add_group

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

With no annotations, the description carries the full burden. It discloses that the tool creates an element, returns its uuid, and explains rotation behavior. However, it does not mention potential errors (e.g., invalid parent), idempotency, or permissions, leaving moderate gaps for a creation tool.

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 front-loaded with the main action and efficiently explains key concepts in four sentences. The second sentence is somewhat lengthy but provides essential context; minor trimming could improve conciseness.

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 tool with 4 parameters, no required fields, and no output schema, the description explains creation, usage, and return value adequately. It lacks error handling details but is sufficient for an additive tool with simple semantics.

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?

The description adds meaningful usage hints beyond the schema: for origin (set to real joint), rotation (use to pose limbs), and parent (omit for root). The name parameter lacks description in both schema and description, keeping it from a perfect score.

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 tool adds a group/bone to the outliner, distinguishing it from sibling tools like add_cube by explaining that groups are used for animation and multi-axis rotation. The verb-resource pair is specific and the context differentiates it well.

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 strong guidance on when to use groups (for animation and free 3-axis rotation) versus cubes (single-axis rotation) and suggests nesting groups for compound angles. However, it does not explicitly address when not to use the tool or compare to the sibling add_groups (plural).

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