plasmate CLAUDE.md

plasmate CLAUDE.md is an instructions file for coding agents from plasmate-labs/plasmate. It costs 46,753 tokens per session, scanned A, original, Apache-2.0.

Instructions for Plasmate, a browser engine that fetches web pages and turns their HTML into structured data for AI agents.

In plain words
What is it for?
Use it to fetch pages, extract readable text, send custom request headers, run the browser service, or start its MCP server.
Why use it?
It gives contributors and users clear commands for building, running, testing, and connecting Plasmate to coding tools.

Instructions file

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.

agentmods
npx agentmods add instructions/plasmate-labs/plasmate/claude-md
Clone the repo
git clone --depth 1 https://github.com/plasmate-labs/plasmate

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.

agentmods badge for plasmate CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/plasmate-labs/plasmate/claude-md.svg)](https://agentmods.dev/instructions/plasmate-labs/plasmate/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/plasmate-labs/plasmate/claude-md"><img src="https://agentmods.dev/badge/instructions/plasmate-labs/plasmate/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 46,753 This file is loaded in full into every session.
When invoked 46,753 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5 $0.46753 $0.46753
Opus 5 $0.23377 $0.23377
Sonnet 5 $0.09351 $0.09351
Haiku 4.5 $0.04675 $0.04675

Measured 5d ago against content hash 49b624d358e5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

plasmate CLAUDE.md 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 5d 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.

CLAUDE.md · 3,048 lines

How it starts

The opening of the file, as written. The whole thing — 3,048 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Plasmate

The browser engine for AI agents. HTML in, Semantic Object Model out.

Quick Start

# Build
cargo build --release

# Run
./target/release/plasmate fetch https://example.com

# MCP mode (for Claude Code, Cursor, etc.)
./target/release/plasmate mcp

Architecture

  • src/main.rs - CLI entry point (Clap)
  • src/network/ - HTTP fetch with H1/H2 fallback, custom headers
  • src/som/ - Semantic Object Model compiler (HTML to structured JSON)
  • src/cdp/ - Chrome DevTools Protocol server
  • src/awp/ - Agent Web Protocol handler
  • src/bench/ - Benchmarking runner
  • src/js/ - V8 JavaScript execution engine
  • website/ - plasmate.app homepage
  • integrations/ - Framework adapters (Vercel AI, LangChain, browser-use)

Key Commands

  • plasmate fetch <url> - Fetch URL, output SOM JSON
  • plasmate fetch <url> --text - Extract readable text only
  • plasmate fetch <url> -H "Authorization: Bearer ..." - Fetch with custom headers
  • plasmate serve - Start CDP server
  • plasmate mcp - Start MCP server (stdio)
  • plasmate bench <url> - Run benchmarks

Testing

cargo test
cargo check

Version

Version is derived from Cargo.toml via env!("CARGO_PKG_VERSION"). Do not hardcode version strings.

Running State

2026-05-17T07:06:05Z - Plasmate Improvements Automation

  • Git sync: required git fetch --prune origin was attempted first in the linked automation worktree and failed because shared worktree metadata FETCH_HEAD could not be opened (Operation not permitted). Fallback fetch from /Users/steve/Git/plasmate failed DNS for github.com, so work continued from the already-local HEAD/origin/master 11eda59.
  • Market direction: current trend research still supports the local-first SOM wedge. Browserbase/Stagehand emphasizes act/extract/observe/agent, action caching, session replay, prompt observability, and local-to-cloud portability; Cloudflare Browser Rendering added CDP endpoints plus MCP client support; Firecrawl continues packaging scrape/search/extract and browser interaction through MCP surfaces. No hosted-browser pivot is recommended; the sticky move is making ordinary CDP clients resolve SOM-backed action targets with selectors and node attributes before raw DOM recovery.
  • Code changes: CDP DOM.querySelector / DOM.querySelectorAll now support tag-qualified and bare attribute selectors for name, href, type, aria-label, aria-labelledby, aria-describedby, role, test ids, and boolean availability attrs. Text/label matching is now case-insensitive. CDP DOM nodes now expose replay attributes such as data-plasmate-id, data-som-role, HTML id, test id, ARIA label, href/name/type, and disabled/readonly/required flags when available.
  • Docs changes: README, PRD, roadmap source docs, and generated website docs now document the CDP attribute-selector rationale and selector/node-attribute compatibility contract.
  • Verification passed: touched-file rustfmt check, focused cargo test cdp::, node website/build.mjs with the primary-checkout website/node_modules symlink removed afterward, git diff --check, cargo build --quiet, cargo test --lib --quiet (281), and cargo clippy --quiet with existing warnings.
  • Verification blocked: full cargo test --quiet still fails only in sandboxed tests/awp_integration_test.rs because local listener setup returns Operation not permitted.
  • Commit/push state: alternate-index commit 31dc7c1 (chore: improve CDP attribute selector parity) was pushed to remote master and to origin/codex/plasmate-improvements-2026-05-17-cdp-attribute-selectors.

Read the full file on GitHub · 3,048 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.

  1. 5d ago First seen · 3,048 lines · 46,753 tokens per session scan A 49b624d358e5

Subscribe to this mod's changes

plasmate CLAUDE.md is an instructions file published in the GitHub repository plasmate-labs/plasmate (36 stars, last pushed today), licensed Apache-2.0. It adds 46,753 tokens to every session, about $0.2338 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.