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

Far exceeds the annotations (readOnly=false, openWorld=true, idempotent=false): it discloses the billing source (USDF balance, never free credit), the cost cap semantics (at most max_price, nothing on top), that a non-2xx unanswered call costs nothing or only what the seller kept, the 503 market_calls_unarmed gating, and the required Bearer auth. This is exactly the behavioral context a paid, open-world call needs.

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?

Front-loads the action and keeps nearly every clause load-bearing (cost, error, auth, return). The first sentence is long and clause-dense, verging on run-on, which slightly hurts scannability.

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, the description still states the return value ('the seller's answer and the receipt') and covers auth, cost, and error paths. Limits handling ('within the key's and its agent's limits') is mentioned but its failure behavior is not spelled out, a minor gap for this complexity.

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 the baseline is 3, but the description adds meaning beyond the schema: input is forwarded to the seller whose own policy governs it, and id is explicitly tied to agents_market_search output. The max_price rationale (seller price changes) also deepens the required-parameter understanding.

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 ('Calls a listing of the agents market by its id') and pins the id's provenance to the agents_market_search sibling, so an agent can separate it from search/quote tools without opening a schema. The scope is unambiguous.

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 clearly signals the prerequisite (the svc_... id comes from agents_market_search) and why max_price is mandatory (a seller may change its price). It does not explicitly route to the quote/quote_tool siblings for pre-call pricing, so the when-to-use-vs-alternatives guidance is implied rather than stated.

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