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

Annotations already declare readOnly, idempotent, closed-world, non-destructive behavior, so the safety profile is covered. The description adds genuine value beyond that by describing the payload shape (name, what it works out, page link, embed address) and that the calculators are free. It stops short of noting pagination, result limits, or empty-result behavior.

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?

The front-loaded purpose is strong, but the 18-item parenthetical catalogue of calculator types consumes most of the text and could be compressed to categories. It also omits, in that space, more useful facts such as whether an unfiltered call returns everything.

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 the needed work by specifying returned fields (summary, page link, embed address) across two source sites. For a single optional-parameter list tool this is nearly complete, missing only pagination and behavior with an empty query.

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% and the single query parameter is already documented as matching name, summary, or keywords. The description only adds a worked example ('mortgage'), which is mildly useful but not meaningfully beyond the schema. Baseline 3 applies.

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 makes clear this lists Points Frog money calculators plus the Cruises Frog drinks package calculator, and returns each one's summary, page link, and embed address. The resource is distinctive versus siblings like get_embed_code or list_articles. It loses a point because the verb ('list/return') is buried inside a long parenthetical catalogue rather than stated up front.

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?

'Narrow by words such as "mortgage"' gives concrete guidance on using the filter, and the calculator examples imply discovery use. But there is no explicit statement of when to call this versus get_embed_code (which also concerns embed addresses) or other list_* tools, and no when-not guidance.

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