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

Tools From This Provider (22)

Fastmail Validate Token

Validate the Fastmail API token by fetching the JMAP session and checking capabilities. Returns 'ok' when mail +...

Fastmail Trash Email

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

Fastmail Reply Email

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

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...

Fastmail Batch Move Emails

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

Fastmail Create Draft

Create a draft email in Fastmail. This uploads an RFC822 message and imports it into the Drafts mailbox. Returns the...

Fastmail Move Email

Move an email to a target mailbox by setting mailboxIds via JMAP Email/set. This is the building block for...

Fastmail Search Emails

Search Fastmail emails via JMAP Email/query. Returns matching email ids plus query metadata (queryState, total,...

Fastmail List Masked Emails

List Fastmail Masked Email addresses via the Fastmail JMAP masked email extension (MaskedEmail/get). Returns all masked...

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...

Fastmail List Drafts

List email drafts in Fastmail (messages stored in the Drafts mailbox). Returns draft email ids; use...

Fastmail Delete Draft

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

Fastmail Send Email

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

Fastmail Create Masked Email

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

Fastmail Archive Email

Archive an email in Fastmail. This removes the message from the Inbox mailbox and adds it to the Archive mailbox (by...

Fastmail List Mailboxes

List mailboxes (folders) in Fastmail via JMAP Mailbox/get. Results include id, name, role (e.g. inbox, trash), and...

Fastmail List Email Attachments

List attachments for an email. Returns attachment metadata including blob_id/name/type/size. Use...

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 Fetch Thread

Fetch a thread by id via JMAP Thread/get. Returns thread metadata including the emailIds in the thread. Use...

Fastmail Update Masked Email

Update an existing Fastmail Masked Email via MaskedEmail/set. Supports changing state (enabled/disabled/deleted) and...

Fastmail Get Thread Content

Fetch a Fastmail thread and return normalized content for each message (headers + body_text). This is the best tool for...

Fastmail Fetch Email

Fetch an email by id via JMAP Email/get and return normalized fields (from/to/subject/dates + body_text). Use...

Provider Information

CategoryEmail Services
Auth TypeFIELDS
AddedDecember 27, 2025
UpdatedFebruary 1, 2026
Used By Tools
22

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Fastmail MCP Server - MCP Bundles • MCP Providers