justwatch_new

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

The description discloses specific behavioral constraints: 'Type accepts only `all`, `movie`, or `show`; limit defaults to 20 and clamps to 50.' This adds value beyond the schema. However, with no annotations provided, it fails to disclose whether the operation is read-only, whether authentication is required, or what the response structure is, which would be helpful for a complete behavioral picture.

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 two sentences, front-loading the core purpose and then listing constraints. It is efficient and free of fluff. It could be slightly more compact by not repeating details already in the schema, but it remains well-structured and scannable.

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 read-only retrieval tool with four optional parameters and no output schema, the description covers the essential behavior: what it returns, the type restriction, and limit behavior. It lacks an explicit read-only hint (not provided in annotations) and doesn't describe response format, but since no output schema exists, the agent can reasonably infer a list. The description is adequate for correct invocation.

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% and each parameter has a description. The tool description essentially repeats the schema's notes on type and limit (e.g., enum values and default/clamp behavior) without adding new meaning. Since the schema already carries the semantic load, the description adds no extra parameter context, warranting the baseline score.

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 states a specific verb and resource: 'Get new JustWatch titles' and clarifies it returns 'newly available movies and shows'. This is clear and distinguishes it from general search tools, though it doesn't explicitly compare to sibling tools like justwatch_popular or justwatch_discover, which could also return titles. The intent is unambiguous.

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 gives no guidance on when to use this tool versus alternatives. It does not mention other JustWatch tools (e.g., justwatch_search, justwatch_popular) or provide any exclusions or conditions for selection. Usage is only implied by the tool name and purpose, leaving the agent to infer suitability.

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