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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety profile is covered. The description adds that data is sourced from the modern show page's listener-cohort recommendations, which is useful provenance, but it offers no rate limits, auth, or fallback behavior. Adequate but not rich.

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 purpose is good, but roughly half the text duplicates the input schema's Country and Limit descriptions, which adds length without new information.

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, return values need not be explained, and the description covers purpose, params, and an alternative tool. Minor gap: no note on pagination or what happens when fewer than Limit results exist.

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 description coverage is 100%, and the description merely restates the Country and Limit definitions verbatim from the schema. No added semantics such as valid ranges, storefront behavior, or defaulting edge cases. Baseline 3 is correct.

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 verb ('Returns') and resource ('You Might Also Like rail for a single show') and clarifies the data source (listener-cohort recommendations). An agent can immediately distinguish this from apple_podcasts_show and apple_podcasts_show_episodes.

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?

Explicitly routes to apple_podcasts_show for show details, which implicitly frames this tool as being for recommendations rather than metadata. However, it doesn't state when NOT to use it (e.g. vs. search or charts).

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