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

With no annotations, the description is the only source of behavioral information. It discloses what data the tool returns (cast, trailer, external links), but doesn't mention read-only nature, potential errors, or required authentication. It doesn't contradict anything, but lacks depth.

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?

One concise sentence that conveys the core purpose without redundancy. It is front-loaded with the action and resource.

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 simple one-parameter get tool, the description is fairly complete: it states the scope (specific movie) and the content (cast, trailer, links). It doesn't mention error behavior or edge cases, but the lack of an output schema is partially compensated by listing returns. Overall, adequate but not exhaustive.

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?

The schema already fully documents the 'slug' parameter with a clear description. The tool description adds the context that the movie is specific, but doesn't add detail beyond the schema, so a baseline score of 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?

The description uses the specific verb 'get' with resource 'detailed information about a specific movie' and lists concrete content (cast, trailer, external links), distinguishing it from sibling tools like search_movies or browse_movies.

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 implies usage for looking up a single movie by its slug, but doesn't explicitly state when to prefer this over browse_movies or get_similar_movies, nor provide exclusion criteria. The 'specific movie' wording gives context but no explicit when-to-use or alternatives.

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