A read-only tool for inspecting running tmux terminal sessions and panes. It can list active sessions, show current output, or wait until a pane changes.

Use it to inspect terminal output, check whether a development server or test watcher is progressing, and monitor a pane for changes.

It lets an agent check servers, test watchers, and other running processes without sending keystrokes or changing their state.

observe — Command for Claude Code by MadAppGang

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.

Clone the repo

git clone --depth 1 https://github.com/MadAppGang/magus

Made for: Claude Code.

Or install terminal, the plugin that ships this one along with the rest of its 5 skills, 7 commands, 1 agent.

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.

README.md

[![agentmods](https://agentmods.dev/badge/commands/madappgang/magus/observe.svg)](https://agentmods.dev/commands/madappgang/magus/observe)

Your own site

<a href="https://agentmods.dev/commands/madappgang/magus/observe"><img src="https://agentmods.dev/badge/commands/madappgang/magus/observe.svg" alt="Measured on agentmods" height="20"></a>

Per session 28 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 772 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.

Model	Per session	Once invoked
Fable 5.1	$0.00028	$0.00772
Opus 5	$0.00014	$0.00386
Sonnet 5	$0.00006	$0.00154
Haiku 4.5	$0.00003	$0.00077

Measured 3d ago against content hash 27ab25c72607, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

observe 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 3d 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.

plugins/terminal/commands/observe.md · 89 lines

How it starts

The opening of the file, as written. The whole thing — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/terminal:observe

Read-only observation of running terminal sessions. List what's active, capture pane content, and check on processes without modifying anything.

Usage

/terminal:observe
/terminal:observe {paneId}
/terminal:observe {paneId} --watch

Pane IDs use the format %N (e.g., %3) or headless:%N (e.g., headless:%0).

What It Does

No arguments: Lists all tmux sessions/panes, captures the most active pane
With pane ID (%N or headless:%N): Captures the specified pane content
With --watch flag: Uses watch-pane to monitor until a change event fires

This is strictly read-only — it never sends keystrokes, kills sessions, or modifies state.

Examples

Check what's running:

/terminal:observe

Lists all active sessions and shows a snapshot of the most recent pane.

Check on a dev server started earlier:

/terminal:observe %3

Captures the pane to see current server output.

Read a developer's tmux pane:

/terminal:observe %5

Captures the content of a specific pane in the developer's tmux environment.

Monitor a pane until something changes:

/terminal:observe %3 --watch

Blocks via watch-pane until an error, exit, or 30s of idle activity.

Workflow: Check on a /terminal:watch Process

After starting a process with /terminal:watch, use /terminal:observe later to check its status:

1. /terminal:watch "bun run dev"     → Reports ready; paneId: %3
2. ... work on other things ...
3. /terminal:observe %3              → Shows current server output

Read Existing tmux Environment

To read the developer's running terminals:

1. /terminal:observe              → Lists all tmux sessions and panes
2. /terminal:observe %5           → Reads specific pane by ID

Safety: Never kill or modify the developer's tmux sessions. This command is observe-only.

Implementation

If no argument: call list-sessions, list-windows, list-panes; capture the active pane
If pane ID: call capture-pane({ paneId, lines: 50 }) with that pane ID
If --watch: call watch-pane({ paneId, triggers: "exit,error,idle:30", timeout: 120 })
To check process state: call pane-state({ paneId }) — returns OS-level process info

Read the full file on GitHub · 89 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.

3d ago First seen · 89 lines · 28 tokens per session scan A 27ab25c72607

Subscribe to this mod's changes

observe is a command published in the GitHub repository MadAppGang/magus (9 stars, last pushed 3d ago), licensed MIT. It adds 28 tokens to every session and 772 once invoked, about $0.0001 per session on Opus 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 2026-09-04.

DevOps and cloud Testing

qa-changes

This skill should be used when the user asks to "QA a pull request", "test PR changes", "verify a PR works", "functionally test changes", or when an automated workflow triggers QA validation of code changes. Provides a structured methodology for setting up the environment, exercising changed behavior, and reporting…

OpenHands/extensions · 63 tokens

observe