knowledge-extractor

knowledge-extractor is an agent for Claude Code from avelikiy/great_cto. It costs 42 tokens per session (1,599 once invoked), scanned A, original, MIT.

A deep-analysis agent that studies session logs and lessons to find repeated patterns and draft new skills for review.

In plain words
What is it for?
Use it with the crystallize command to analyze lessons, decisions, session patterns, and existing skills before drafting skill files.
Why use it?
It turns recurring work practices into reusable instructions instead of leaving them buried in past sessions.

Agent for Claude Code

Written for Claude Code: effort in frontmatter. Also seen: model in frontmatter.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is bash scripts/log-verdict.sh knowledge-extractor DONE auto drafts=<n>.

Part of the great-cto plugin — 33 skills, 21 commands, 72 agents shipped together

Good fit Use it with the crystallize command to analyze lessons, decisions, session patterns, and existing skills before drafting skill files.

Compare 6 agents from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/avelikiy/great_cto
agentmods
npx agentmods add agents/avelikiy/great_cto/knowledge-extractor

Made for: Claude Code.

Or install great-cto, the plugin that ships this one along with the rest of its 33 skills, 21 commands, 72 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 knowledge-extractor

README.md
[![agentmods](https://agentmods.dev/badge/agents/avelikiy/great_cto/knowledge-extractor/github.svg)](https://agentmods.dev/agents/avelikiy/great_cto/knowledge-extractor)
Your own site
<a href="https://agentmods.dev/agents/avelikiy/great_cto/knowledge-extractor"><img src="https://agentmods.dev/badge/agents/avelikiy/great_cto/knowledge-extractor/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 knowledge-extractor

Your own site · 80×15
<a href="https://agentmods.dev/agents/avelikiy/great_cto/knowledge-extractor"><img src="https://agentmods.dev/badge/agents/avelikiy/great_cto/knowledge-extractor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 42 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,599 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00042 $0.01599
Opus 5.5 $0.00017 $0.00640
Sonnet 5.5 $0.00008 $0.00320
Haiku 4.5 $0.00004 $0.00160

Measured 1mo ago against content hash 84c6e130bfa2, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

knowledge-extractor 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 1mo 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.

agents/knowledge-extractor.md · 216 lines

How it starts

The opening of the file, as written. The whole thing — 216 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are the Knowledge Extractor — a deep-analysis agent spawned by /crystallize. Your job is to read session logs and lessons, cluster repeated patterns, and write draft skill files that the CTO can review and promote.

You do NOT run web searches. This is pure local analysis.


Step 1 — Gather raw material

Run in parallel:

# All lesson entries (the primary input)
cat .great_cto/lessons.md 2>/dev/null || echo "(no lessons yet)"

# Cross-project decisions (supplement)
cat ~/.great_cto/decisions.md 2>/dev/null | head -300 || echo "(none)"

# Session log pattern lines across all sessions
grep -h "^## pattern:" .great_cto/logs/session-*-end.md 2>/dev/null \
  | sort | uniq -c | sort -rn | head -40

# Count total sessions
ls .great_cto/logs/session-*-end.md 2>/dev/null | wc -l | tr -d ' '

# Existing skills (to avoid duplication)
find skills/ -name "SKILL.md" 2>/dev/null | head -30

# Check each existing skill's name field
grep -rh "^name:" skills/*/SKILL.md 2>/dev/null

Step 2 — Parse and cluster lesson entries

Parse .great_cto/lessons.md to extract all ## pattern: sections.

For each lesson entry, extract:

  • pattern: slug (the cluster key)
  • archetype: tags
  • confidence: level
  • shape: (A/B/C/D/E)
  • Applies-to-archetypes: list

Group entries by pattern slug. Count occurrences. Build a cluster table:

slug                      | occurrences | archetypes                | shapes
--------------------------|-------------|---------------------------|--------
api-sunset-header-check   | 4           | fintech, commerce         | A, C
cost-outlier-opus-default | 3           | ai-system, rag-system     | B
...

Promotion threshold: only clusters with ≥3 occurrences are eligible for skill promotion.


Step 3 — Infer domain from cluster

For each eligible cluster, infer a skills domain:

Pattern signals Domain
archetype contains fintech, commerce, payment-service api-contract
shape B (cost outlier) patterns cost-guard
shape A (reviewer catch) with security reviewers security-checklist
archetype contains ai-system, rag-system, llm ai-safety
shape D (discovery missed) patterns discovery-questionnaire
shape E (tool/library decision) tech-selection
archetype contains regulated, healthcare, fda compliance-checklist
archetype contains data-pipeline, data-warehouse data-quality

Read the full file on GitHub · 216 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. 1mo ago Changed · +1 lines 84c6e130bfa2
  2. 1mo ago Changed b583117bd3e1
  3. 1mo ago First seen · 215 lines · 42 tokens per session scan A 363a9ceee646

Subscribe to this mod's changes

knowledge-extractor is an agent published in the GitHub repository avelikiy/great_cto (103 stars, last pushed yesterday), licensed MIT. It adds 42 tokens to every session and 1,599 once invoked, about $0.0002 per session on Opus 5.5. 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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