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

Annotations already establish readOnly, idempotent, non-destructive, non-open-world behavior, so the safety profile is covered. The description adds genuinely new behavioral context: the output composition (p25/median/p75/n/buyers/award-date range) and, importantly, the monetization rule that award rows with document URLs are paid. That paywall disclosure is not derivable from any structured field.

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 dense sentences with no filler: the first covers scope, classes, units and return fields; the second covers filtering, window semantics and the paywall. Front-loaded and efficient, though the first sentence packs enough clauses that it reads as a data dump rather than a lead statement.

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, and the description compensates by enumerating the returned statistics (p25, median, p75, n, buyers, award-date range). With only two optional parameters and annotations covering the safety profile, an agent has what it needs to call this correctly; only pagination/result-size behavior is unaddressed.

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 goes beyond the schema by defining the 'recent' enum value concretely (awards since 2024-01-01), which the schema only lists as 'all, recent or both (default both)'. It also clarifies that the class ids are discoverable from the result set, which the schema does not state.

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 resource (transaction price bands from public procurement awards), enumerates the exact asset classes covered (pad-mount and power transformers, MV switchgear, gensets, chillers) and the units of measure ($/kVA, $/kW, $/ton). This is far more specific than the sibling getters and an agent can immediately tell what data this returns.

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 explains how to narrow results ('Filter by class and window') and defines the 'recent' window semantics, which is useful invocation guidance. However, it gives no when-to-use vs when-not-to-use guidance and never references any sibling tool, so the routing decision is left entirely to inference.

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