What the assistant can do

The Skybox MCP server offers an assistant a set of tools. A tool is one well-defined action, such as search messages or create an event. The assistant decides which tool answers your request and calls it with the details; the tool runs with your permissions, on the accounts you allowed, and returns the result into the conversation.

Three rules hold for every tool:

• Nothing happens on an account you did not allow. The account selection you made on the authorization screen (or later under Settings → Connected Apps) is checked on every call.
• The assistant must name its target. No tool picks an account, folder or calendar on its own. If you say "archive this", the assistant has to know which account and folder the message is in. It learns that from the messages it listed or searched before.
• Your mail stays at your provider. Skybox fetches what the assistant asks for from your mail server at that moment and hands it on. Nothing the assistant reads is kept on Skybox's servers beyond what the Skybox app itself caches; see Permissions, data and privacy.

An assistant usually calls several tools for one request: list the accounts, search, read a message, then act. You see each step in the assistant's interface.

Accounts

Tool	What it does
list_mail_accounts	The mail accounts the assistant may reach, with their addresses and aliases. The starting point for almost everything else.
get_quota	The storage used and available on a mail account, where the mail server reports it.
list_caldav_accounts	The calendar accounts the assistant may reach.
list_carddav_accounts	The contact accounts the assistant may reach.

Reading mail

Tool	What it does
list_messages	A page of messages from a folder of one or more accounts: sender, recipients, subject, date, flags, whether there are attachments. No message bodies.
search_messages	The same, filtered: by text, sender, recipient, subject, date range or flags, across the accounts you allow.
get_message	One message in full: headers, the text and HTML body, and the list of attachments with names and sizes. For a bounce, the parsed delivery report.
get_attachment	One attachment of one message. By default the assistant receives a download link valid for 15 minutes and fetches the file into its own workspace; a text attachment can be returned as text, an image as an image.
present_message_picker	Shows you a checklist of messages inside the chat, with a question and buttons. Your choice goes back to the assistant as your next message. Used when the assistant wants you to pick, not guess.

Writing mail

Tool	What it does
compose_email	Opens a compose window inside the chat, pre-filled with the assistant's draft. You read it, change it and press Send yourself. The assistant does not send on its own after this.
send_email	Sends a message from one of your accounts, as a new message or a reply in a thread, with attachments. Can request a read receipt or a delivery receipt.
save_draft	Saves a message to the account's Drafts folder instead of sending it.
create_upload, complete_upload, get_upload_status	How a file that is not in any mailbox yet, for example one the assistant produced, becomes an attachment: the assistant uploads it over HTTPS straight into Skybox and then refers to it. Up to 25 MB as an attachment; a larger file is sent as a download link that expires. These tools appear only on instances with file storage enabled.

An attachment on a sent message or draft is either a file the assistant uploaded, or a reference to an attachment of an existing message, which Skybox copies from your mail server directly. That is how a forward works without the file ever passing through the conversation.

Organizing mail

Moves, copies, deletions and flag changes run as background jobs: the assistant starts the job, Skybox carries it out against the mail server, and the assistant waits for the result or checks on it later. A job on hundreds of messages finishes even if the chat moves on.

Tool	What it does
move_messages	Moves messages to another folder, within an account or to another account.
copy_messages	Copies messages to another folder or account.
delete_messages	Deletes messages for good. To put something in the Trash instead, the assistant moves it to the Trash folder with move_messages.
set_message_flags	Marks messages read or unread, flagged or unflagged, and sets or clears other flags.
get_mail_job, list_mail_jobs, cancel_mail_job	Progress of a running job, the recent jobs, and stopping one.

Tool	What it does
list_mailboxes	The folder tree of an account.
create_mailbox	Creates a folder.
rename_mailbox	Renames or moves a folder.
delete_mailbox	Deletes a folder.

Calendar

Tool	What it does
list_calendars	The calendars of a calendar account.
list_events	The events in a time range, from the calendars you name or all of them.
create_event	Creates an event in a named calendar, with time, location, description, attendees and a repeat rule where the calendar supports it.
update_event	Changes an existing event.
delete_event	Deletes an event.

Contacts

Tool	What it does
list_contacts	The contacts in an address book.
search_contacts	Contacts matching a name, address or other field.
create_contact	Adds a contact.
update_contact	Changes a contact.
delete_contact	Deletes a contact.

Which tools an app gets

The authorization screen shows what the app asked for: mail, calendar, contacts, and whether it wants to read only or also write. An app that asked for mail only never sees the calendar tools. An app that later asks for more sends you through the authorization screen again. For an API key you pick the tools one by one; see Other clients and API keys.