mail_send_draft

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

The description mentions the destination restriction and return value, but does not clarify whether sending deletes the draft or other side effects. Annotations set destructiveHint=false, but the description does not confirm or deny this, leaving some behavioural ambiguity.

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 three sentences with no fluff. It front-loads the purpose, then adds restrictions and return info efficiently.

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?

The description covers purpose, restriction, reply usage, and return value. Output schema exists (keys: id). It is fairly complete for a simple send tool, though it could mention the fate of the draft after sending.

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%. The description adds meaning for 'to' (restricted to user email) and 'in_reply_to' (for replying), but subject and body are not elaborated. This provides partial compensation but not full coverage.

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 what the tool does: 'Send a draft email from Hermes's account to the user's own inbox.' This is a specific verb-resource combination, and it distinguishes this tool from siblings like mail_archive or mail_get, which do not send emails.

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 specifies that the destination is restricted to the configured user email, which guides when to use it (only for self-addressed drafts). It also mentions using in_reply_to from mail_get for replying, indicating a specific use case. However, it doesn't explicitly state when not to use it or list alternatives.

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