You can watermark a folder of documents with one prompt: an AI agent lists the files, calls the watermark tool once per file, and reports what it produced, all locally with no uploads. In Claude Desktop, Claude Code, Cursor or Windsurf the request reads:

Add a diagonal DRAFT watermark to every PDF in my documents folder, then list the files you produced.

The step-by-step version with config and troubleshooting is in the documentation: How to batch-watermark a folder of documents with an AI agent.

Why stamp by lifecycle stage instead of once?

A proposal pack is rarely marked once. It starts as DRAFT, becomes FOR REVIEW when it goes to a colleague, and loses its mark when it is approved. Doing that by hand across thirty files is the kind of work skipped under a deadline. With GroupDocs.Watermark.Mcp each stage is one sentence, and the agent supplies the loop that you would otherwise write as a script. The engine handles the format, so the same prompt covers PDF, Word, Excel, PowerPoint and image files in one folder.

Stage 1: How do you add a draft watermark to all files?

Point GROUPDOCS_MCP_STORAGE_PATH at the folder. Files are resolved by name, so the agent passes proposal-01.pdf, not a path from your machine. Then:

Add a diagonal DRAFT watermark to every PDF in my documents folder, then list the files you produced.

The agent calls add_watermark per file. Each call saves a new watermarked copy and leaves the original in place, so the source folder stays your record of the unmarked versions.

Stage 2: How do you switch to a review stamp?

After Stage 1 every file carries DRAFT, so swap the mark: remove the old one by text, then stamp the result.

Remove the DRAFT watermark from every file in this folder, then add a FOR REVIEW watermark to each result.

The agent calls remove_watermarks with textFilter set to DRAFT, then add_watermark on each cleaned copy. For a folder in mixed state, where some files are marked and some are not, tell the agent to look first:

Mark every file FOR REVIEW except the ones that already have a watermark.

It runs search_watermarks on each file and skips those that return a mark. For a different mark per format, say so:

Put the logo on the slide decks and a text mark on the PDFs.

Stage 3: How do you clear the marks when work is approved?

Approval flips the requirement. On the same folder, with your own documents:

Remove the DRAFT watermark from every file in this folder and keep the rest of the marks.

That is remove_watermarks with a textFilter of “DRAFT”. The filter is a case-insensitive substring match; without it, every watermark the engine can identify is removed. Results are saved as <name>_unwatermarked.<ext>. The details are in the companion post on searching before removing, linked below.

Example session (abridged)

You:    Add a diagonal DRAFT watermark to every PDF in my documents
        folder, then list the files you produced.
Agent:  [add_watermark x 3: text "DRAFT", rotation -45]
        Added text watermark "DRAFT" to "proposal-01.pdf"
        Added text watermark "DRAFT" to "proposal-02.pdf"
        Added text watermark "DRAFT" to "proposal-03.pdf"
        Produced 3 watermarked copies. 0 failures.
        Originals are unchanged.

What about the originals and the output folder?

By default, input and output share one folder, so watermarked copies sit beside their sources. If you prefer a clean split, set GROUPDOCS_MCP_OUTPUT_PATH to a separate folder and ship from there. Either way the originals are never overwritten, so you can re-run a stage after a source file changes; name the files you want processed again.

How do you keep a batch honest?

  • Ask for the list of produced files. A run that reports only “done” leaves you guessing which copies to ship.
  • Ask for failures explicitly. A mixed folder may include a format the engine cannot watermark. The call fails with a message instead of skipping silently, so request a list of failures.
  • Mind metered usage. Under metered licensing each file is billed as processing.
  • Check the license first. A batch in evaluation mode is a wasted run.

What are the limits?

Evaluation mode is the main one: the server’s licensing page says unlicensed output carries evaluation limitations; the exact limits are on the library’s licensing page. A folder of evaluation-mode copies is a folder of drafts you cannot distribute. Ask the agent to call get_license_status before the run; it reports mode as evaluation, licensed or metered. There is also no built-in scheduler: the server acts when your agent asks, so a recurring job needs a client or a task runner that sends the prompt.

FAQ

Can AI watermark multiple PDFs at once? Yes. The agent iterates the folder and calls add_watermark once per file, then lists the copies it produced. Each file is processed separately.

Can I add CONFIDENTIAL to every document in a folder? Yes. Replace DRAFT with CONFIDENTIAL in the prompt. Spell out whether files that already carry a mark should be skipped.

Is bulk watermarking possible locally, without uploading? Yes. The server is a local process started by your client, and it reads and writes the folder you configured.

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