APIbase

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=true, so the description does not need to repeat these safety properties. The description adds '(TMDB)' to identify the external data source, which aligns with openWorldHint. It does not contradict annotations, but also does not disclose additional behavioral traits like rate limits or pagination details beyond what the schema provides.

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, information-dense sentence with no filler words. It front-loads the action ('Discover') and immediately follows with the filterable dimensions and source identifier. Every element earns its place in the character budget.

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 rich input schema (13 well-documented parameters) and comprehensive annotations, the description provides sufficient context for selection. It appropriately omits redundant parameter details covered by the schema. Minor gap: it does not mention that all parameters are optional or hint at the response structure, though this is partially mitigated by the 'Discover' framing implying a list result.

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?

With 100% schema description coverage, the baseline is appropriately 3. The description provides a high-level conceptual grouping of parameters ('by genre, year, rating...') but does not add semantic details, syntax examples, or clarifications beyond what the schema already documents for each of the 13 parameters.

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 identifies the resource (movies/TV from TMDB) and lists specific filtering dimensions (genre, year, rating, language, sort order). It implicitly distinguishes from the sibling 'search' tool by emphasizing filter-based discovery rather than text queries, though it could explicitly state 'use for browsing when you don't have a specific title'.

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 by listing filterable attributes (genre, year, etc.), suggesting when to use the tool. However, it lacks explicit guidance contrasting it with siblings like 'tmdb.movies.search' (text search) or 'tmdb.movies.trending', leaving ambiguity about which tool to select for similar use cases.

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