Fastmail Tools

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

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.

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

List attachments for an email. Returns attachment metadata including blob_id/name/type/size. Use fastmail_download_attachment_to_s3 to fetch a specifi...

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.

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 fastm...

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

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

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 a...

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...

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

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

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

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

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

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.

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

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 fas...

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; ot...

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

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 norma...

List Fastmail Masked Email addresses via the Fastmail JMAP masked email extension (MaskedEmail/get). Returns all masked emails (ids=null) with metadat...