nx_create_expression

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

With no annotations, the description carries the full behavioral burden. It indicates a write operation ('Create') but does not disclose what happens on duplicate names, whether the operation can be undone, whether the expression drives geometry, or if a current work part is required. The 'current work part' phrase is the only behavioral context beyond the verb.

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?

A single front-loaded sentence with no filler. Every word contributes the core action, the resource, and the target part. It is appropriately concise for a simple tool.

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?

The tool is simple and the schema covers parameter types and constraints, so the description is nearly adequate. However, no annotations or output schema exist, and the description omits failure modes, duplicate-name behavior, and explicit prerequisites, leaving clear gaps.

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 should compensate. It only hints at the name parameter via 'named' and the value via 'expression'; it does not explain the name pattern, the numeric type, or the fixed mm unit. The schema provides the raw constraints, but the description adds almost no semantic help.

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 names a specific action ('Create'), a specific resource ('named NX expression'), and a location ('current work part'). This is enough to distinguish it from sibling tools, which all target different NX objects such as parts, sketches, extrusions, holes, patterns, fillets, and chamfers.

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: the tool is for creating a named expression in the active part. There is no explicit when-to-use or when-not-to-use guidance and no mention of alternatives, but the context of 'current work part' provides a minimal boundary. It could be stronger by stating prerequisites such as having a work part open.

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