add_thread

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

Annotations already declare this is a mutating, destructive, non-idempotent, closed-world operation, so the safety profile is covered. The description adds marginally by naming the engine and promising "verified measurements and error evidence," hinting at post-operation validation. What exactly is modified or destroyed, and what permissions/preconditions are needed, is still unstated.

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?

Three short sentences, front-loaded with the action and engine, then units, then verification. Nothing is padded, though "Inspect verified measurements and error evidence" is slightly opaque phrasing that could be tightened into a concrete statement of what is returned.

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?

A 7-parameter destructive geometry-creation tool with no output schema and zero schema descriptions needs substantially more: the thread size vocabulary, the meaning of internal/length, and placement semantics are all missing. The units note is the only substantive help.

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 carries the full burden, and it only partially delivers: it clarifies that x_mm/y_mm/z_mm/length_mm are millimetres. The critical 'size' parameter (thread designation format such as "M6x1.0") and the 'internal' boolean (internal vs external thread) are left unexplained, as is whether coordinates are a start point or a face anchor.

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?

"Add thread" gives a specific verb plus the feature type, and "through the independent native SOLIDWORKS engine" signals that this creates real model geometry rather than a mock. It is reasonably distinguishable from generic siblings like add_box or add_hole, though it never says whether the thread is cosmetic/feature-based or whether it must attach to an existing face or hole.

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?

There is no when-to-use guidance at all: nothing says whether this should follow add_hole, add_hole_wizard, or add_counterbore_hole, nor whether a body or plane must already exist. The only implied context is the units statement, which is not a usage rule.

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