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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real behavioral context: routing is determined by saved per-scene voice choices with native speech as fallback, audio-off prices are unavailable for speaking scenes, and operationId has retry-stable semantics. This is meaningful context beyond the annotations, though it does not cover auth or rate limits.

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?

Front-loaded with what is returned, then include behavior, then behavioral notes. Dense but each clause carries information; it reads as a single packed paragraph rather than cleanly separated points, which slightly hurts scannability.

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?

An output schema exists so return values need not be explained, yet the description still usefully frames the return surface and the include-based variations. Combined with annotations it is nearly complete, missing only auth/permission requirements.

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%, so the baseline is 3; the description adds meaning beyond the schema by explaining what 'languages' exposes (nativeSpeechLanguages, nativeSpeechEngines as model-specific evidence), what 'artists' returns, and the retry-stable nature of operationId. The include guidance largely restates the schema description, keeping it from a 5.

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?

States a specific verb (returns/reads) and a rich, enumerated resource set: Film scenes, dialogue, cast, voice assignments, planning state, savedPlan.revision. An agent can distinguish this read tool from the many studio_film_* write siblings (scenes_write, script_write, assign_actor) without opening either schema.

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?

Gives conditional usage for the include options (add 'languages' / 'artists', omit for the project view) and clarifies that operationId reads prior plan progress 'without starting or settling work', implicitly distinguishing it from tools that initiate work. It never names a specific sibling alternative, so it stops short of a 5.

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