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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the description's burden is lighter. It adds genuinely non-obvious context: only stations that play in a browser over a secure connection are listed, results cap at `limit`, and filter values must match OndaCast's English display names.

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?

Front-loaded with the core purpose and sized well at four sentences. The only waste is the OndaCast page link being mentioned twice (once in the return summary, once in the 'for finding a station' sentence), a minor redundancy rather than a structural problem.

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 an output schema present and full annotation coverage, the description need not explain return shapes. It supplies the result-set restriction, filter conventions and intended use, leaving only minor gaps such as result ordering and no explicit handoff to get_station for details.

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 description earns above that by establishing a cross-parameter convention — country, genre and language all use the English names shown in OndaCast's filters — which the schema only partially states (it never says genre must be an English display name). It adds no guidance on query matching semantics, but the schema covers the constraints.

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 opening sentence names a specific verb (search), resource (live radio stations), catalogue (OndaCast) and the optional narrowing filters, so an agent can immediately tell this apart from get_station, get_charts or radio_guide_now. The scope sentence ('for finding a station to listen to or play') further pins down intent.

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 states the use case clearly ('finding a station to listen to or play') and the follow-up action (each result links to the station's page). It never explicitly says when NOT to use it or names a sibling such as get_station for station detail, so it stops short of full routing guidance.

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