get_movie_credits

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

With no annotations provided, the description carries full burden but only states what data is returned (actors with characters, crew with roles/departments). It lacks behavioral details like whether this is a read-only operation, rate limits, authentication needs, error conditions, or pagination behavior for large casts.

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 perfectly concise with two sentences that each earn their place: the first states the purpose, the second specifies the return format. It's front-loaded with the core functionality and wastes no words.

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 single-parameter read tool with no annotations and no output schema, the description is adequate but incomplete. It explains what data is returned but not the structure, format, or potential limitations. Given the simplicity, it meets minimum requirements but lacks depth for optimal agent understanding.

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 has 100% description coverage (movie_id parameter is fully documented as 'TMDB movie ID'), so the baseline is 3. The description adds no additional parameter information beyond what the schema already provides, maintaining the minimum viable level.

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 clearly states the tool's purpose with specific verbs ('Get cast and crew information') and resource ('for a specific movie'), distinguishing it from siblings like get_movie_details or get_tv_credits by focusing on personnel data rather than general movie info or TV credits.

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 when needing cast/crew data for a movie, but provides no explicit guidance on when to use this versus alternatives like get_movie_details (which might include credits) or search_people. It lacks explicit when-not-to-use or prerequisite information.

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