plan_supports

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

With no annotations, the description carries the full burden. It usefully discloses that the tool is gated behind Kiln Pro and that output includes a rationale ("and why"), but it never says whether it needs an active printer profile, whether it mutates anything, how long it takes, or what the response contains. Half the text is marketing rather than behavioral disclosure.

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 first sentence is tight and front-loaded, which is the right structure. However, two of the four lines are subscription upsell plus a marketing URL with tracking parameters, which pads the definition without helping an agent decide or invoke.

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 6-parameter tool with no annotations and no output schema, the definition should clarify the return shape (a structured plan? G-code? recommendations?) — it only hints at "what the slicer should do... and why." Combined with thin parameter coverage and no usage routing, an agent would struggle to call this correctly versus sibling support-estimation tools.

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 33%, with the two documented fields described only as defaults ("PLA", "0.2"). The description adds nothing about input_path format (mesh, 3MF, relative or absolute), what printer_id changes, how nozzle_diameter interacts with layer_height, or what second_material is for (soluble/interface supports). The undocumented majority is not compensated for anywhere.

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 opening sentence gives a specific verb and resource with scope: "Plan the supports for one part: what the slicer should do under each overhang, and why." It implies the output is a per-overhang support strategy with rationale. It does not distinguish itself from close siblings like estimate_supports or estimate_support_material, so it stops short of a 5.

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?

There is no statement of when to use this versus estimate_supports, estimate_support_material, generate_adaptive_slicing_plan, or slice_and_estimate, despite many overlapping siblings. The only conditional content is a tier gate ("Requires Kiln Pro"), which is not usage guidance about the task itself.

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