add_group_layer

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

Annotations already declare readOnly=false, destructive=false, and openWorld=false, so the safety profile is covered. The description adds useful behavioral detail beyond that: the layer is created empty, it sits on top of the stack, and it acts as a nesting container for subsequent add_layer/move_layer calls.

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?

Two sentences, zero filler, with the core action front-loaded ahead of the follow-up nesting hint. Every clause earns its place.

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 simple two-parameter mutation whose safety profile is covered by annotations, the description is adequate to call the tool correctly, but the complete absence of filename/name semantics is a real gap and there is no output schema to lean on.

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 0% for both required parameters (filename, name), and the description says nothing about either. An agent gets no guidance on whether filename is the sprite file path or what name refers to, so the description fails to compensate for the coverage gap.

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 ('Add a new (empty) group layer') plus placement ('on top of the stack'). It distinguishes itself from the sibling add_layer by clarifying that this creates a container that other layers are nested into rather than a drawable layer.

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?

Gives clear follow-up context by naming the exact sibling calls (add_layer(group=...) or move_layer(group=...)) used to populate the new group. It does not state when to prefer a group layer over other structuring approaches or any exclusions, so it falls short of full when/when-not guidance.

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