What is agent-browser?

Browser-automation instructions for controlling an existing Chrome or Chromium tab, including one where the user is already signed in. It can also use a separate browser profile when an isolated session is needed.

Use it to automate websites in a live browser tab or in a dedicated managed browser session.

It avoids repeated logins when the task depends on the user's current cookies, extensions, or open page, while offering a separate profile when that is safer.

agent-browser — Skill for Claude Code by kwannoel/the-controller

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 kwannoel/the-controller --skill agent-browser

Clone the repo

git clone --depth 1 https://github.com/kwannoel/the-controller

Made for: Claude Code.

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/skills/kwannoel/the-controller/agent-browser/github.svg)](https://agentmods.dev/skills/kwannoel/the-controller/agent-browser)

Your own site

<a href="https://agentmods.dev/skills/kwannoel/the-controller/agent-browser"><img src="https://agentmods.dev/badge/skills/kwannoel/the-controller/agent-browser/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/kwannoel/the-controller/agent-browser"><img src="https://agentmods.dev/badge/skills/kwannoel/the-controller/agent-browser.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 59 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,505 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	$0.00059	$0.01505
Opus 5.5	$0.00024	$0.00602
Sonnet 5.5	$0.00012	$0.00301
Haiku 4.5	$0.00006	$0.00151

Measured 1mo ago against content hash 2f6d790d8aba, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

agent-browser 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.

The scan reads SKILL.md. This mod also ships 3 executable files (templates/authenticated-session.sh, templates/capture-workflow.sh, templates/form-automation.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

skills/agent-browser/SKILL.md · 224 lines

How it starts

The opening of the file, as written. The whole thing — 224 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Browser Automation with agent-browser

agent-browser is the Chromium skill. Prefer it when the user wants the agent to work against the browser they already have open and logged into.

The primary model is OpenClaw-style relay control:

Open the target site in Chrome or Chromium.
Attach the browser relay extension to the tab you want the agent to control.
Run agent-browser commands against that attached tab.
Detach when you are done.

If relay mode is unavailable, fall back to a managed dedicated browser profile.

Mode Selection

Relay mode

Use relay mode when:

the user is already logged in
the task depends on the user's real browser extensions, cookies, or in-progress state
the user wants to avoid login churn

Relay mode means the agent controls a real Chrome or Chromium tab. Treat that tab as sensitive. Use the minimum scope needed and avoid unrelated tabs.

Managed mode

Use managed mode when:

the user wants isolation from their daily browser
the relay is not installed or not attached
the task needs a dedicated automation profile

Managed mode launches or reuses a dedicated browser profile instead of the user's live browsing tab.

Core Workflow

Every agent-browser task follows this pattern:

Confirm the right tab is attached in relay mode, or start managed mode.
Snapshot the page: agent-browser snapshot -i
Interact with refs: click, fill, select, check
Re-snapshot after navigation or major DOM changes

# Attached tab is already open in Chrome/Chromium
agent-browser snapshot -i
# Output: @e1 [input type="email"], @e2 [input type="password"], @e3 [button] "Sign in"

agent-browser fill @e1 "[email protected]"
agent-browser fill @e2 "password123"
agent-browser click @e3
agent-browser wait --load networkidle
agent-browser snapshot -i

Do not close the browser in relay mode unless the user explicitly asks for that. In relay mode, prefer detach over agent-browser close.

Quick Start

Read the full file on GitHub · 224 lines

Files

What ships with it

10 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.

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.

1mo ago First seen · 224 lines · 59 tokens per session scan A 2f6d790d8aba

Subscribe to this mod's changes

agent-browser is a skill published in the GitHub repository kwannoel/the-controller (13 stars, last pushed 6mo ago), licensed MIT. It adds 59 tokens to every session and 1,505 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 2026-09-23.

Browser automation

agent-browser next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
agent-browserkwannoel/the-controller	Skill	13	6mo ago	MIT	A	59	Claude Code
interactive-loginyc-software/qm	Skill	16k	today	MIT	A	46	Claude Code, Codex
pinchtab-mcppinchtab/pinchtab	Skill	11k	yesterday	MIT	A	52	Claude Code, Codex
azure-messaging-webpubsub-javamicrosoft/skills	Skill	3.2k	yesterday	MIT	A	43	Claude Code
cua-driverdavidondrej/skills	Skill	4.3k	yesterday	MIT	A	68	Claude Code, Codex
open-design-browsercompozy/compozy	Skill	2.9k	today	MIT	A	56	Claude Code, Codex
southwestborski/travel-hacking-toolkit	Skill	931	2d ago	MIT	A	40	Claude Code