send-draft-email

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

The description explicitly flags this as a WRITE operation and states the safety requirement of confirm=true and user approval, which goes beyond what annotations alone provide. Annotations already indicate readOnlyHint=false and destructiveHint=false, so the description adds useful operational context without contradicting them.

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 a single, front-loaded sentence that communicates the action, the write nature, and the approval requirement. No filler or redundant content; every phrase adds value.

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 simple two-parameter tool with rich schema descriptions and annotations covering the read/write profile, the description plus schema provide enough to call it correctly. It doesn't describe return values, but for a send operation with no output schema this is a minor gap.

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 100%, with both parameters already documented well: messageId points to the draft created by create-draft-email, and confirm is described as a safety gate requiring user approval. The description itself adds little beyond restating the confirm requirement, but the schema carries the semantic load.

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 ('SEND') and the specific resource ('a previously created draft'), which distinguishes it from sending new mail. The parameter description further reinforces this by tying messageId to create-draft-email. An agent can immediately tell what this tool does and how it differs from send-mail.

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 context: use this to send a draft that was previously created, and require explicit user approval with confirm=true. It doesn't explicitly name alternatives or say 'do not use send-mail for drafts,' but the draft-specific wording makes the intended flow evident.

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