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.
npx skills add disler/learning-cmux-with-agents --skill cmux-settingsgit clone --depth 1 https://github.com/disler/learning-cmux-with-agentsWrote 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.
[](https://agentmods.dev/skills/disler/learning-cmux-with-agents/cmux-settings)<a href="https://agentmods.dev/skills/disler/learning-cmux-with-agents/cmux-settings"><img src="https://agentmods.dev/badge/skills/disler/learning-cmux-with-agents/cmux-settings/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.
<a href="https://agentmods.dev/skills/disler/learning-cmux-with-agents/cmux-settings"><img src="https://agentmods.dev/badge/skills/disler/learning-cmux-with-agents/cmux-settings.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00110 | $0.01461 |
| Opus 5 | $0.00055 | $0.00731 |
| Sonnet 5 | $0.00022 | $0.00292 |
| Haiku 4.5 | $0.00011 | $0.00146 |
Grade B, and why
cmux-settings scanned grade B with 1 finding 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 10d 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.
Subtle steeringmediumPrompt injection
Instructions that bias recommendations or shape behaviour without the user noticing.
- Never tell the user to restart cmux to apply a change. The file watcher reloads on save. Copies of this mod
1 near-identical copy found in the catalogue:
- cmux-settings — 97% identical, 6 lines differ
How it starts
The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.
cmux-settings
cmux reads user settings from ~/.config/cmux/cmux.json (JSONC). The app installs a file watcher; saving the file applies changes immediately, no restart needed. Legacy ~/.config/cmux/settings.json is read only as a fallback for keys not present in cmux.json.
Schema: https://raw.githubusercontent.com/manaflow-ai/cmux/main/web/data/cmux.schema.json. The authoritative path list lives in Sources/CmuxSettingsJSONPathSupport.swift in the cmux checkout, and the installed skill includes a generated copy in references/all-keys.md. Top-level sections are app, terminal, notifications, sidebar, sidebarAppearance, workspaceColors, automation, browser, and shortcuts. Non-settings sections (actions, ui, commands, vault, rightSidebar) coexist in the same file.
Helper script
Use the bundled helper for every read/write. It strips JSONC comments, writes atomically, and validates keys against the schema.
# From a cmux checkout
skills/cmux-settings/scripts/cmux-settings <subcommand>
# From an installed Codex skill
~/.codex/skills/cmux-settings/scripts/cmux-settings <subcommand>
For brevity in the rest of this doc, assume the script is on $PATH as cmux-settings. To make it so for a session from a checkout: export PATH="$PWD/skills/cmux-settings/scripts:$PATH".
Subcommands:
| Command | What it does |
|---|---|
cmux-settings path |
Print the config path. |
cmux-settings dump |
Print the raw file (preserves comments). |
cmux-settings dump --no-comments |
Print the parsed JSON. |
cmux-settings get <a.b.c> |
Print value at dotted JSON path. |
cmux-settings set <a.b.c> <value> |
Set value. <value> is parsed as JSON (true, 42, "text", […], {…}); plain strings without quotes are stored as strings. |
cmux-settings unset <a.b.c> |
Delete key, reverting to the in-app default. |
cmux-settings list-supported |
List every settings JSON path the app recognizes. |
cmux-settings validate |
Parse the file and flag any unknown settings keys. |
cmux-settings open |
Open cmux.json in $EDITOR, VS Code, Cursor, or TextEdit. |
What ships with it
4 files 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.
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.
- 10d ago First seen · 84 lines · 110 tokens per session scan B 84b744c8ccc6
cmux-settings is a skill published in the GitHub repository disler/learning-cmux-with-agents (109 stars, last pushed 2mo ago), licensed MIT. It adds 110 tokens to every session and 1,461 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 1 finding (subtle steering). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
systematic-debugging
Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.
local-ai-agents
Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…
next-cache-components-adoption
Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…
insight-error-page
Write or audit an insight-kind error page for the Next.js dev overlay. Use when creating a new errors/ .mdx page, auditing an existing one, or checking that a page matches the framework fix cards. Covers page structure, title alignment, FixCard cards with Copy prompt button, code snippets, terminology verification…
next-cache-components-optimizer
Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…
next-partial-prefetching-adoption
Turn on Partial Prefetching in a Next.js app and work through the insights it surfaces. Use when the user wants to enable or adopt Partial Prefetching, flip the partialPrefetching flag, opt routes in with export const prefetch = 'partial', audit Link prefetch={true} behavior, preserve existing prefetched UI with…