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

Goes well beyond the annotations (destructiveHint=true, readOnlyHint=false) by disclosing that it refuses unconverged results, that an id collision writes nothing and reports how many elements use the id, that units are read from the model at write time, and that it reads back and compares every value after writing. The property/drawing approval workflow adds real operational context. Only the response payload shape (what the comparison result looks like) is left implicit.

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 critical gating information (preview-by-default, apply+hash, destructive replace) is front-loaded and every clause is actionable. It is dense and semicolon-heavy, with a couple of redundancies against the schema, but nothing is padding.

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 heavily nested schema with no output schema and four safety annotations, the description covers preconditions (open model, units at write time), the preview/approval protocol, collision handling, destroyed state on replace, and the undo path. An agent has everything needed to call it safely without opening the schema first.

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 100%, so the baseline is 3; the description still adds value by pointing to section_preview as the identical input shape and by highlighting that id defaults to the next free section id and that confirmPlanHash binds the write to the approved plan. Some statements (id default, replaceExisting destructive) restate schema text.

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 and resource — writes a section into the open CIVIL NX model — and ties it to a concrete behavioural reference (Section Designer's Write button), naming the write variants (VALUE/GEN, PSC/VALU, COMPOSITE-GEN). It is clearly separable from section_preview (which only draws) and section_write_undo (which reverses).

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 explicit when/when-not rules: previews by default, requires apply:true plus confirmPlanHash to write, requires replaceExisting:true (and user agreement) to overwrite a taken id, and directs the agent to show section_preview and section_properties for approval first. It also names the reversal path (section_write_undo).

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