ft_create_unified_expressions

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

With no annotations provided, the description carries full burden for behavioral disclosure. It only states the generative action and parameter options, omitting details on whether existing data is overwritten, permissions required, or side effects. The description is minimal and does not compensate for missing annotations.

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 concise: two sentences for purpose, two bullet-like lines for args. No redundant information, each sentence adds value. It is front-loaded with the main action.

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 tool's simplicity (2 parameters, no output schema), the description covers the main function and parameters. However, it lacks information about the result (e.g., what is generated, where it is stored) and does not address potential side effects. For a generation tool in a large sibling set, more context about output would improve completeness.

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 explain parameters. It does: 'mesh_name: Name of the face mesh' and 'source: ''arkit'' to map from existing ARKit shapes, or ''template'' for empty keys.' It adds context about default values and behavior beyond the schema's type/optionality.

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 specific action: 'Generate VRCFT Unified Expressions' from either 'existing ARKit shapes or from scratch'. It distinguishes from siblings like ft_create_arkit_shapes by specifying the target output (Unified Expressions) and the two source modes.

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 indicates two use cases via the 'source' argument (arkit vs template) but does not explicitly state when to use this tool over alternatives like ft_create_arkit_shapes or ft_combine_shape_keys. No exclusions or when-not-to-use guidance is provided.

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