booltool_auto_union

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

With no annotations, the description carries the full burden and does well: it discloses that the target object is consumed and that the merge is destructive/irreversible, plus the fallback path (Bool Tool extension vs native modifier) and that a warning surfaces in the response. It stops short of stating preconditions such as object mode or active-object requirements, which matters for a destructive operation.

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?

Well front-loaded: the destructive verb leads, then the routing guidance, then Args/Returns. One sentence ('so parts don't float away from their bodies') is motivational filler rather than actionable information, keeping it just short of fully earned prose.

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 two-parameter destructive mesh tool with no annotations, the description covers purpose, default status, alternative routing, destruction semantics, fallback behavior, and the warning field. An output schema exists, so return values need no further detail; nothing an agent needs to invoke this correctly is missing.

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 0% – the schema only carries bare titles 'Object Name' and 'Target Name' – so the description must compensate, and it does by assigning roles: object_name is 'the main object to keep' and target_name is 'the object to merge into the main object.' That resolves the otherwise ambiguous direction of the merge, though it doesn't clarify what happens if names are invalid or objects are linked/duplicated.

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 ('Auto boolean union: merge two mesh objects into one') plus the key modifier ('destructively'). It also implicitly distinguishes itself from the sibling family (booltool_auto_difference/intersect/slice) by naming the operation type outright.

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?

Explicitly declares itself the default choice for a union and names the exact condition that selects the alternative: 'Use boolean_operation instead only when the cutter must stay editable as a modifier.' The when-to-use and the when-not-to-use are both present with the alternative named.

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