add_cylinder

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

With no annotations provided, the description carries the full burden of disclosing behavior. It warns that the tool will 'update the JCAD document at the given jcad_path,' clearly indicating a write operation, and instructs the agent to first read the current state. It also mentions the return value as the document itself. This is transparent about the mutating nature, though it omits details on error handling or overwrite semantics.

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 structured into a one-line purpose, a parameter docstring, and a warning. It is not overly long, and every section adds necessary value given the lack of schema descriptions. The front-loading of purpose is effective, though the warning is slightly verbose with formatting whitespace.

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 9 parameters, no output schema, and no annotations, the description covers all parameters, the return value, and the prerequisite for usage. It explains the mutation behavior and points to get_current_cad_design for context. It could be more complete by specifying whether the cylinder is centered at position or how rotation axes relate to the shape, but overall it is sufficiently complete for a typical CAD manipulation tool.

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 input schema has zero parameter descriptions, so the description fully compensates by explaining each parameter in detail (name, radius, height, angle, color, position, rotation_axis, rotation_angle). It even clarifies angle semantics (0: no cylinder, 180: half, 360: full) and color format (hex or RGB float list). This goes well beyond the schema's bare properties and defaults.

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 'Add a cylinder to the document.' This is a specific verb and resource, and it distinguishes the tool from siblings like add_box, add_cone, add_sphere, and add_torus. The purpose is unambiguous.

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 does not explicitly mention alternatives, but it provides a key usage prerequisite: 'To understand the current state of the document, you MUST first use the get_current_cad_design tool.' This gives clear context on when to use the tool and emphasizes inspecting the document before mutation. However, it lacks explicit when-not-to-use or alternative recommendations.

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