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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows this is a safe, non-mutating operation. The description adds value by indicating the return fields (id, title, year, rating, poster), which is useful context beyond the annotations. While it doesn't mention things like pagination or rate limits, the annotations cover the safety profile, so this is a strong score close to the maximum.

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 succinct and well-structured: it opens with the core purpose in the first sentence, lists return fields in the second, and closes with explicit exclusions in the third. Every sentence adds value, and there is no fluff. The key information is front-loaded, making it easy for an agent to parse quickly.

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?

Given the tool's moderate complexity (5 parameters, all documented in the schema) and the presence of full annotations (readOnly, idempotent, non-destructive), the description is complete for correct invocation. It covers the what, when, and why, and the schema covers the parameter specifics. The only minor absence is discussing pagination behavior, but that is a small gap against a well-specified schema.

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%, meaning all five parameters (query, type, page, limit, language) have clear descriptions in the schema itself. The tool description doesn't add much beyond that—it focuses on the overall purpose and return value. While the description mentions 'partial titles' for query, which the schema also includes, the schema already does the heavy lifting, so a baseline 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 clearly states that the tool searches movies, TV shows, and people by title or keyword, and lists what it returns (id, title, year, rating, poster). It distinguishes itself from siblings by explicitly excluding ranked-list questions (movies_compare_lists) and episodes (tv_episodes), making it stand out among the many search-related tools.

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 provides explicit guidance on when to use this tool: when the user asks about a film, series, or actor, or when a TMDB id is needed for another tool. It also states when NOT to use it, naming specific alternatives (movies_compare_lists for ranked lists, tv_episodes for episodes). This is exactly the kind of routing guidance that helps an agent select the right tool.

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