group_layers

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

Annotations already declare readOnlyHint=false and openWorldHint=false, so the mutation and closed-world nature are covered. The description adds real behavioral value by stating the grouping is a single undoable operation, which tells the agent it is atomic with respect to undo history. It omits what happens on failure, whether partial grouping is possible, and what identity the resulting group has.

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?

A single front-loaded sentence with no filler; the atomicity guarantee is highlighted rather than buried. It is arguably too sparse for a four-parameter mutation tool, but nothing present is wasteful.

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 mutation tool with no output schema, four parameters, and zero schema description coverage, the definition is thin. It does not describe the return value (e.g., new group id), the concurrency contract implied by expectedRevision, or failure behavior, leaving the agent to guess on invocation-critical 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?

With four parameters and 0% schema description coverage, the description must carry parameter meaning but only restates 'layer ids'. The concurrency parameters requestId, sessionId, and expectedRevision are entirely undocumented, and expectedRevision in particular is a semantically loaded field (optimistic concurrency) that an agent cannot infer.

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 ('Group') and resource ('selected layer ids'), so the operation is immediately identifiable. It does not name or differentiate itself from the obvious sibling ungroup_layer, but the verb/resource pair is unambiguous enough that an agent can select it.

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?

No when-to-use guidance, no prerequisites, and no mention of alternatives such as ungroup_layer or array_layer. The description does not say whether the layers must share a parent, whether ordering matters, or when grouping is preferable to other structural operations.

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