ctrl_set_value

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

Annotations already convey destructive write intent, and the description adds the low-level controller-track scope. It does not disclose details such as whether an existing key at the frame is overwritten or whether a controller must already exist, but the core behavior is stated.

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?

Two short parallel sentences (Chinese and English) deliver the action and the distinguishing caveat with no filler. The key information is front-loaded.

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 5-parameter tool with fully described schema and a destructive annotation, the description plus schema is sufficient to select and invoke it correctly. It lacks examples or edge-case notes, but those aren't required given the complete parameter docs.

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 100%, so the schema already documents all five parameters. The description adds no parameter-level detail beyond repeating 'controller track' scope; baseline 3 is appropriate.

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 names a specific action ('Write a keyframed value to an animatable controller track at a frame') and explicitly differentiates itself from anim_set_key by calling itself lower-level and aimed at controller tracks. This lets an agent distinguish it from the many sibling animation tools.

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 anim_set_key as the higher-level alternative and states that ctrl_set_value is for controller tracks, which gives clear selection context. It stops short of spelling out explicit when-to-use/when-not-to-use rules or exclusions.

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