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 agentmods add skills/coleam00/archon/agent-browsernpx skills add coleam00/Archon --skill agent-browsergit clone --depth 1 https://github.com/coleam00/ArchonWhat 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 | $0.00051 | $0.02169 |
| Opus 5 | $0.00026 | $0.01085 |
| Sonnet 5 | $0.00010 | $0.00434 |
| Haiku 4.5 | $0.00005 | $0.00217 |
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 yesterday.
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.
How it starts
The opening of the file, as written. The whole thing — 272 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Browser Automation with agent-browser
Installation
agent-browser is an external tool by Vercel Labs. It is not bundled with Archon and must be installed separately.
Optional dependency — Only needed for E2E/UI testing workflows (
archon-validate-pr,validate-uiskill,replicate-issueskill). Core Archon functionality works without it.
# Install globally
npm install -g agent-browser
# Download browser engine (Chrome for Testing)
agent-browser install
Platform notes:
- Docker: Already included in the Archon Docker image — no action needed
- Windows: Has a known bug with Unix domain sockets. Use WSL as a workaround — see E2E Testing on WSL
- macOS/Linux: Works natively after install
For full setup details, see E2E Testing Guide.
Quick start
agent-browser open <url> # Navigate to page
agent-browser snapshot -i # Get interactive elements with refs
agent-browser click @e1 # Click element by ref
agent-browser fill @e2 "text" # Fill input by ref
agent-browser close # Close browser
Core workflow
- Navigate:
agent-browser open <url> - Snapshot:
agent-browser snapshot -i(returns elements with refs like@e1,@e2) - Interact using refs from the snapshot
- Re-snapshot after navigation or significant DOM changes
Commands
Navigation
agent-browser open <url> # Navigate to URL
agent-browser back # Go back
agent-browser forward # Go forward
agent-browser reload # Reload page
agent-browser close # Close browser
Snapshot (page analysis)
agent-browser snapshot # Full accessibility tree
agent-browser snapshot -i # Interactive elements only (recommended)
agent-browser snapshot -c # Compact output
agent-browser snapshot -d 3 # Limit depth to 3
agent-browser snapshot -s "#main" # Scope to CSS selector
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.
- yesterday First seen · 272 lines · 51 tokens per session scan A 1b2d268c7aba
agent-browser is a skill published in the GitHub repository coleam00/Archon (23,313 stars, last pushed yesterday), licensed MIT. It adds 51 tokens to every session and 2,169 once invoked, about $0.0003 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 2026-08-30.
Other skills, from other repositories
system-prompts
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tool-prompt-optimization
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semantic-compression
Re-encode verbose prose into a dense telegraphic register — punctuation as connectives, label frames, verbless assertions — without losing normativity or precision. Use when compressing system prompts, tool/function descriptions, skill bodies, or agent instructions; reducing token count or context bloat; making…
greet
A greeting skill for testing.
lab-qc-presentation-theme
Use when creating or restyling German HTML/CSS/JS presentations for chemical production quality-control laboratory audiences: laboratory technicians, scientists, and/or quality-control teamleaders. Reproduces a modern professional green laboratory theme while regenerating content only from the current source material.
getdesign
Turn any public URL into a production-grade 9-section design.md spec (colors, typography, components, layout, depth, motion, responsive, prompt guide) using the agent's own built-in tools — WebFetch, browser/screenshot, and file writes. Use when the user asks to "generate a design system from a URL", "extract brand…