Group instances

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

Annotations contain only a title, so the description must carry the behavioral burden. It does add one meaningful behavioral trait—no individual mates are created—but it doesn't disclose whether this mutates the assembly feature tree, whether it's reversible, or what effect grouping has on transforms. This is a meaningful gap for a mutating 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?

The description is one short, front-loaded sentence with no filler. Every word contributes to the core meaning, and it avoids restating schema details unnecessarily.

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 schema provides strong coverage of required parameters, and the operation is conceptually simple. However, with no annotations and no output schema, the description doesn't fully explain side effects or what an agent should expect after grouping. It is sufficient for basic invocation but leaves important operational context implicit.

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 100%, and each parameter already has a clear description in the schema. The tool description doesn't add parameter-level detail, so the baseline of 3 is appropriate. It offers no extra guidance on how to format occurrence IDs or how they relate to assembly instances.

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 uses a specific verb and resource: locking instances together, rather than simply restating the title. It also draws a clear distinction from mating tools by saying 'without individual mates,' which helps an agent tell it apart from assembly_mate. It stops short of 5 because 'lock' is somewhat jargony and doesn't explicitly say this creates a Group feature.

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 phrase 'without individual mates' implies the main use case: grouping instances when individual mates are not desired. However, it doesn't explicitly name alternatives or provide when-not-to-use guidance, and the sibling list contains several assembly tools that could overlap with this operation.

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