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CommunityTools & Integrations2 starsVerified 2026-09-22

limpet

A Stop hook that keeps coding agents from quitting early: rules written in plain language are scored by Jev in about 0.7 seconds, and a violated rule sends the agent back to work instead of letting it stop.

Open github.comnoplan-inc/limpet
Category
Tools & Integrations
Published by
Community
Author
noplan-inc
Added
2026-09-22
Tagscommunitypythonclaude-codecodexcoding-agentagents

Highlights

  • Each stop sends the last three messages, this turn's tool calls, and the final message, and Jev answers one yes/no question per rule in parallel.
  • A violated rule exits 2 with a one-line reason; the second stop of the same chain is always allowed through, so the agent is pushed back at most once.
  • One Python file using only the standard library; a stop costs about 1,000 to 2,000 input tokens, roughly a hundredth of a cent.
  • Installs as a Claude Code or Codex plugin, or as a Stop hook for any agent with Claude-style hooks, with the key stored in the OS keychain.
  • suggest and calibrate read local transcripts to draft rules and report AUROC; failures exit 0 silently so a hook never blocks work.

Quickstart

bash
claude plugin marketplace add noplan-inc/limpet
claude plugin install limpet@limpet

Watch out

MIT-licensed. Needs Python 3.9+ on PATH and a TypeSafe or Vercel AI Gateway key; tested on macOS and Linux, and suggest and calibrate read transcripts of every Claude Code project and Codex session on the machine.

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