add_fcurve_modifier

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

With no annotations, the description must disclose behavioral traits. It only states that it adds a modifier and that settings are its properties, but it does not explain side effects (e.g., whether existing modifiers are overwritten), permissions, return values, or what happens with invalid input. For a mutation tool, this is a significant gap.

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 a single concise sentence that front-loads the action and type list. It is efficient and easy to parse, though it sacrifices detail for brevity. It earns a 4 for being compact and direct.

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 4 parameters, no output schema, and no annotations, the description is severely incomplete. It fails to explain the purpose of 'object' and 'data_path', does not mention return behavior, and provides no usage context. An agent would be hard-pressed to call this tool correctly without additional documentation.

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 0%, so the description must compensate. It explains 'type' by listing examples and notes that 'settings' are properties, but it does not explain 'object' or 'data_path'. These are critical for calling the tool correctly, leaving the agent to guess their meaning. The description adds partial value but is not sufficient.

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 the action clearly: '给 fcurve 加修改器' (add modifier to fcurve) and lists supported types (CYCLES/NOISE/LIMITS/STEPPED/GENERATOR…). It is specific about the verb and resource, and the type enumeration gives useful detail. However, it does not explicitly differentiate this from the sibling add_modifier tool, which likely handles object modifiers, so it relies on the resource name for distinction.

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 provides no guidance on when to use this tool versus alternatives. It does not mention that add_modifier is for object modifiers, nor does it state prerequisites (e.g., having an fcurve selected or a valid data_path). An agent must infer usage from context, which is insufficient.

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