set_knob

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

Annotations already establish idempotentHint=true and destructiveHint=false, so the agent knows repeat calls are safe and nothing is destroyed. The description adds the type-dependent nature of the value argument but says nothing about validation failures, whether the knob must exist, or error behavior. Adequate but thin given the annotations carry the safety profile.

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?

Short and front-loaded, with the operation in the first sentence and parameters listed after. The Args block mostly duplicates the schema, which is mild waste, but the whole thing is compact overall.

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 simple 3-param mutation with no output schema, the description is minimally sufficient. It lacks any note about which node/knob combinations are valid or what happens on failure, but the schema and annotations cover the essentials.

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 all three params already carry their meaning in the schema, and the Args block largely repeats it. The one added nugget is 'type depends on the knob' for value, which warns the agent to match the knob's expected type. Otherwise baseline 3 applies.

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?

Clear specific verb (set) plus resource (knob value on a node). It distinguishes itself from the sibling get_knob, which reads the value rather than writing it. It doesn't explicitly call out that distinction, but the verb picks it out.

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?

Setting a knob value is implicitly the right tool whenever a knob needs to change, and get_knob is the obvious read counterpart. But there's no explicit when-to-use guidance, no note about when to prefer set_expression or set_keyframe for animating that same knob.

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