How to prepare physical mail from Claude and Cowork

Claude can help you get the wording right. Postedly handles the next part: preparing a fax or mailing the letter. Bring the finished file and the recipient; review everything before it goes.

See the setup guide See example requests

Tested through quote and review link

Last tested

Claude’s web connector has transferred a runtime-created PDF, received an unpaid fax quote and returned a private review link. A complete paid send and a separate Cowork run have not been verified.

Client and environment
Claude web custom connector to Postedly production. Cowork is a documented setup path, not a separately tested client.
Stages completed
OAuth; service and product lookup; runtime PDF upload with matching checksum; unpaid fax quote; private review link. Zero orders created.
Your remaining steps
Make the final PDF accessible, approve the required tool calls, open the review link and inspect its proof and recipient. Approve your order and complete hosted Stripe Checkout only when ready.
Still unverified
Visual proof review in this Claude run; completed fallback upload; real-order lookup; payment; fulfillment; refresh/disconnect; a public listing and the Cowork workflow.

Use Claude & Cowork with Postedly

  1. Add Postedly in Claude

    Open Customize → Connectors → Add custom connector. Enter Postedly as the name and this URL, then choose Continue. In managed workspaces, an owner may need to add it first.

    https://postedly.com/mcp/send

  2. Connect your sender account

    Choose Sign in now and Register automatically (DCR), then Add. Complete Postedly’s email verification and OAuth consent, then enable the connector in your conversation.

  3. Give Claude the finished file

    Attach the approved PDF or connect the folder containing it. Ask Claude to confirm the filename and read the actual file bytes. For mail, provide full recipient and sender addresses; for fax, provide the US receiving number.

  4. Check the quote and open the proof

    Ask for one quote, then open Postedly’s private review link yourself. Check the final pages, destination, selected service and full total before approving payment.

A real Claude preparation test

On September 20, 2026 (UTC), Claude web created a one-page synthetic PDF, read its saved bytes and uploaded it with a matching checksum. Postedly returned an unpaid fax quote and a private browser review link. The quote included a two-page final document with the fax cover. The link was not opened, and orders were empty before and after. This test proves preparation through the review link; it does not establish a mailed letter, a Cowork run or a paid send.

Give it a specific request

Mail the final letter from a working folder

Name the approved version so Cowork does not choose an older draft. This example is a suggested request, not a separately verified Cowork run.

Example request
Use the final welcome letter in the folder I connected. Confirm the filename, export that version as a PDF, and use Postedly to prepare mailing one copy to the recipient address below. Use my sender address below, show the final proof and total, and stop before payment.

Fax the PDF Claude just created

The recorded Claude test reached an unpaid fax quote and private review link using a PDF created in its runtime.

Example request
Use Postedly to prepare a fax of this finished PDF to the US fax number below. Transfer the actual saved file, check the recipient details, and give me the private link to review every page including the cover. Do not pay or send yet.

Send a personal postcard

Prepare the message and artwork together, then check the selected postcard template.

Example request
Help me finish this postcard for my parents, check Postedly’s artwork requirements, and prepare a quote. Show both sides and the total before checkout.

Transfer your file

A connector does not automatically receive your files. When Claude can read the actual bytes, it can use the upload tool or a private multipart handoff. If that access is unavailable, use the browser upload link. A local path alone is not an upload.

  • For a letter or fax, prepare a valid, unencrypted PDF no larger than 10 MiB (10,485,760 bytes). Review the saved PDF after exporting it from the draft.
  • For mail, have the recipient’s full US postal address and your US sender address ready. For fax, confirm the receiving US fax number and your US billing address. Check the selected service’s page and layout limits before quoting.
  • Review the final proof returned with the quote, including any added cover or postal layout. An upload preview alone does not establish that the final document is ready to send.
Letter requirements Fax requirements

Mail a check

Claude & Cowork can prepare a paper check drawn on your own verified US checking account. The assistant never sees your account numbers and can’t sign or pay; those steps stay with you.

  1. Set up checks once, yourself

    Open Postedly’s check page in your browser, verify your email and connect your checking account. You’ll verify it with Plaid, confirm you can sign for it, set a bank passkey and save your signature.

    Set up checks

  2. Ask Claude & Cowork for the check

    Give the payee’s exact name and US mailing address, the amount and an optional memo. Using Postedly’s check tools, Claude & Cowork reads your ready accounts and drafts the check, which reserves its number and prepares a service-fee quote. Nothing is signed, charged or sent.

  3. Review, sign and pay

    Open the private review link it gives you. Check the full proof, confirm with your passkey, sign and pay the service fee. The check amount is paid from your account only when the payee deposits it.

  4. Follow the order

    Claude & Cowork can read the order to see when the check is printed and mailed. Postedly can’t see when it clears; your bank shows that.

Example request
Mail a $250 check to Riverside Little League, 400 Park Rd, Dayton, OH 45402, from my checking account. Memo: Spring registration. Send me the link to review and sign it.

If Claude & Cowork doesn’t show Postedly’s check tools, reconnect Postedly or refresh its tools, or write the check yourself on Postedly.

When a step does not work

Postedly is connected but its tools are missing
Enable Postedly in the current conversation’s connector controls. If the tool list is stale, refresh the connector’s tools and start a new conversation. Workspace owners may need to add the connector before members can connect.
Cowork cannot reach the finished file
Confirm the final PDF is in a folder you have connected and that the desktop app is available when local file access is needed. Ask Claude to identify the exact file it will transfer. If it cannot read the bytes, use the private browser upload link.
Claude asks for tool approval
Review and approve the specific preparation call. The recorded test used approval for each invocation; you do not need to enable persistent permission to prepare a quote. Tool approval is separate from approving an order on Postedly.

Your approval comes before the send

Postedly prepares a quote tied to the final document and recipient. You review that proof and the total in the browser before continuing to Stripe Checkout. Connecting Claude grants no blanket permission to buy or send.

Cancellation and refund policy

Follow the existing order

Keep the returned order reference and ask Claude to check it. A payment confirmation and a delivered letter are different milestones.

Check an order on Postedly

Send directly on Postedly

You can use the finished document without connecting an assistant. Download the approved PDF, open Postedly, choose an available service and upload the file. Enter the destination and sender details, then review the final proof and full price before payment. You do not need your own printer or envelopes to mail a PDF through Postedly.

Open the sending form Follow a sending guide Check services and pricing

Before you start

  • Connector availability depends on your Claude account and workspace settings. Cowork can use only files you make accessible. Postedly accepts files up to 10 MiB; postcard artwork must match the selected postcard template. Native Claude payment is not claimed.

Official references

Use these platform references alongside the Postedly guide.

Ready to prepare a send?

Use the connected assistant, or finish directly with Postedly.

Start sending