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

With no annotations, the description carries full burden. It discloses the prerequisite (movies_enabled) and states the output categories and fields. It does not mention side effects or permissions, but being a listing tool, these are implicit.

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?

Two sentences front-load the key purpose and condition, then details categories and output fields. Every sentence earns its place—no redundancy or fluff.

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 lack of output schema, the description covers return fields and parameter behavior. It omits pagination details but mentions the limit parameter implicitly. Overall, it is sufficiently complete for a list tool.

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 100% with parameter descriptions already present. The tool description reinforces the status parameter's meaning through examples ('now-showing' = films with upcoming showtimes) but does not add significant new information beyond the schema.

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 lists movies with specific categories (now-showing, coming-soon, streaming) and includes key fields like title, genres, rating, runtime, and URL. It distinguishes from sibling tools like get_showtimes, which focus on showtimes rather than movie listings.

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 browsing movie catalogs and notes the prerequisite 'only on sites with movies_enabled.' While it doesn't explicitly exclude other tools, the context is clear and no sibling tool duplicates this function.

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