PDFKing for AI assistants

Connecting

1. 1.Add this address in your assistant's connector or MCP server settings:https://pdfking.app/api/api/connector/v1/mcp
2. 2. Your assistant sends you to PDFKing to sign in and approve the connection. You approve what it may do; no key is created or shared.
3. 3. That is it. The assistant stores its own credential and refreshes it on its own.

A free PDFKing account is required. Accounts created with Google need a password set in account settings first, because the approval screen asks for one.

Sending a file

Attach the PDF to the chat as you normally would and say "Compress this PDF using PDFKing". Your assistant sends the file straight to us from its own sandbox — the document itself never passes through the conversation, so nothing is retyped and no code changes hands.

This needs one setting, once. An assistant's sandbox blocks outbound connections until you allow them, so add pdfking.app under Settings → Capabilities → Code execution → Additional allowed domains. Until you do, the transfer fails and your assistant will say it could not reach PDFKing.

If your assistant cannot run code

Some platforms have no sandbox to send from. There the file takes the other route: upload it at pdfking.app/connect-ai and say "Compress the PDF I just uploaded to PDFKing". Still nothing to copy across — the short code that page shows, like PK-7F2QX9, is only needed if you have uploaded more than one file and have to say which.

You get back a download link. Because the file never passes through the conversation, there is no size limit imposed by the chat and it costs you nothing in tokens.

What it can do

Compress PDF — reduces file size by down-sampling and re-encoding the images inside the document and rewriting its internal streams. Choose low, medium (default) or high.

Image-heavy and scanned documents typically shrink by 50–75%. A text-only PDF that is already well optimised may not shrink at all, and PDFKing says so rather than pretending otherwise. Page count, page order and text are never changed, and your original file is never modified.

More PDFKing tools will follow. Compress is the first.

What happens to your file

This matters, and it is different from using PDFKing in your browser. Most PDFKing tools run on your own device and your file never leaves it. The AI connector cannot work that way — the file has to reach our servers to be processed.

• Files are deleted within 60 minutes, automatically.
• A file is used once and stops being offered after 30 minutes, as does the code that names it.
• Nothing is shared with any third party.
• We record that an operation happened — the tool, sizes, timing — for the audit log. The contents of your document are not stored.
• Your files, quota and history are isolated to your account. A connected assistant can only reach files you sent it.

See the privacy policy for the full detail.

Permissions and disconnecting

When you approve a connection you are asked for four permissions: upload files, read the files it uploaded, see the available tools, and run them. Taking or removing document passwords is a separate permission that this connector does not request.

You can disconnect any assistant from your connect page. Access stops on its very next request, not when its token happens to expire.

Limits

• Maximum file size: 100 MB.
• 200 operations per day, per account.
• 500 MB of files held at once, per account.
• PDFs only, for now.

Troubleshooting and support

My assistant says it cannot reach PDFKing.

Its sandbox is blocking the connection, not us. Add pdfking.app to the allowed domains under Settings → Capabilities → Code execution, then ask again. If the platform cannot run code at all, upload at /connect-ai instead.

My assistant asks which file I mean.

It will only pick a file on its own when exactly one is waiting. Upload two and it has to ask rather than guess — read out the code shown under the one you want.

"No file is waiting under that code."

Codes work once and expire after 30 minutes, and they belong to the account that created them. Upload again for a fresh one.

Sign-in fails on the approval screen.

If you created your account with Google it has no password yet. Set one in account settings, then connect.

Anything else: contact us.