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

Annotations only say readOnly/openWorld=false; the description adds substantial behaviour beyond that — mesh-refined J and shear areas iterated to 0.5% convergence with a converged flag, composite handling via STIFF and STIFF_SUM per construction stage, and CIVIL-specific result naming. This is exactly the kind of solver semantics an agent could not infer from schema or annotations.

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?

Front-loaded with the core purpose and outputs, no filler sentences, and the convergence guarantee appears early. It is dense to the point of being hard to scan in one pass, which keeps it just short of top marks.

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?

With no output schema, the description takes on the burden of explaining return values and does so — result names, units, composite variants, and the converged flag. Combined with its statement that no model is required, an agent has everything needed to call it correctly.

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 100% and the nested section schema is extremely detailed, so parameter semantics are already carried by structured data. The description adds only a cross-reference ('Same section input as section_preview') and the note that results are in the section's units, which is marginal additional value.

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 resource and verb — computing the full CIVIL NX property set of a section — and enumerates the quantities produced (area, centroid, second moments, extreme fibres, perimeters, J, shear areas). It also distinguishes itself implicitly from section_preview by noting the shared input but differing output, so an agent can tell them apart.

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?

Gives a clear usage context: 'Needs no model' and 'Same section input as section_preview', which implies this is the compute counterpart to the preview tool. It stops short of explicit when-not guidance or naming section_read/section_write as alternatives, so it is clear but not fully routing.

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