle prints the list this project actually defines, so check there rather than guessing a name.

Important rules

  • The decisions/ directory contains Architectural Decision Records. Always check before proposing approaches.
  • The conventions.md file contains hard constraints. Never violate these.
  • If docs seem stale (check last_verified dates), flag it rather than trusting outdated information.

Read the full file on GitHub · 55 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. 5d ago First seen · 55 lines · 80 tokens per session scan A a009d47f0515

Subscribe to this mod's changes

sourcebook-lookup is a skill published in the GitHub repository BackendGameSetMatch/sourcebook (3 stars, last pushed 23d ago), licensed MIT. It adds 80 tokens to every session and 545 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.