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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It conveys that this is a read-only lookup returning candidate matches with years, which is useful. However, it does not explicitly state the absence of side effects, authentication needs, or rate limits, and it gives no detail on the structure of the returned candidates. This is adequate but not comprehensive.

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 with no filler. The first sentence front-loads the core functionality, and the second sentence provides actionable usage guidance. Every word earns its place.

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 two-parameter lookup tool with no output schema, the description covers the core purpose, the invocation context, and the general return shape (candidate matches with years). It could be more explicit about what happens when no matches are found or about the exact output format, but these are minor gaps in an otherwise self-sufficient description.

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%, so the parameters are already fully documented in the input schema. The description reinforces that 'query' is a title search and that 'type' selects among movie/TV/album, but it adds little beyond the schema's own descriptions. Baseline 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 states a specific action ('Look up') on a well-defined resource ('a movie, TV show, or music album by title') and clarifies the output ('return candidate matches with years'). This clearly distinguishes it from sibling tools compose_design and list_formats, which have entirely different purposes.

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 explicitly says when to use this tool: 'when the user's title is ambiguous and you want to confirm which one they mean before composing.' It provides clear context for invocation, although it doesn't explicitly name excluded alternatives or when-not-to-use conditions.

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