Animate a property

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

The description discloses two useful behavioral traits: existing keyframes at the same times are replaced, and easing defaults to smooth ease in and out. With only readOnlyHint=false and openWorldHint=false annotations, this context adds value beyond the structured fields and does not contradict them.

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 sentences, front-loaded with the core action, followed by scope clarification and key behavior. Every sentence earns its place; there is no filler or repetition of schema details.

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?

Given the 9-parameter schema with 89% coverage, the description is adequately complete for correct invocation. The key behavioral details (replacement and easing default) are present, while remaining parameter semantics are well covered by the schema. It does not describe return values, but no output schema exists and the description isn't expected to.

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 description coverage is high (89%), so the baseline is 3. The description adds value by explaining the default easing in human terms ('smooth ease in and out') and by listing property categories such as mask paths, shape properties, and text animators that go beyond the schema's examples. This meaningfully supplements the schema.

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 states a specific verb and resource: 'Set keyframes on any animatable property', followed by a concrete list of property categories. This clearly differentiates it from siblings like ae_set_property (static value) and ae_remove_keyframes (removing keys), even without naming them.

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 action is clear, and the broad 'any animatable property' implies when to use it, but there is no explicit guidance about alternatives or when not to use it. An agent would benefit from a pointer to ae_set_property for static values or ae_remove_keyframes for clearing keys, but the description leaves this inferred.

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