Group Objects

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

Annotations cover the safety profile (readOnly=false, destructive=false, idempotent=false), so the description is free to add operational context — and it does, disclosing the stacking-order semantics and that execution happens in background mode without invoking Computer Use. It stops short of saying what happens to the source objects' layer membership or whether a new group object is returned.

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?

Three tight sentences with the core action front-loaded and no filler. The ordering sentence is mildly redundant with the schema, but the background-mode caveat is genuinely load-bearing context for an agent choosing between this and run_script.

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, the description covers ordering and execution mode but omits what the caller gets back (a new group UUID?) and any side effects on layer membership of the grouped objects. Adequate but with a clear gap for a write operation.

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%, so the ordering rule and the clipped/mask behavior are already documented in the schema. The description's ordering sentence largely restates the uuids schema text, adding no new syntax or constraints beyond it. Baseline 3 applies when the schema does the heavy lifting.

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 ('Group multiple objects into a single group'), which is unambiguous. It does not explicitly contrast itself with the nearest siblings (ungroup_objects, duplicate_objects, set_z_order), though the name makes the inverse relationship obvious.

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 and no prerequisites are given. It never says how this differs from set_z_order, duplicate_objects, or manage_layers, nor does it say what state the objects must be in (selected, same layer, ungrouped) before calling.

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