All Providers/Email Services/Fastmail

Fastmail

Fastmail is an email provider with a modern standards-based API via JMAP. These tools let you list mailboxes, search and fetch emails, triage messages (read/unread, move), send email via JMAP submission, and manage Fastmail Masked Email addresses.

This Fastmail MCP server is compatible with any MCP client including Claude Desktop, Cursor, and other Model Context Protocol implementations.

Email Services

FIELDS

Official Website

Tools From This Provider (22)

Fastmail Create Draft

Create a draft email in Fastmail. This uploads an RFC822 message and imports it into the Drafts mailbox. Returns the created draft email id. Use fastmail_fetch_email to read it or...

Fastmail Delete Draft

Delete a Fastmail draft by destroying the underlying Email object via JMAP Email/set destroy. This permanently removes the draft.

Fastmail List Drafts

List email drafts in Fastmail (messages stored in the Drafts mailbox). Returns draft email ids; use fastmail_fetch_email to read a draft body, and fastmail_delete_draft to remove it.

Fastmail Reply Email

Reply to an email in Fastmail using JMAP. Supports reply-all and HTML bodies. This preserves threading by setting inReplyTo and references.

Fastmail Send Email

Send an email from Fastmail using JMAP. Supports multiple recipients, CC/BCC, Reply-To, and HTML bodies. For replies in an existing conversation, use fastmail_reply_email.

Fastmail Fetch Thread

Fetch a thread by id via JMAP Thread/get. Returns thread metadata including the emailIds in the thread. Use fastmail_get_thread_content to fetch normalized message bodies for the whole thread.

Fastmail Get Thread Content

Fetch a Fastmail thread and return normalized content for each message (headers + body_text). This is the best tool for reviewing an entire conversation at once.

Fastmail Create Masked Email

Create a new Fastmail Masked Email address via MaskedEmail/set. Returns the created masked email object (including the generated email address).

Fastmail List Masked Emails

List Fastmail Masked Email addresses via the Fastmail JMAP masked email extension (MaskedEmail/get). Returns all masked emails (ids=null) with metadata like state, forDomain, description, createdAt,...

Fastmail Update Masked Email

Update an existing Fastmail Masked Email via MaskedEmail/set. Supports changing state (enabled/disabled/deleted) and metadata fields (forDomain, description, url).

Fastmail Validate Token

Validate the Fastmail API token by fetching the JMAP session and checking capabilities. Returns 'ok' when mail + submission capabilities are present; otherwise returns missing capabilities.

Fastmail Fetch Email

Fetch an email by id via JMAP Email/get and return normalized fields (from/to/subject/dates + body_text). Use include_html=true when you need HTML; otherwise returns plain text best-effort.

Fastmail List Mailboxes

List mailboxes (folders) in Fastmail via JMAP Mailbox/get. Results include id, name, role (e.g. inbox, trash), and other metadata. Use mailbox ids from this tool with fastmail_search_emails and...

Fastmail Mark Read Unread

Mark an email as read/unread in Fastmail via JMAP Email/set by toggling the $seen keyword. Use this for inbox triage.

Fastmail Move Email

Move an email to a target mailbox by setting mailboxIds via JMAP Email/set. This is the building block for archive/trash workflows (move to archive or trash mailbox).

Fastmail Search Emails

Search Fastmail emails via JMAP Email/query. Returns matching email ids plus query metadata (queryState, total, canCalculateChanges). Use returned ids with fastmail_fetch_email.

Fastmail Archive Email

Archive an email in Fastmail. This removes the message from the Inbox mailbox and adds it to the Archive mailbox (by mailbox role), while preserving any other mailbox membership.

Fastmail Batch Mark Read Unread

Mark multiple emails read/unread using one JMAP Email/set call by toggling the $seen keyword on each id. Use this to triage many messages quickly.

Fastmail Batch Move Emails

Move multiple emails into a mailbox using a single JMAP Email/set call. This REPLACES mailboxIds for each email with only the target mailbox id.

Fastmail Trash Email

Move an email to Trash in Fastmail by setting mailboxIds to the Trash mailbox (role=trash). Use this for delete workflows.

Fastmail Get Attachment Download Url

Get a short-lived download URL for a Fastmail attachment. The returned URL expires; call this tool again to generate a fresh URL if needed.

Fastmail List Email Attachments

List attachments for an email. Returns attachment metadata including blob_id/name/type/size. Use fastmail_download_attachment_to_s3 to fetch a specific attachment to S3 and get a presigned URL.

Related Bundles (1)

Fastmail Tools

Fastmail is an email provider with a modern standards-based API via JMAP. These tools let you list mailboxes, search and fetch emails, triage messages (read/unread, move), send email via JMAP...

Provider Information

CategoryEmail Services

Auth TypeFIELDS

AddedDecember 27, 2025

UpdatedFebruary 1, 2026

Used By Tools

22

Quick Links

Official Website

Need Help?

Having trouble configuring Fastmail? Check the available resources below.

Browse Other Providers

Fastmail MCP Server - MCP Bundles • MCP Providers