set_shape_key

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

The description discloses that the tool creates the shape key if it does not exist and includes the Basis key, which are important behavioral details. With no annotations provided, this transparency helps the agent understand side effects, though it does not mention any destructive actions (none apparent).

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 description is extremely concise, using two short clauses to convey the core operation and the optional keyframe behavior. Every word is necessary, making it highly efficient and easy to parse.

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 simplicity of the tool, the description is sufficiently complete: it covers the action, creation behavior, and the conditional keyframe insertion. It does not mention a return value, but none is expected, and the context provided aligns with the tool's purpose.

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?

The description does not explain the 'object', 'name', or 'value' parameters individually; it only clarifies 'frame' behavior. Since schema description coverage is 0%, the description must compensate, but it only partially does so for one parameter, leaving the others ambiguous without additional context.

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 clearly states the action (set shape key value) and the resource (shape key on an object), including the creation behavior if the key does not exist. It is distinct from sibling tools like list_shape_keys or delete_keyframe, providing precise intent.

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 description explicitly mentions the optional frame parameter and its effect (also insert keyframe), giving clear guidance on when to use that parameter. It does not explicitly contrast with alternative tools, but the context is clear enough for a simple operation.

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