optics_raytrace

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

With no annotations, the description carries the full burden and does well: it discloses the rayoptics wheel dependency, that failures return {ok:false, reason, install} instead of raising, and that results are gated against an exact oracle via oracle_max_dev_deg. It does not cover permissions, limits, or convergence caveats, so it falls short of a 5.

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?

Content is front-loaded (verb+resource first, then dependency behavior, then parameters and returns). It is dense and parenthetical-heavy but nearly every sentence carries distinct information, with little waste.

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 4-param tool with no output schema and no annotations, the description covers purpose, dependency/failure behavior, all defaulted parameters, and the returned dict fields (efficiency, tir_fraction, exit_distribution, hotspot_locations, etc.). Gaps are minor rather than blocking.

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 compensate, and it largely does: it defines n_refractive (n2, default PMMA 1.49062), enumerates source_config kinds with their fields, and lists model keys (n1 default air, absorption, target_half_angle_deg). n_rays is only inferable from the return-field list, leaving one parameter under-explained.

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 states a precise verb+resource: 'Ray-trace a bundle through a dielectric optical model with rayoptics'. It also implicitly differentiates itself from geometry-bound siblings like optics_solid_trace by noting it 'needs no FreeCAD geometry' and is 'asynchronous-free', so an agent can place it without opening a 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?

It conveys context ('needs no FreeCAD geometry', dependency on the optics extra, async-free), which implies when this is the right tool, but it never names an alternative or states an explicit when-not condition. Usage must be inferred rather than read.

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