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

Annotations already declare read-only, idempotent and non-destructive, so the description correctly spends its words elsewhere: it discloses that every row carries source_url and as_of, that conversions are clearly labelled and FX-sourced, and that results are benchmarks rather than binding quotes. That provenance and caveat context is genuinely additive beyond the annotations.

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?

Four compact sentences, front-loaded with the resource and scope before the conversion and caveat clauses. The telegraphic fragments ('Benchmarks, not quotes.') are dense rather than wasteful, though the clipped style costs a little readability.

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 shape needn't be explained, and the description covers scope, provenance and conversion behavior. The remaining gap is behavioral detail on three undocumented parameters (limit paging, currency filtering, include_providers) for a six-parameter tool with no required fields.

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 only 33%, so the description should compensate more than it does. It does add real meaning for convert (a labelled conversion with FX rate, date and source) and covers provider ('or for one provider') and use_case ('for a job'), but limit, currency and include_providers are left entirely to the schema.

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 resource and scope: current sourced prices for a job or for a single provider, with provenance (benchmarks + provider-published). It implicitly contrasts with get_price_history via 'Current', but never names that sibling, so differentiation is inferred rather than explicit.

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?

'Benchmarks, not quotes' is a useful exclusion that steers quote-seeking agents toward the RFQ flow, but the description never says when to use this versus get_price_history or estimate_cost, both of which are close siblings. Usage is implied by the word 'current', not stated.

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