add_feature_during_print

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

With no annotations, the description carries the full burden. It does disclose that a UI stage opens and that oversized meshes are decimated, but for a tool that alters G-code mid-print it says nothing about whether the printer is commanded, whether output writes to disk (output_dir), whether the original file is preserved, or what happens on failure. The marketing sentence about Free-vs-Pro features adds no behavioral information.

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 useful content (one sentence of purpose) is buried under a subscription upsell with a pricing URL and a duplicated INLINE 3D STAGE section that repeats what the first paragraph already said about the stage and browser link. Roughly half the text earns no place in a tool definition and dilutes the front-loaded signal.

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 22-parameter, no-annotation, no-output-schema tool that mutates a live print, the description leaves far too much unsaid: no return value description, no error or failure behavior, no explanation of the AMS/filament matching parameters, and no statement of what the print does while the slice runs. It is complete only about licensing and the UI stage.

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?

Twenty-two parameters with only 73% schema coverage, and most of that coverage is placeholder text like 'Default: 65.' or 'Default: ""'. Required parameters feature, gcode_path, current_layer, plus placement, printer_bed_size, source_3mf_path, target_ams_slot and require_ams_match are undocumented in both schema and description. The description mentions 'pause_z' but not that this maps to the optional pause_z_mm parameter, and adds no field semantics 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 line names a specific action and target: slice a new mesh at a Z pause and resume the print. It does not distinguish it from the closely named sibling add_feature_during_print_fleet, nor from decorate_during_print or deboss_during_print, so an agent must infer which mid-print mutation applies. The parenthetical '(Pro)' is the only disambiguating signal.

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 only stated precondition is licensing ('Requires Kiln Pro'), which does function as a usage gate but is a commercial one, not a task one. Nothing says when to choose this over the fleet variant or over splice_mesh_at_z, and nothing states the obvious prerequisite that a print must already be in progress and paused. Usage is implied rather than specified.

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