Set property value

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

Annotations only say write, non-destructive, idempotent; the description adds the important hidden behavior that a keyframe is set implicitly when time is given or the property is already animated, plus that the new property state is returned. It stops short of mentioning side effects such as undo or checkpointing and behavior on expression-driven properties.

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 the core action, then the keyframe rule, then examples, then alternatives — a sensible order. The examples cluster is dense and slightly repetitive with the path schema examples, but each sentence still carries information needed to call the tool.

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?

With five parameters, no output schema, and an annotation profile that covers safety, the definition covers the return value, the failure case, the implicit-keyframe gotcha, and the sibling routing needed to pick the right tool. Nothing an agent needs in order to invoke it correctly is missing.

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 3 is the baseline; the description earns more by pairing example paths with example values (path 'Transform/Opacity' value 50; 'Effects/Fill/Color' '#ff0000'), showing accepted value shapes. The time parameter's keyframe-replacement semantics are restated but gain the extra animated-property caveat.

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?

A specific verb plus resource ('Set the value of any property') scoped to transform, effect parameter, shape attribute and text, so the range is unambiguous. Concrete examples (Transform/Opacity, Transform/Position) and explicit sibling routing make it distinguishable from ae_set_keyframes and ae_set_effect_params.

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 states the alternative tools and the condition that selects each: 'For several keyframes with easing use ae_set_keyframes, for expressions ae_set_expression, for many parameters of one effect ae_set_effect_params (via ae_call).' It also names the failure conditions (path is a group or not found), which is clear guidance on when this call will fail.

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