lightroom-mcp: Instructions file for Claude Code

CLAUDE.md

lightroom-mcp CLAUDE.md is an instructions file for Claude Code from Automaat/lightroom-mcp. It costs 1,368 tokens per session, scanned A, original, MIT.

Instructions for a TypeScript server that connects Claude to Adobe Lightroom Classic through a Lightroom plugin. The setup uses two local network connections to send requests and receive responses.

In plain words
What is it for?
Use it when changing the server or plugin, investigating message transport, testing socket communication, or handling reconnect behavior.
Why use it?
It documents the connection design and important transport details needed to modify or troubleshoot this bridge safely.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md.

This is Automaat/lightroom-mcp's own configuration. It tells Claude Code how to work on lightroom-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything lightroom-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Automaat/lightroom-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.

Copy the file
curl -O https://raw.githubusercontent.com/Automaat/lightroom-mcp/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/Automaat/lightroom-mcp

Made for: Claude Code.

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Per session 1,368 This file is loaded in full into every session.
When invoked 1,368 The same file — it is already loaded in full.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.01368 $0.01368
Opus 5 $0.00684 $0.00684
Sonnet 5 $0.00274 $0.00274
Haiku 4.5 $0.00137 $0.00137

Measured 9d ago against content hash 1b78980a6ef0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

lightroom-mcp 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 9d 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 · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Lightroom MCP

MCP server bridging Claude to Adobe Lightroom Classic.

Layout

  • server/ — TypeScript MCP server (ESM, NodeNext). Stdio transport for Claude + raw TCP client to plugin sockets.
  • plugin/LightroomMCP.lrplugin/ — Lua plugin loaded by Lightroom Classic.
  • manual-test.mjs — direct TCP probe (bypasses MCP) for validating plugin dispatch.

Architecture (read before changing transport)

Plugin opens two LrSocket binds as servers; MCP server connects to both.

  • Plugin :58763 (default) in mode='receive' — server writes line-delimited JSON requests
  • Plugin :58764 (default) in mode='send' — server reads line-delimited JSON responses
  • Frame: \n terminator on every message (LrSocket buffers until newline)
  • Plugin allows one client per port at a time. MCP server holds a persistent connection.
  • LrSocket.bind in mode='receive' has a 10s no-client timeout that fires onError. Plugin auto-calls :reconnect() from a monitor loop in response. Reconnect storms are prevented by setting flags in callbacks and acting on them in the loop (never :reconnect() synchronously from onError).
  • onMessage runs in non-yielding context — handler dispatch must be wrapped in LrTasks.startAsyncTask so catalog:withReadAccessDo can yield.
  • Catalog queries that yield (getTargetPhotos, findPhotos) must run outside withReadAccessDo. Nesting a yielding query inside the read gate deadlocks on Windows: the task yields to the UI thread holding the gate, never returns, never releases it, wedging the bridge until the server timeout (#124/#134). Only non-yielding per-photo metadata reads belong inside the gate. getAllPhotos is a non-yielding enumeration, safe either side. Specs guard this via getQueriedInsideReadAccess() in spec_helper.

Pattern verified against MIDI2LR (rsjaffe/MIDI2LR, see src/plugin/Client.lua) — same dual-port LrSocket model, ports 58763/58764 also chosen there.

Commands

Use mise tasks from repo root:

  • mise run install — npm ci in server/
  • mise run buildtsc (outputs server/dist/)
  • mise run test — Jest (ESM via ts-jest)
  • mise run devtsc --watch
  • mise run lua:lintselene plugin/LightroomMCP.lrplugin
  • mise run lua:testbusted specs for the plugin
  • mise run skill:test — Python unittest for bundled skill scripts

Read the full file on GitHub · 77 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. 9d ago First seen · 77 lines · 1,368 tokens per session scan A 1b78980a6ef0

Subscribe to this mod's changes

lightroom-mcp CLAUDE.md is an instructions file published in the GitHub repository Automaat/lightroom-mcp (78 stars, last pushed yesterday), licensed MIT. It adds 1,368 tokens to every session, about $0.0068 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.

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