extraction

extraction is a skill for Claude Code, Codex from alphabravo-oss/guild. It costs 35 tokens per session (638 once invoked), scanned A, original, MIT.

Guidance for deciding which documentation should be generated from a source of truth and which explanation should be written by hand. A source of truth is the authoritative code, specification, or configuration that the documentation describes.

In plain words
What is it for?
Use it when documenting APIs, types, configuration, schemas, Python APIs, or Go packages, and when choosing extraction tools.
Why use it?
It reduces outdated reference pages caused by copying technical details manually. It also separates generated facts from human explanations about purpose and alternatives.

Skill for Claude CodeCodex

Part of the webster plugin — 11 skills, 6 agents shipped together

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/alphabravo-oss/guild/extraction
Any agent
npx skills add alphabravo-oss/guild --skill extraction
Clone the repo
git clone --depth 1 https://github.com/alphabravo-oss/guild

Made for: Claude Code, Codex.

Or install webster, the plugin that ships this one along with the rest of its 11 skills, 6 agents.

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 extraction

README.md
[![agentmods](https://agentmods.dev/badge/skills/alphabravo-oss/guild/extraction.svg)](https://agentmods.dev/skills/alphabravo-oss/guild/extraction)
Your own site
<a href="https://agentmods.dev/skills/alphabravo-oss/guild/extraction"><img src="https://agentmods.dev/badge/skills/alphabravo-oss/guild/extraction.svg" alt="Measured on agentmods" height="20"></a>
Per session 35 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 638 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 5.1 $0.00035 $0.00638
Opus 5 $0.00017 $0.00319
Sonnet 5 $0.00007 $0.00128
Haiku 4.5 $0.00003 $0.00064

Measured yesterday against content hash 10cd80e40412, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

extraction 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.

plugins/webster/skills/extraction/SKILL.md · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Extraction

The rule

A reference page is extracted, not written.

A model writing an API reference from a code read produces a table that is correct on the day and wrong by the next commit, because nothing regenerates it. An extractor cannot drift, because it is re-run against the source of truth.

What a person adds around the extracted output is the part worth writing by hand: why this endpoint exists, what it refuses to do, what the reader should reach for instead. That is explanation, and it belongs on a different page from the reference.

What comes from where

Reference material Source of truth Tool
Exported TypeScript types The types typedoc
Public API surface of a package The types @microsoft/api-extractor, which also reports surface changes between versions
HTTP endpoints, with an OpenAPI spec The spec @scalar/api-reference to render, redocly lint to govern
HTTP endpoints, no spec The route files scripts/survey.py, which enumerates them with anchors
Environment and config .env.example and the loader scripts/survey.py
Python API Docstrings mkdocstrings
Go packages The source go doc
Changelog Commits and tags The changelog skill

Run scripts/survey.py first. Its tooling block names the extractors that fit this repo and the exact command for each.

When there is no spec and no extractor

This is the common case for an app rather than a library, and it is where invention happens.

  1. Take the surface from scripts/survey.py. Every entry carries a file:line anchor.
  2. Read each handler. Do not summarise from the route name.
  3. Request and response shapes come from the types or the validation code, quoted with anchors. If neither exists, the shape is [?] and says so.
  4. Status codes come from the code paths that return them, not from convention. A 429 that is documented but never returned is worse than an undocumented one.
  5. Never document a field you cannot point at.

Read the full file on GitHub · 60 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 · 60 lines · 35 tokens per session scan A 10cd80e40412

Subscribe to this mod's changes

extraction is a skill published in the GitHub repository alphabravo-oss/guild (2 stars, last pushed 3d ago), licensed MIT. It adds 35 tokens to every session and 638 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 2026-09-04.

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