Etchv Labs MCP Server

Etchv MCP server

A local stdio Model Context Protocol server that lets AI assistants watermark and detect images, PDFs and videos with Etchv.

Requirements

• Node.js 24 or later
• An Etchv API key with only the scopes you need
• An existing directory for input and output files

Configuration

Claude Code

claude mcp add etchv --scope user \
  -e ETCHV_API_KEY="$ETCHV_API_KEY" \
  -e ETCHV_FILES_ROOT="$HOME/etchv-media" \
  -- npx -y @etchv-labs/mcp-server@1

Editor plugins

This repository is also a Cursor plugin (.cursor-plugin/plugin.json with mcp.json) and a Gemini CLI extension (gemini-extension.json). Both run the same package and need ETCHV_API_KEY and ETCHV_FILES_ROOT. Gemini CLI asks for them at install; in Cursor, set them under Plugins, then Configure:

gemini extensions install https://github.com/etchv-labs/mcp-server

Claude Desktop, Cursor and other mcpServers clients

Add this to the client's MCP config (for example claude_desktop_config.json or ~/.cursor/mcp.json) and restart it:

{
  "mcpServers": {
    "etchv": {
      "command": "npx",
      "args": ["-y", "@etchv-labs/mcp-server@1"],
      "env": {
        "ETCHV_API_KEY": "YOUR_ETCHV_API_KEY",
        "ETCHV_FILES_ROOT": "/absolute/path/to/etchv-media"
      }
    }
  }
}

Then ask the assistant to run check_api_key to confirm the connection.

Tools

Every tool has a title and readOnlyHint, destructiveHint, idempotentHint and openWorldHint annotations.

Inputs and outputs

watermark_media and detect_media take the file as exactly one of:

• input_path: a local file inside ETCHV_FILES_ROOT.
• input_url: a public HTTPS URL. The server downloads it and submits it like a local file. See Security for the checks it applies. The file name comes from the Content-Disposition header, else the URL path; pass filename to set it. Its extension must match media.
• upload_id: an upl_ ID from create_upload. A client that can send files itself calls create_upload with kind (image, document, video, or detect to check a delivered file), filename and the exact size in bytes, PUTs the bytes to the returned upload.url without an API key, then passes upload_id. An upload is used once and expires after 24 hours.
• asset_id: an existing asset, such as a delivered file to check. The server downloads it and submits it again. filename can override its name here too.

A watermarked file is saved to output_path when one is given (sync watermark_media, get_job_result and download_asset). Without output_path, these tools return the result's asset_id and metadata with download_url and download_expires_at: a link that works without an API key for 15 minutes. Anyone with the link can download the file, so share it only with the person who needs it. Creating a link needs the assets:read scope; if it fails, the error names the asset so you can call download_asset once the key allows it.

Submissions require a stable idempotency_key; reuse it when retrying so you are not charged twice. Image and PDF uploads are limited to 50 MiB and DOCX, PPTX and video uploads to 20 MiB. A PDF has 1 to 2,000 pages, and its watermarked copy must fit in 95 MiB with 48 KiB per page, so a 2,000-page PDF can be up to about 1 MiB. Detection takes the files Etchv delivered: up to 192 MiB for images, 95 MiB for PDFs and 100 MiB for DOCX, PPTX and video. Files over 40 MiB go through an upload session automatically, and image or document detection above 95 MiB returns a job receipt to collect with get_job_result. Storage destinations and webhook endpoints are created in the dashboard, not through this server.

watermark_media and detect_media accept an optional accelerator (cpu, the default, or gpu). GPU processing requires a Business or Enterprise plan and costs 3× credits; if no GPU is ready, the job runs on CPU at normal credits. Results report the hardware actually used as accelerator, and get_job also returns accelerator_requested. watermark_media and watermark_batch also accept active_content for PDFs: keep (the default) returns scripts and actions as uploaded, and remove_auto_run removes what a PDF viewer runs by itself, such as open actions, document-level JavaScript and XFA forms. In a batch, remove_auto_run needs every file to be a PDF. When a rate or concurrency limit is reached, errors include retry_after_seconds and point to the plan upgrade page. Trial and Launch plans run one operation at a time.

Batches

watermark_batch takes up to 100 files, named one of three ways: input_paths, input_dir with an optional glob (for example "contracts/*.pdf"; braces and .. are refused), or items with their own data. A data_template fills in each file's data; string values may use {filename}, {stem} and {index} (the file's 0-based position). The server creates the batch, uploads each file once to its signed URL without the API key, and starts it. With wait: true it polls at the pace the API asks for, for up to wait_seconds (default 600), sending progress notifications when the client asks for them, and with output_dir saves the results. Otherwise call get_batch, then download_batch, which saves each successful file under its name in the batch zip (NNN-<name>-watermarked.<ext>), or the single zip when the batch was created with archive: true, and lists failed items with their error codes. Each file costs the same credits as a single request, and files that fail are refunded. Retrying with the same arguments resumes or returns the same batch; if that batch expired unstarted or its results have expired, the tool asks for a new idempotency_key.

Hosted mode

The etchv-mcp command always runs in local mode. createServer in src/server.ts also takes mode: "hosted" for a server that runs remotely and has no access to the user's files. In hosted mode no filesRoot is needed; input_path, output_path and the other local file arguments are left out of every tool schema; watermark_batch and download_batch are not offered; results are returned as download links; and the server instructions and etchv://capabilities describe that mode.

Security

• The API key is read only from ETCHV_API_KEY, sent only to the configured origin, and never appears in tool arguments, results, errors or logs.
• File access is confined to ETCHV_FILES_ROOT: traversal and symlinks are rejected, and existing files are never overwritten.
• Only HTTPS API origins are accepted (HTTP for localhost only), and API redirects are never followed.
• input_url must be HTTPS without a user name or password. The host must resolve only to public addresses: loopback, private, link-local, carrier-grade NAT, multicast, reserved and documentation ranges are refused, including IPv6 forms that embed such an IPv4 address. The connection uses the checked address, at most 3 redirects are followed and each is checked again, the download is capped at the operation's upload limit and times out, and the API key is never sent to the URL.
• API responses, asset names and metadata are treated as untrusted data, never instructions.

Links

• Guide: https://etchv.com/docs/mcp?utm_source=mcp-local&utm_medium=readme&utm_campaign=integrations
• API reference: https://etchv.com/docs?utm_source=mcp-local&utm_medium=readme&utm_campaign=integrations
• Issues: https://github.com/etchv-labs/mcp-server/issues
• Support: hello@etchv.com

Questions or bug reports: open an issue here or email hello@etchv.com.

License

MIT