Borrowing it
Nothing to install: this file belongs to MALeitch/live-ketcher-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/MALeitch/live-ketcher-mcp/master/AGENTS.mdgit clone --depth 1 https://github.com/MALeitch/live-ketcher-mcpWrote 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.
[](https://agentmods.dev/instructions/maleitch/live-ketcher-mcp/agents-md)<a href="https://agentmods.dev/instructions/maleitch/live-ketcher-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/maleitch/live-ketcher-mcp/agents-md/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.
<a href="https://agentmods.dev/instructions/maleitch/live-ketcher-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/maleitch/live-ketcher-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.03063 | $0.03063 |
| Opus 5 | $0.01532 | $0.01532 |
| Sonnet 5 | $0.00613 | $0.00613 |
| Haiku 4.5 | $0.00306 | $0.00306 |
Grade A, and why
live-ketcher-mcp AGENTS.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 10d 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.
How it starts
The opening of the file, as written. The whole thing — 244 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Development notes
Read this before changing ketcher_connector/. ROADMAP.md carries the
full port scope and the prototype measurements behind these rules.
Architecture
ketcher_connector/
transport/
connection.py launch/attach a live, visible browser running Ketcher
document.py read_document/apply_transform -- the whole-document rule
identity.py stable claude-* ids via content hash, no native tags
internals.py quarantined below-API access (undo/redo/selection)
worker.py dedicated thread owning the Playwright session --
NOT optional, see rule 4 below
domain/ pure logic, zero editor imports, pytest-covered
bridge/ the seam: every tool call goes through here, async
tools/ thin MCP tool definitions, async where they touch the bridge
All four Phase 0 transport modules and the bridge/server skeleton are
written and verified live (both via direct script and via a real
mcp.call_tool round trip) as of this note. test_smoke_visual.py
exercises all of it.
Non-negotiable rules
1. Read the whole document, write the whole document
ketcher.setMolecule() replaces the entire canvas. Measured on a
3-molecule canvas: writing back only the first molecule took it from 13
atoms to 6 and silently destroyed the user's other two structures.
The transport must expose a read_document() / write_document() pair
that makes a partial write structurally impossible from the tool layer.
Never call setMolecule with a subset of root.nodes.
Recoverable via undo if it does happen, but do not rely on that.
2. Do not reach below window.ketcher.* without quarantining it
The documented API surface is the Ketcher class in
ketcher-core/src/application/ketcher.ts. Everything else
(editor.selection(), editor.historyStack, editor.historyPtr,
editor.struct(), drawingEntitiesManager) works but is unversioned and
can break across Ketcher releases.
Confine all of it to one module in transport/ so a Ketcher upgrade has a
single blast radius. editor.undo()/redo()/historySize() are needed for
the undo tools and are the main reason this exception exists at all.
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.
- 10d ago First seen · 244 lines · 3,063 tokens per session scan A d42810f1ad60
live-ketcher-mcp AGENTS.md is an instructions file published in the GitHub repository MALeitch/live-ketcher-mcp (2 stars, last pushed 1mo ago), licensed MIT. It adds 3,063 tokens to every session, about $0.0153 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 2026-08-31.
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vscode buildNext.instructions.md
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spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
langchain AGENTS.md
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