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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=false; the description adds the crucial human-in-the-loop workflow (draft, then send only after manufacturer confirmation) and notes the supplier-token auth path. That is meaningful behavior beyond the structured hints, though it omits rate limits or whether the message is visible externally.

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?

A single dense sentence, front-loaded with the audience and auth requirement, with no filler sentences. The parenthetical and em-dash clause make it dense but every clause carries 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?

With no output schema and annotations covering the safety profile, the description supplies the audience, the match precondition, file-attachment source, message kinds, and the confirm-before-send workflow. The main residual gap is what rfq_id denotes and the meaning of the 'note' kind.

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 20%, so the description must carry the load; it partially does by tying file_ids to upload_rfq_file and enumerating message kinds, but it omits 'note' from the enum it lists and says nothing about rfq_id or body. Two of five parameters remain effectively undocumented outside a minimal 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?

The description names a specific verb and resource ('write to the buyer of a request you were matched to') and scopes the audience to a manufacturer's agent, so the action is unambiguous. It does not, however, distinguish itself from the sibling 'send_rfq_message', which an agent would need to disambiguate before choosing.

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?

It gives clear context for use: you must be a manufacturer's agent matched to the request, and the message may be a question, answer, or update. The 'draft it for the manufacturer and send only after they confirm' instruction adds real operational guidance, but no alternative tool is named and no when-not condition is given.

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