PostageCan Claude Read Email Attachments?
Checked November 6, 2026
Yes, if its email connection hands over the file's contents. Through Postage, Claude can read the text of PDF, plain text, HTML, CSV, JSON and XML attachments in any of your IMAP accounts. For images, Word files, spreadsheets and other formats, it gets the file's name, type and size but can't read what's inside.
Which files Claude can read
| Attachment | What Claude gets |
|---|---|
| PDF with selectable text | The text |
| Plain text, CSV, JSON, XML | The text |
| HTML | The text, without the markup |
| Scanned PDF with no text layer | Name, type and size. There's no text to read |
| Images | Name, type and size |
| Word, Excel and other Office files | Name, type and size |
Postage returns up to the first 100,000 characters of a file. The text reaches Claude marked as untrusted, the same as an email body.
How to ask
- Connect Claude Desktop or Claude Code in Postage's Settings > Agents (setup steps). Read only is enough.
- Ask for the file by what you remember: "Find the PDF contract Dana sent in August and tell me when it ends."
Claude searches with hasAttachment, lists the message's files with list_attachments, and reads one with get_attachment_text. Postage downloads the file from your mail provider to your Mac to read it. Your mail doesn't pass through a Postage server.
Things to ask
- "Pull the totals from the invoices my accountant sent this quarter."
- "Read the CSV Sam attached and tell me which rows are missing a date."
- "Compare the two lease PDFs from my landlord and list what changed."
- "Which of last month's receipts came as PDFs? List the vendor and amount for each."
Treat what an attachment says the way you'd treat a stranger's email. A PDF can hold text aimed at an AI, which is why Postage marks it as untrusted and agents can't send mail on their own. More in Is it safe to give an AI agent your email?
Questions
Can Claude attach a file to an email?
Not through Postage. Its compose tools have no attachment option. Claude writes the message, and you add the file in the compose window before you press Send.
Can Claude save an attachment to my Mac?
Not through Postage's tools. Save it from the message in Postage.
Does this work with Codex and other agents?
Yes. Postage gives the same attachment tools to every agent you connect, including Codex and Cursor.
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