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

Annotations already establish read-only and non-destructive behavior, but the description adds useful context: subscriber-only season access, ambiguous-name candidate lists, and the shape of returned detail such as age reason, mood, main irritant, and score. It does not cover auth requirements or rate limits beyond the subscriber note.

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?

The description is a single dense sentence that front-loads the core lookup behavior and key return cases. The domain term 'door' is slightly opaque, but otherwise there is little wasted text.

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?

An output schema exists and annotations cover safety, while the description still explains result shape, ambiguous-name handling, and subscriber gating. It is adequate for a simple lookup tool, though parameter-specific behavior such as language and year filtering is not elaborated.

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 75%, with query, type, and year documented in the schema. The description restates that query can be a name or id but adds little about lang, year, or type beyond what the schema already says, so baseline 3 is appropriate.

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: find one film or series by name or id, plus what is returned and how ambiguous names behave. It does not explicitly contrast with the sibling search_titles tool, so it is clear but not fully differentiated.

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?

Usage is implied: use this for a single known title by name/id, and an ambiguous name returns a short candidate list. It does not explicitly say when to use search_titles instead or when not to use this tool.

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