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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuine behavioral detail beyond that: results are ordered cheapest first, the response includes a market index with median/quartiles/quotable extremes, and quotes are per 1,000 units.

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?

One dense sentence that front-loads the core answer and then appends ordering, index contents, and slug discovery. Every clause carries information, though the sentence is long enough that the guidance clause risks being skimmed.

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 does a fair job of sketching the return (sellers, price per 1,000, index statistics). It leaves the max-result behavior (limit up to 50), the trust-score filter, and any pagination unaddressed, which an agent would need to infer from the schema alone.

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 60%, and the description clarifies the two slug parameters (via list_services) and the price-unit normalization, plus the implied sort order. But limit and minTrust have no schema description and no mention in the description, so the gap is only partly compensated.

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+resource: it returns sellers of one service with price per 1,000, sorted cheapest first, plus a market price index. This is concrete enough that an agent can distinguish it from the more aggregate-sounding get_price_index and market_stats siblings.

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 one explicit prerequisite route: "Use list_services for valid platform and service slugs." However, it never says when to prefer this over the closely related get_price_index or search_panels siblings, so the primary when-to-use decision is left implicit.

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