core SKILL.md skillA
core from modem-dev/ossrules is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add modem-dev/ossrules/core@git:20260917.d487f87Pins git:20260917.d487f87 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- modem-dev/ossrules
- Path
public/files/agent-browser/skill-data/core/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260917.d487f87, committed Sep 17, 2026
- Size
- 37,490 bytes
- Repository stars
- 65
- License
- MIT
Core agent-browser usage guide. Read this before running any agent-browser commands. Covers the snapshot-and-ref workflow, navigating pages, interacting with elements (click, fill, type, select), extracting text and data, taking screenshots, managing tabs, handling forms and auth, waiting for content, running multiple browser sessions in parallel, and troubleshooting common failures. Use when the user asks to interact with a website, fill a form, click something, extract data, take a…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# agent-browser core
Fast browser automation CLI for AI agents. Chrome/Chromium via CDP, no Playwright or Puppeteer dependency. Accessibility-tree snapshots with compact `@eN` refs let agents interact with pages in ~200-400 tokens instead of parsing raw HTML.
Most normal web tasks (navigate, read, click, fill, extract, screenshot) are covered here. Load a specialized skill when the task falls outside browser web pages — see [When to load another skill](#when-to-load-another-skill).
## The core loop
Open the page and check the response for a WebMCP summary. If an advertised tool directly matches the authorized task, prefer that tool to reconstructing the same operation with DOM interactions. Fetch only its metadata, check the input schema and intended effect against the user request, then invoke it:
```bash
agent-browser open <url>
agent-browser webmcp list <tool> --frame <frame-id> --json
agent-browser webmcp invoke <tool> --frame <frame-id> --params '{"key":"value"}'
```
…Read the whole file at its exact version.
How to install
mdr add modem-dev/ossrules/core@sha256:670c32aa9050cc41The line at the top of this page pins the label git:20260917.d487f87, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_rvnnxro7mntvneim)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Sep 17, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (37490 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
modem-dev/ossrules · 65 stars · license MIT · pushed 2026-09-21 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_rvnnxro7mntvneim GET https://markdownregistry.com/api/v1/resolve?ref=modem-dev/ossrules/core GET https://markdownregistry.com/api/v1/blob/670c32aa9050cc41f748d990f2a16916ea5db046b048e376a30d6be21ec64c39
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
More from modem-dev/ossrules
Every file in modem-dev/ossrules