Read email attachments with AI: PDF, Word and images, and what is not supported

Short answer: an AI assistant can read an email attachment only if the connector exposes it. With Fezola, PDF, Word, text, HTML, CSV and similar files are returned as text, up to 50,000 characters, and images (PNG, JPEG, GIF, WebP) come back as images. Scanned PDFs without text, spreadsheets and archives are reported as unsupported, never guessed, and files over 10 MB are not read. The built-in Gmail connector of Claude gives attachment metadata only, according to Anthropic's help article (checked 9 November 2026).

Why attachments matter

The important facts of an email are often not in its body. The amount is on the PDF invoice, the notice period in the signed contract, the time in the boarding pass. If the assistant cannot open the attachment, it can tell you that an invoice arrived, but not what it says.

What can be read, exactly

Verified in Fezola's code (the get_attachment tool):

Kind	What the assistant gets
PDF with text	The text, up to 50,000 characters
Word (.docx), text, HTML, CSV, JSON, calendar files	The text, up to 50,000 characters
Images: PNG, JPEG, GIF, WebP	The image itself, up to 3.5 MB
Spreadsheets, archives	Reported as unsupported
Scanned PDFs without text	Reported as unsupported
Anything over 10 MB	Not read

When a document is long, the result carries truncated: true, so the assistant knows it only saw the beginning. It never makes up what it could not read.

How it works

1. get_message lists the attachments of an email: name, type, size.
2. get_attachment reads one by its position (index 0 is the first).
3. The assistant answers from the text, or looks at the image.

Neither tool marks the email as read.

Three examples

"Open the PDF invoice from the hosting provider and tell me the total and the due date."

An invoice: Claude reads the text and returns the amount and date, which you can paste into your accounting.

"In the signed contract with Acme, what are the payment terms and the notice period?"

A contract: Claude reads the document and quotes the clauses. For a very long contract, ask for the section you need, because the text is truncated beyond 50,000 characters.

"What time is my train in the ticket I received yesterday?"

A ticket or a photo: an image attachment is returned as an image that the assistant can look at.

The other direction: drafts with attachments

A draft can carry an attachment taken from another email, or a file the assistant writes. For example: "Reply to the accountant and attach the invoice from this morning." The draft is saved in the mailbox for you to review, and nothing is sent unless you switch on direct sending for that mailbox.

Honest limits

• Scanned documents. A scan without a text layer cannot be read: say so to the assistant and open it yourself.
• Spreadsheets. Excel files are not read. Export the table to CSV or paste it into the email.
• Length and size. Text beyond 50,000 characters is truncated, files over 10 MB are not read, images over 3.5 MB are not shown.
• Untrusted content. An attachment can contain instructions aimed at the model. Read what the assistant proposes before you act: see is it safe to give an AI access to your email?.

Try it

Create a free Fezola account, add a mailbox, add Fezola to Claude with https://api.fezola.com/mcp (how to add a custom connector to Claude) and ask about an invoice. In ChatGPT, custom MCP servers are available on Business and Enterprise/Edu plans (Pro read-only): how to add an MCP server to ChatGPT.

For searching across mailboxes first, see search all your email accounts at once with Claude. To compare connectors, best email MCP servers, and for the basics, what is an email MCP server.