join_meshes

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

The annotation provides destructiveHint=true, and the description adds specific context by stating 'Destroys source objects' and 'The first object becomes the active/target.' This goes beyond the generic annotation by clarifying exactly what is destroyed and how the target is determined.

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 description is two sentences long, front-loads the core action, and contains no irrelevant information. Every sentence adds meaningful context.

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 has one simple parameter and an output schema, so the description covers the essential behavior: joining geometry and destroying sources. It does not mention prerequisites like existing objects or type restrictions, but for a basic mesh operation this is acceptable.

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?

The schema provides no parameter descriptions (coverage 0%), so the description carries the burden. It implies 'objects' is a list of mesh objects and that ordering matters (the first is the target). However, it does not specify whether these are object names, IDs, or paths.

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 clearly states the action ('Join multiple mesh objects into one') and specifies the resource (mesh objects). It also notes the first object becomes the active/target, which is a specific behavioral detail. This distinguishes the tool from sibling operations like separate_mesh.

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?

The description indicates what the tool does but does not provide explicit when-to-use or alternative guidance. It implies you should use it when you want to merge mesh objects, but no comparison with other tools is given.

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