apple_mail_send

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

The description adds behavioral context beyond annotations by stating that sending is immediate ('immediately sends email') and that it comes from a selected local account. This is useful because annotations only indicate it's a write operation (readOnlyHint=false) without specifying timing or source selection. However, it does not disclose irreversibility or potential error conditions.

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?

The description is concise, front-loaded with the core action, and every sentence adds value. It is two sentences long with no redundant content, making it easy to parse quickly.

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 a tool with 6 parameters and no output schema, the description is too brief. It states the immediate send behavior but does not explain return values, error scenarios, or how the account parameter relates to available accounts. Sibling tools could provide some context, but the tool itself leaves gaps for an agent relying solely on the description.

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?

With only 33% schema description coverage, the description needed to compensate but barely does. It mentions 'specified recipients' which covers the 'to' parameter, but does not explain subject, body, cc, bcc, or account beyond a vague reference to 'selected local account'. This leaves users guessing about required fields and defaults.

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?

The description clearly states the action with a specific verb ('Send'), the resource ('Apple Mail message'), and the source context ('from the selected local account'). It distinguishes itself from sibling tools like apple_mail_list and apple_mail_get by focusing on sending rather than reading or managing.

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?

The description provides some context ('from the selected local account') but does not explicitly state when to use this tool versus alternatives, nor does it mention prerequisites like listing accounts or needing a subject. The usage is implied by the verb 'send' but without concrete guidance or exclusions.

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