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

With no annotations, the description carries the full load and does well: it discloses provenance (source URL and date verified), cache-vs-live behavior, and a real side effect — that requesting a missing platform records the ask with the owner. It leaves out response ordering/pagination and error behavior for unknown platforms.

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?

It is front-loaded with what the entries contain, which is good, but the parenthetical platform list and the duplicated method examples repeat the schema verbatim and inflate the length. The final sentence about missing platforms is genuinely earning its place; the enumerations are not.

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 no annotations, so the description must describe the return shape — and it does, listing the fee components plus source URL and verification date. It is nearly complete for a 3-parameter, all-optional read tool, missing only result ordering and behavior when no filter is supplied.

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; the `fresh` parameter already documents its rate limit and slowness in the schema. The description does add one thing the schema does not: that platform and method filters combine as 'and/or', but it also duplicates the enum lists rather than adding new meaning.

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 states the resource precisely: 'raw, sourced fee entries' with named fields (percent, fixed fee, caps, minimums, extras, source URL, date verified). This implicitly separates it from sibling tools like explain_fees and my_effective_rate, but it never names a sibling or states the contrast explicitly.

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?

'Use it to quote a provider's exact pricing or to check a number' gives a clear use context, and the filter-by-platform/method sentence clarifies how to narrow results. There are no explicit exclusions or named alternatives (e.g., when to prefer explain_fees), which keeps it short of a 5.

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