dimension_diametric

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

Annotations only declare readOnlyHint=false; the description adds real value by stating the side-effect ('Adds diametric DIMENSION entity'), that the active dimension style is used, and that leader length must be positive. Missing only return/error behavior, which the output schema partly covers.

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?

Three short, front-loaded lines: purpose first, then side-effects, then disambiguation. No filler, and each line adds distinct information.

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?

With an output schema present and annotations covering the mutation flag, the description supplies the remaining essentials: side effect, style source, and sibling routing. Only minor gaps around failure modes and required drawing context remain.

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 100%, so the baseline is 3; the description nudges above it by clarifying the geometry model (center/chord pair defining the diameter) and the 'positive' constraint on leader_length that the schema does not state. Layer defaulting is left to the schema, which is fine.

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?

States a specific verb and resource ('Create a typed diametric dimension') plus the geometry inputs (center/chord, leader length) and the style source. It also explicitly separates itself from dimension_radial, so an agent can distinguish it from the radial sibling without opening schemas.

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 disambiguation line gives a concrete routing rule: use this for diameter display, use dimension_radial for arc radii. That is clear context-setting, though it does not state broader preconditions (e.g., an active drawing must exist, dimension style must be configured).

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