# Cmux Shared Behavior

> Shared behavior and mutation-path rules for cmux. Use when a behavior is exposed through multiple entrypoints such as keyboard shortcuts, command palette, context menu, CLI, settings, debug menu, optimistic UI, or tests that previously missed a bug.

- Skill: `manaflow-ai/cmux-shared-behavior` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add manaflow-ai/cmux-shared-behavior`
- Raw SKILL.md: https://api.skillmd.com/api/skills/manaflow-ai/cmux-shared-behavior/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: manaflow-ai (https://skillmd.com/u/manaflow-ai)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/manaflow-ai/cmux-shared-behavior

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# cmux Shared Behavior

## Shared entrypoints

When a behavior is exposed through multiple surfaces (keyboard shortcut, command palette, context menu, CLI/socket command, settings UI, debug menu), implement one shared action/model path and verify every entrypoint that should invoke it. Do not patch one surface and leave the others with duplicated logic.

## Optimistic updates

Keep one mutation path. Record pending state with a request id or a previous snapshot, reconcile from the authoritative result, and handle failure with an explicit rollback or error state. Never let each entrypoint maintain its own optimistic copy.

## Missed-bug coverage

When a user says tests missed a bug, add or adjust behavior-level coverage around the exact repro path before claiming the fix is complete.