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

Annotations already flag destructiveHint=true and idempotentHint=true; the description resolves the apparent tension by explaining that the change is versioned ('saves it as the style's next version... earlier versions are kept'), which is exactly the context annotations cannot carry. The retry guidance reinforces idempotency but largely repeats the operation_id schema text.

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?

Three tight sentences, front-loaded with what the tool does, then side effects, then the retry rule. No filler and every clause carries operative information.

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 and annotations cover the safety profile, so the description only needs to supply the versioning model and retry discipline, which it does. Minor gaps remain around failure behavior (e.g., what happens if the plain-words request is ambiguous) and the role of style_id.

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 only 33%, with operation_id the sole documented field, so the description must compensate for `change` — and it does, specifying that the value is free-form natural language with worked examples. `style_id` is only implied by 'one of the linked account's saved styles' and never gets explicit semantics, which keeps it off 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 and resource ('Change one of the linked account's saved styles') and narrows the input modality to plain words, which separates it from set_caption_style, copy_style, and browse_styles. The examples ('bigger yellow captions, no zooms') make the operation concrete rather than abstract.

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 example phrasings imply what kind of request belongs here, and 'every later video in that style follows it' signals the scope of effect. But no sibling is named and no when-not-to-use guidance is given, so the agent must infer how this differs from set_caption_style or edit_video.

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