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

Annotations already declare readOnlyHint=true, openWorldHint=true, and idempotentHint=true, so the safety profile is covered. The description adds useful behavioral context: it discloses that previous/next episode are included only 'when the source has them', and that the timezone parameter affects rendering of those air times. It doesn't describe pagination or rate limits, but for a read-only fetch with an output schema, the added context is sufficient.

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?

Three sentences, each earning its place: the first states the resource and contents, the second gives provenance, the third routes to siblings. The key scoping information is front-loaded, and there is no repetition of schema or annotation content.

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?

For a read-only fetch tool with an output schema, the description is complete. It covers what the tool returns, where the id comes from, how the timezone parameter behaves, and which siblings to use for other data. The annotations cover safety, and the output schema covers return structure, so nothing essential 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?

Schema description coverage is 100%, so the schema already documents both parameters well. The description adds value by explaining the provenance of show_id (from search/lookup/schedule) and by clarifying that timezone is for rendering episode air times, which reinforces the schema's description. This goes slightly beyond the baseline 3.

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 a specific verb ('Fetch') and resource ('a television show by its TVmaze id'), and enumerates exactly what is included: full profile, weekly broadcast slot, season list, and previous/next episode when available. It also distinguishes itself from sibling tools by naming tvmaze_search_shows, tvmaze_lookup_show, tvmaze_get_episodes, and tvmaze_get_cast, so an agent can clearly tell it apart.

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?

The description explicitly says this is the entry point for an id returned by tvmaze_search_shows or tvmaze_lookup_show, and explicitly routes the agent to tvmaze_get_episodes for the episode list and tvmaze_get_cast for credits. This is clear when-to-use and when-not-to-use guidance with named alternatives.

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