apply_animation_style

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

With no annotations, the description carries the full burden and largely succeeds: it discloses that duration/timelineOffset are top-level rather than nested in props, that it returns an instance id, and the non-obvious fact that applying a style does not materialize tracks into animations. It omits auth/permission and error/rate behavior, but the semantic gotchas are well covered.

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 core action is front-loaded and each sentence adds information about identification, units, return value, or verification. It is dense but avoids filler, though it reads as a run-on sequence rather than cleanly separated concerns.

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 9-param mutation tool with no annotations and no output schema, the description supplies the critical path: how to identify the style, unit semantics, the return value, its downstream consumer, and how to verify the result. The gap is the undocumented secondary params (extendTimeline, allowTopLevelFrame, props).

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% across 9 params, so the description must compensate. It clarifies styleId, styleName (substring match), duration, and timelineOffset (seconds, top-level not props), but leaves name, props, nodeId, extendTimeline, and allowTopLevelFrame undocumented, so compensation is only partial.

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 first sentence states a specific verb and resource ('Apply a reusable animation style to a node'), and the mention of remove_animation_style plus the returned instance id distinguishes it from adjacent animation tools. An agent can identify the action without opening the 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?

It names list_animation_styles as the source for styleId and remove_animation_style as the consumer of the returned instance id, giving clear routing context. It stops short of an explicit when-to-use/when-not statement, but the identification instructions make usage unambiguous.

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