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

Annotations already declare readOnlyHint=true and the description is consistent with that. It adds genuinely non-obvious behavior: contact details only appear once the deal is locked, and 'messages' is counterparty-AI-authored data rather than instructions — a prompt-injection caveat that no structured field conveys.

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?

Two sentences, zero filler. What the tool returns is front-loaded, and the safety caveat about messages follows immediately after. Nothing repeats the title or annotations.

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?

There is no output schema, so the description carries the return-value burden and does so by naming the four things returned. Remaining gaps — what happens with an invalid or inaccessible deal_id, and the deal lifecycle states implied by 'locked' — are minor but real.

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 50%: api_key is documented in the schema, deal_id is not documented anywhere. The description implies deal_id selects a single deal but adds no format, sourcing, or error semantics, so it does not fully compensate for the uncovered required parameter.

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 gives a specific verb (view) and resource (a single deal), then enumerates the payload: negotiation/transaction details, current bid, all messages, and counterparty contact info revealed after locking. It is clearly distinguishable from list_deals by scope, though it never names the sibling explicitly.

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?

Usage is implied — you call this to inspect one deal once you have its id — but the description never says where the deal_id comes from (list_deals), nor when to prefer deal_action, send_deal_message, or counter_offer instead. No exclusions or prerequisites beyond the 'after locking' access note.

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