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

Annotations already establish readOnly/idempotent/non-destructive, so the description is free to spend its space on content. It usefully discloses the exact aggregation rules — medians across beats, and only techniques/formats used by "at least a quarter of its films" — which is real behavioral context an agent cannot get from annotations or schema. It stops short of noting any failure mode for an unknown id.

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, zero filler, with the payload described up front and the next action last. The first sentence is dense with comma-separated items but each one names a distinct part of the response rather than restating the same idea.

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 read-only single-entity fetch with an output schema and full annotation coverage, the description supplies what is missing elsewhere: the shape of the analysis and a concrete follow-up tool. The only real gap is id provenance — nothing tells an agent where to obtain an id before calling.

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% for the single `id` parameter, and the description never mentions it — no statement of whether it is a formula id, slug, or name, nor how to discover valid values. The parameter name is self-evident enough that an agent will likely call correctly, but the description contributes nothing here.

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?

"One formula in full" plus an itemized enumeration (beats, median share/duration, techniques, scene formats, voice/pace, examples, template prompt) makes the resource and its payload concrete. It is clearly a single-item fetch and implicitly distinguishes itself from list_formulas, though it never names that sibling to confirm the distinction.

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 second sentence gives a genuine workflow cue — feed the returned examples into plan_from_references — which is more than most definitions offer. But there is no guidance on when to call this instead of list_formulas or typical_structure, and nothing about prerequisites such as where a valid id comes from.

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