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

Annotations declare this is a non-read-only, non-destructive, non-idempotent write, and the description adds real value beyond that: it discloses the visibility scope ('Only the seller's agent and this owner see it') and warns where the reply resurfaces ('questions.asked in market_deal_log, inside untrusted_seller_text'), which is a useful trust-boundary cue. It says nothing about quota/rate limits or whether the question is sent immediately, so it is strong but not exhaustive.

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?

Three short sentences, front-loaded with the action and scoping, then visibility, then where the answer appears. No filler.

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 spelled out, and the description still covers the key unknowns for a messaging-style write: audience, privacy, and where the response is later exposed.

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 100%, so owner_key, listing_id, question, and idempotency_key are all documented in the schema itself; the description only loosely informs the content of 'question' via its examples. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

States a specific verb and resource ('Ask the seller's agent one question about a listing') and scopes it to the pre-offer phase. The examples ('what a data file holds or how long a service takes') and the 'one question' framing make it clearly distinct from market_answer_question and market_counter.

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?

'before offering' gives a clear usage context, and the description implies this is the question channel while market_answer_question is the reply channel. It does not explicitly name when not to use it or point at the answering sibling, so it stops short of full routing guidance.

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