set_equation

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

With no annotations, the description carries the full behavioral burden. It discloses that the tool rebuilds and remeasures, persists a relation, and returns mass properties. This goes well beyond a generic 'sets an equation' statement. It does not cover invalid-equation handling or prerequisites, but the main side effects are transparent.

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?

Every sentence earns its place. The core action is front-loaded, followed by necessary syntax examples and one comparative note about persistence. There is no filler or repetition of schema fields.

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 one-string-parameter tool with no annotations and no output schema, the description is complete. It explains the parameter format, the side effects, the alternative tool, and the return value. Nothing essential is missing for an agent to select and invoke this tool correctly.

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 fully explain the lone parameter. It does: it provides exact SolidWorks equation syntax, multiple examples, global variable syntax, and how to link a dimension to a global variable. An agent can construct a valid equation string directly from the description.

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 uses a specific verb and resource: 'Add a global equation linking dimensions, then rebuild and remeasure.' It clearly distinguishes itself from set_dimension by stating that it 'Persists a relation (unlike set_dimension).' This is not a tautology and gives an agent a precise mental model of the action.

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 explicitly names set_dimension as the alternative and explains the key difference: set_equation persists a relation, set_dimension does not. It also implies the workflow (add equation, rebuild, remeasure), giving contextual guidance. It lacks a fuller when-not-to-use list, but the core routing decision is covered.

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