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

Annotations already cover read-only, idempotent, non-destructive and closed-world, so the bar is lower, and the description still adds real substance: the inclusion threshold of 8 films, the rule that consecutive feature/demo passages count as one beat, the length-band constraint, and the returned fields (film count, median length, example films). What it does not disclose is scale — roughly how many formulas exist — which matters for deciding whether to filter.

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 tight sentences plus a filter clause, with no filler and the core definition front-loaded. The minor weakness is that it opens by defining 'formula' rather than stating what the tool returns, so the action verb only appears in the title.

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?

With an output schema present and annotations covering the safety profile, the description only needs to explain the concept and the filters, which it does well. The remaining gap is navigational — no routing to the near-duplicate siblings or indication of result volume.

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 0%, so the description must carry the parameter meaning and it largely does: 'band' is identified as the length band and 'contains' as a beat the formula must include. It does not explain what short/mid/long/extended mean in practice (seconds or beat counts), leaving the enum values semantically opaque.

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 defines the resource precisely — recurring beat sequences shared by at least 8 published films within the same length band — so an agent knows exactly what a 'formula' is. It never states the verb 'list' explicitly (only the title does) and gives no sibling differentiation from get_formula, typical_structure, or pattern_search.

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?

There is no when-to-use guidance and no named alternative. An agent cannot tell from this text whether to reach for list_formulas, get_formula (single formula), typical_structure, or pattern_search for a given question; the only hints are the two optional filters, which are parameter facts rather than usage routing.

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