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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds value beyond them by listing the returned fields and explaining that episode data is deliberately excluded because it is fetched live. It does not say what happens for an unknown slug (error vs empty), which keeps it from a 5.

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 payload list, then retrieval guidance, then the episode exclusion. Nearly every clause earns its place; the trailing 'site and page' phrasing is slightly opaque and the served-by line is boilerplate.

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?

No output schema exists, so the description compensates by enumerating the returned fields, and the single required parameter is fully explained. For a one-parameter read tool with rich annotations, nothing essential to a correct call is missing.

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?

With only one parameter at 0% schema coverage, the description carries the burden and does it: it defines what a slug is, where to obtain one, and its URL form /podcast/<slug>. It stops short of stating case sensitivity or exact formatting rules for slugs.

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 and resource ('One show by slug') and enumerates exactly what comes back: title, publisher, description, episode count, cadence, language, categories, feed URL, site and page. That field list immediately separates it from list_shows and search.

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 explains where slugs come from (search, list_shows, the /podcast/<slug> page URL) and explicitly routes the episode use case to list_episodes, with the reason: episodes are read live from the publisher's feed. An agent knows both when to use this and which sibling to pick instead.

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