apple-mail-mcp

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update_message

Change read state, flag, and move multiple Apple Mail messages in a single atomic operation. Specify only fields to update.

Instructions

Update one or more messages: change read state, flag, and/or move, in one atomic call (#135).

Patch semantics — caller specifies only the fields to change. All specified mutations apply in a single AppleScript pass via the bulk-update helper. Replaces the previous mark_as_read, move_messages, and flag_message tools.

Order of operations (matters for IMAP): read-state and flag changes apply first (in source mailbox), then the move. IMAP requires the message to exist in the source folder for STORE before MOVE.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "message_ids": "<message_ids>"
    },
    "name": "update_message"
  }
}

Input Schema

Name	Required	Description
`account`	No	Account name or UUID hosting the destination mailbox. Required when `destination_mailbox` is set; also used with `source_mailbox` for narrow-path optimization.
`flagged`	No	True to flag (default red if no `flag_color` set), False to clear the flag, None to leave unchanged.
`flag_color`	No	Color name (orange, red, yellow, blue, green, purple, gray, none). Implies `flagged=True` unless "none". Validated against the existing flag-color schema.
`gmail_mode`	No	Use Gmail-specific copy+delete instead of MOVE.
`message_ids`	Yes	List of message IDs to update.
`read_status`	No	True to mark as read, False to mark as unread, None to leave unchanged.
`source_mailbox`	No	Source mailbox name. With `account`, narrows the AppleScript scan to one mailbox (O(N) instead of cross-scan).
`destination_mailbox`	No	Move messages here (requires `account`).

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.8.1Aug 24, 2026

TDQS

A4.5/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full responsibility for behavioral disclosure. It reveals atomic execution, the bulk-update helper, the IMAP ordering constraint, and even mentions a 'narrow-path optimization' with source_mailbox. It does not mention idempotency or error handling, but the atomicity and ordering are well covered.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is compact and front-loaded: the main purpose is stated in the first sentence, then the patch semantics and order of operations follow in clear, short paragraphs. There is no filler; every sentence adds necessary context for correct invocation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (8 parameters, atomic batch update, IMAP constraints, and replacement of three prior tools), the description covers all critical aspects: what it does, when to use it, how it behaves atomically, and the order of operations. An output schema exists, so return values are not the description's responsibility. No essential information for an agent to call the tool correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema already provides 100% coverage, describing each parameter and their interplay (e.g., 'flag_color implies flagged=True unless none'). The description adds patch semantics as a general principle, but does not enrich individual parameter meaning beyond the schema. The baseline of 3 is appropriate because the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description starts with a precise verb-resource pairing: 'Update one or more messages: change read state, flag, and/or move, in one atomic call.' It enumerates the exact operations and states it is atomic. It also explicitly distinguishes itself from prior separate tools by naming them and saying it replaces them.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit when-to-use guidance: it lists the three legacy tools it replaces, so an agent knows to prefer this consolidated tool. It also explains patch semantics ('caller specifies only the fields to change') and gives operational order ('read-state and flag changes apply first, then the move'), which is essential for correct IMAP usage.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.