Send a reviewed, unchanged iCloud draft after verifying its hash and explicit user intent; do not retry if send status is uncertain.
Send a reviewed, unchanged iCloud draft. Requires explicit user intent to send and hash from mail_read. Never retry an uncertain send.
| Name | Required | Description | Default |
|---|---|---|---|
| arguments | Yes |
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the annotations (readOnlyHint=false, openWorldHint=true, destructiveHint=false), it discloses the consent requirement, that the message integrity hash must originate from mail_read, and that retries after an uncertain send are forbidden. The non-idempotency warning is critical and is not derivable from the annotations or schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three short sentences, front-loaded with the action and then the two binding constraints. No filler or restatement.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For an irreversible send with no output schema, the description covers consent, integrity verification, and retry safety adequately. It stops short of describing failure/error behavior or what a successful send returns, which would round it out.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description must carry parameter meaning; it partially does by explaining that expected_sha256 comes from mail_read, but message_id is never explained. The hash origin is useful added semantics, though half the parameters remain undocumented.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb+resource ('Send a ... draft') with a meaningful constraint ('reviewed, unchanged') that separates it from mail_draft and mail_read. It does not name a sibling tool explicitly, so an agent infers the routing rather than being told it.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Gives prerequisites ('Requires explicit user intent to send and hash from mail_read') and an explicit prohibition ('Never retry an uncertain send'), which is exactly the when-not guidance an agent needs for an irreversible action.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.