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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the safety profile is conveyed structurally. The description adds only a pricing note and says nothing about the irreversible consequence of sending, whether the draft is consumed, or auth requirements — so it contributes little behavioral value beyond the annotations.

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 text is short but that brevity is under-specification, not conciseness. The only substantive content is an embedded pricing comment block, which is not what the agent needs front-loaded for invocation.

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?

An output schema exists, so return values need not be described, but for a destructive, non-idempotent send operation with a nested parameter object the description omits nearly all context an agent would need to invoke it confidently.

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 coverage is only 67% and the description mentions no parameters at all. It does not clarify draft_id vs inbox_id, nor the nested body object with add_labels/remove_labels, leaving the agent reliant entirely on the schema.

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?

"Send Draft" merely restates the title "Inboxes - Send Draft" and the tool name. It conveys a verb and a resource, but with no scope, no target identifier, and no differentiation from sibling senders like post_agentmail_inbox_message_send, it reads as a tautology rather than a purpose statement.

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?

No guidance whatsoever on when to use this versus post_agentmail_inbox_message_send or post_agentmail_inbox_draft (create draft). The agent must infer from the name that this promotes an existing draft to a sent message; nothing states prerequisites or alternatives.

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