blender_shapekeys

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

With no annotations, the description must disclose behavioral traits. It only lists handled tasks without mentioning side effects (e.g., modifying mesh data, potential destruction of existing shape keys) or required permissions/context (e.g., active mesh must have shape keys). This is insufficient for safe invocation.

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 sentences efficiently convey purpose and scope. First sentence states primary function, second enumerates key use cases. No redundancy or filler, earning top score.

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 14 parameters, output schema presence, and lack of annotations, the description provides a reasonable overview. It covers the main operations implicitly. However, it could be more precise about VRM compliance details and output structure. Still, it is mostly sufficient.

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 each parameter is documented. The tool description adds a high-level overview but does not enhance parameter understanding beyond the schema. Baseline 3 is appropriate per rubric.

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 explicitly sets the tool scope to 'shape key management for facial animation and VRM avatars' and lists specific capabilities like viseme creation, blink animations, facial expressions, and VRM compliance. This clearly distinguishes it from sibling tools like blender_rigging or blender_animation.

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 implies usage for facial animation and VRM work but provides no explicit guidance on when to use this tool versus alternatives (e.g., blender_animation for rigged animation) or situations to avoid. It lacks when-not-to-use or prerequisite notes.

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