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

Annotations already declare readOnly, openWorld, and idempotent hints. The description adds valuable non-obvious behavior: when a show is absent from TVmaze, the tool reports a miss with guidance rather than raising an error. This edge-case disclosure goes beyond what the annotations and schema provide.

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?

Two sentences with no filler. The core action and use case come first, and the miss-handling behavior is a distinct, valuable second sentence. Every element earns its place.

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?

The tool is simple, the annotations cover safety and idempotency, the output schema documents the return value, and the description covers the failure mode. No necessary information is missing for an agent to select and invoke this tool correctly.

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?

Input schema coverage is 100%, with each source variant and external_id pattern fully documented. The description adds no new parameter-level meaning beyond restating the three catalogs, so the schema carries the semantic weight. This matches the baseline for full schema coverage.

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 names a precise verb and resource: resolve an external catalog id (IMDb, TheTVDB, TVRage) into a TVmaze profile. It also conveys the distinguishing scope — this is a cross-reference lookup, not a search or a direct TVmaze-id fetch — which separates it from siblings like tvmaze_get_show and tvmaze_search_shows.

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 states when to use it: 'Use this to cross a show id from another source into TVmaze.' This is clear contextual guidance. It does not explicitly name sibling alternatives or exclusion conditions, but the use case is unambiguous enough that an agent can route correctly.

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