rethink

rethink is a skill for Claude Code from agenticnotetaking/arscontexta. It costs 51 tokens per session (6,267 once invoked), scanned A, original, MIT.

A review command for questioning assumptions in an accumulated knowledge system using observations, conflicts, and evidence. It looks for patterns and suggests proposals for improving the system.

In plain words
What is it for?
Use it to review observations, investigate tensions, challenge assumptions, identify patterns, and propose changes to the knowledge system.
Why use it?
It helps reveal when current methods or beliefs no longer fit what the stored evidence shows.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: mentions CLAUDE.md; names the AskUserQuestion tool.

Part of the arscontexta plugin — 26 skills, 1 agent, 2 hooks shipped together

Good fit Use it to review observations, investigate tensions, challenge assumptions, identify patterns, and propose changes to the knowledge system.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/agenticnotetaking/arscontexta/rethink
About the project

Ars Contexta is a Claude Code plugin that creates a personalized knowledge system from a conversation about how someone thinks and works, using connected Markdown files, note-processing skills, hooks, navigation maps, and templates. It is for people who want an owned, persistent second brain tailored to their domain. The catalogue entries are its generated skills, hooks, agent, and plugin workflow.

agenticnotetaking/arscontexta · 3,509 stars · on GitHub · arscontexta.org

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 agenticnotetaking/arscontexta --skill rethink
Clone the repo
git clone --depth 1 https://github.com/agenticnotetaking/arscontexta

Made for: Claude Code.

Or install arscontexta, the plugin that ships this one along with the rest of its 26 skills, 1 agent, 2 hooks.

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 rethink

README.md
[![agentmods](https://agentmods.dev/badge/skills/agenticnotetaking/arscontexta/rethink/github.svg)](https://agentmods.dev/skills/agenticnotetaking/arscontexta/rethink)
Your own site
<a href="https://agentmods.dev/skills/agenticnotetaking/arscontexta/rethink"><img src="https://agentmods.dev/badge/skills/agenticnotetaking/arscontexta/rethink/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 rethink

Your own site · 80×15
<a href="https://agentmods.dev/skills/agenticnotetaking/arscontexta/rethink"><img src="https://agentmods.dev/badge/skills/agenticnotetaking/arscontexta/rethink.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 6,267 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. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Excessive Agency · line 226
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
How audits are shown
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 $0.00051 $0.06267
Opus 5.5 $0.00020 $0.02507
Sonnet 5.5 $0.00010 $0.01253
Haiku 4.5 $0.00005 $0.00627

Measured 1mo ago against content hash 99d1c30741dc, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

rethink 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.

skill-sources/rethink/SKILL.md · 658 lines

How it starts

The opening of the file, as written. The whole thing — 658 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Runtime Configuration (Step 0 — before any processing)

Read these files to configure domain-specific behavior:

  1. ops/derivation-manifest.md — vocabulary mapping, domain context

    • Use vocabulary.notes for the notes folder name
    • Use vocabulary.note for the note type name in output
    • Use vocabulary.rethink for the command name in output
    • Use vocabulary.topic_map for MOC references
    • Use vocabulary.cmd_reflect for connection-finding references
  2. ops/config.yaml — thresholds, processing preferences

    • self_evolution.observation_threshold: number of pending observations before suggesting rethink (default: 10)
    • self_evolution.tension_threshold: number of pending tensions before suggesting rethink (default: 5)
  3. ops/methodology/ — existing methodology notes (read all to understand current system self-knowledge)

If these files don't exist (pre-init invocation or standalone use), use universal defaults.

The command name itself transforms per domain. The derivation manifest maps the universal name to domain-native language. If no manifest exists, use "rethink" as the command name.

EXECUTE NOW

Target: $ARGUMENTS

Parse immediately:

  • If target is empty: run full six-phase rethink (Phase 0 drift check + five evidence phases) on all pending observations and tensions
  • If target is "triage": run Phase 1 only (triage and methodology updates, no pattern detection)
  • If target is "patterns": skip triage, run Phases 3-5 only (analyze existing evidence for patterns)
  • If target is "drift": run Phase 0 only (drift check without triage or pattern detection)
  • If target is a specific observation or tension filename: triage that single item interactively

START NOW. Reference below defines the six-phase workflow.


Philosophy

The system is not sacred. Evidence beats intuition.

Every rule in the context file, every workflow in a skill, every assumption baked into the architecture was a hypothesis at some point. Hypotheses need testing against reality. Observation notes in ops/observations/ capture friction from actual use. Tension notes in ops/tensions/ capture unresolved conflicts. Rethink first triages these individually (some become {DOMAIN:notes}, some become methodology updates, some get archived), then compares remaining evidence against what the system assumes and proposes changes when patterns emerge.

Read the full file on GitHub · 658 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. 1mo ago First seen · 658 lines · 51 tokens per session scan A 99d1c30741dc

Subscribe to this mod's changes

rethink is a skill published in the GitHub repository agenticnotetaking/arscontexta (3,509 stars, last pushed 7mo ago), licensed MIT. It adds 51 tokens to every session and 6,267 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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