create_assembly

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

With no annotations, the description carries the load and does reasonably well: it discloses atomicity ('one transaction'), a side effect ('Creates the native joint group'), a hard failure condition ('Refuses parts already inside containers'), and non-persistence ('Does not save files'). It stops short of stating required permissions, what is returned, or what happens to the document on failure.

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?

Four short sentences, front-loaded with the core action and followed by constraints, with no filler. The telegraphic style borders on clipped but every sentence carries information.

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?

No output schema and no annotations, so the description must cover both behavior and parameters; it covers behavior well but leaves all three parameters undocumented, including format expectations for doc_name and the parts list. Adequate for the mutation semantics, incomplete for invocation details.

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% and the description only touches one parameter indirectly by qualifying parts as 'ROOT parts'. The required doc_name and the optional name (default 'Assembly') are left completely unexplained, so an agent has to infer their meaning from the field names alone.

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 ('Create a native FreeCAD Assembly') plus scope ('containing specified ROOT parts, preserving world poses'), which separates it from siblings like create_document or create_fixed_joint. It does not explicitly name a sibling it replaces, but the purpose is unambiguous.

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 precondition/exclusion ('Refuses parts already inside containers') and a scope limit ('Does not save files'), which are genuinely useful usage signals. However, it never says when to prefer this over alternatives such as create_fixed_joint or create_document, so the routing guidance is only implied.

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