Image Label MCP server

An MCP server for Image Label, a free image annotation tool. It lets Claude and other AI assistants list and upload your images, add or clean up annotations, and export COCO or YOLO training data. A LangGraph agent is included.

Use cases and setup guide: https://labels.sachin-kale.com/mcp

LangGraph agent (label-image-agent)      Claude Desktop / Claude Code / any MCP client
              │  langchain-mcp-adapters             │
              └──────────────┬──────────────────────┘
                             ▼
                    label-image-mcp (stdio or HTTP)
                             │
                             ▼
                 Image Label API  (/api/images ...)

Account

Uploading and saving annotations needs an Image Label account (request one). Without one, the tools can read but not save. Only images saved to your account are visible. Work kept only in your browser is not.

Install

Claude Desktop: download label-image-mcp.mcpb from the latest release, open it, and enter your username and password when asked.

Claude Code:

claude mcp add label-image -e LABEL_USERNAME=... -e LABEL_PASSWORD=... -- uvx label-image-mcp

Any MCP client (needs uv):

{
  "mcpServers": {
    "label-image": {
      "command": "uvx",
      "args": ["label-image-mcp"],
      "env": { "LABEL_USERNAME": "...", "LABEL_PASSWORD": "..." }
    }
  }
}

Configuration

Variable	Default	Purpose
LABEL_USERNAME / LABEL_PASSWORD	unset	Account credentials. Without them requests are anonymous and read-only in practice
LABEL_API_URL	https://labels.sachin-kale.com/api	API base URL, for another deployment or sam local start-api

Tools

Tool	What it does
list_images(category?)	Image summaries with annotation counts
get_image(image_id)	Metadata, annotations and a signed viewing URL
update_image_metadata(image_id, name?, category?, sub_category?, description?)	Edit image details
add_annotations(image_id, annotations)	Append pins, polygons, circles, rectangles or arrows
replace_annotations(image_id, annotations)	Replace all annotations
remove_annotations(image_id, annotation_ids)	Remove annotations by id
upload_image(path, name?, category?, description?)	Upload a local image file
export_annotations(image_id, format)	COCO JSON or YOLO, same output as the web app's export

There is deliberately no tool for deleting images.

HTTP mode

label-image-mcp --http [--host 127.0.0.1] [--port 8765] serves Streamable HTTP at http://HOST:PORT/mcp, so several clients can share one running server:

claude mcp add --transport http label-image http://127.0.0.1:8765/mcp

LangGraph agent

A terminal chat agent that uses these tools. The graph is START → agent ⇄ tools, with conversation memory kept for the session.

uv tool install "label-image-mcp[agent]"
export ANTHROPIC_API_KEY=... LABEL_USERNAME=... LABEL_PASSWORD=...
label-image-agent

Variable	Default	Purpose
LABEL_AGENT_MODEL	anthropic:claude-sonnet-5-5	Model as provider:model, e.g. openai:gpt-4.1 or ollama:llama3.1 (install langchain-openai / langchain-ollama)
LABEL_MCP_URL	unset	Connect to a running HTTP server instead of starting one

Development

uv sync --extra agent
uv run pytest
npx @modelcontextprotocol/inspector uv run label-image-mcp

In the Image Label app repo, ./start.sh runs this server in HTTP mode next to the web app. It reads credentials from mcp-server/.env. Releases are described in PUBLISHING.md.

License

MIT