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

Annotations already cover read-only, idempotent, non-destructive and closed-world, so safety is settled. The description adds real behavioral context beyond that: the result is a deterministic stepper-math derivation, it is filtered to what suits the nozzle, and it discloses the default configuration and resulting step size (0.04 mm). It stops short of saying what the returned value looks like.

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?

Two dense sentences, front-loaded with the action and the physical model, followed by the concrete default configuration. Nothing is repeated from the schema or annotations and there is no filler.

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 six-parameter, zero-coverage, no-output-schema tool, the description is adequate but incomplete: it omits max_layer_height_mm entirely and never indicates the shape of the result (a set/list of candidate layer heights?), which matters for a computation tool whose output the agent must interpret.

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 description coverage is 0%, so the description must carry the burden, and it partially does: it explains the roles of step angle, microstepping, lead-screw pitch and starts, and pins their defaults (1.8°, 1/16, T8 2 mm × 4 starts). However, max_layer_height_mm is never mentioned, and units/relationships for the remaining parameters are left to the parameter names.

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 ('Compute') and a specific resource ('Z-axis magic number layer heights for a printer'), and names the exact inputs the result derives from (step angle, microstepping, lead-screw pitch/starts). This is clearly distinguishable from the sibling calculators (filament usage, print cost, volumetric flow) without opening any schema.

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?

Usage is implied rather than stated: the description tells the agent the defaults match 'most Ender/Prusa-style printers', which is a usable hint, but there is no explicit when-to-use, when-not-to-use, or comparison against the sibling calculate_* tools. An agent must infer the call context.

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