Update email draft

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

The description discloses an important non-obvious behavior: the revision requirement as an optimistic-locking mechanism, preventing stale agent actions from overwriting newer content. It also clarifies that the operation does not send email. This adds meaningful behavioral context beyond the empty annotations, though it does not explain partial-update semantics or the response shape.

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 short, purposeful sentences. The primary use is stated first, the critical revision constraint is next, and the non-sending behavior is last, with no filler or redundant information.

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?

Given nine parameters, zero schema descriptions, no output schema, and no helpful annotations, the description is not complete enough for reliable invocation. It covers the core edit action and revision locking, but leaves critical behaviors such as how optional fields affect the draft and how to obtain the current revision unstated.

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 schema description coverage at 0%, the description carries the full burden for explaining parameters, but it only clarifies revision. It does not explain how to/cc/bcc/subject/bodyText/bodyHtml/attachments should be supplied or whether omitted fields are preserved or cleared during an update.

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 states a specific action and resource: "edit an existing prepared draft." It clearly distinguishes this from drafting, sending, and discarding by adding "It does not send email," leaving no ambiguity about the tool's role.

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 gives clear usage context: use when editing an existing prepared draft, and it warns that the current revision is needed to avoid overwrites. It explicitly rules out sending email, though it does not directly name alternative tools like mail_draft_create or mail_draft_send as comparisons.

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