Get bounding box

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the non-mutating, local-only profile is covered. The description adds the set of returned measurements, which is useful context, but says nothing about coordinate space behavior beyond the schema or about how the box is computed.

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 tight sentences, zero waste, with the return contents front-loaded before the use case. 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?

With no output schema, the description usefully enumerates the returned fields, which is the key piece an agent needs. It leaves the world vs. local coordinate behavior to the schema's worldSpace parameter, a minor gap for an otherwise simple two-parameter read tool.

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 both parameters (layerId with example id and pointer to cavalry_list_layers, and worldSpace with its default) are fully documented in the schema. The description adds no meaning beyond that, so the baseline 3 applies.

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 ("Return") and resource ("a layer's bounding box") and enumerates the exact components returned (x, y, width, height, centre, left/right/top/bottom). No sibling tool returns a bounding box, so an agent can route to it unambiguously without opening the schema.

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 intended contexts: laying out, aligning, and checking that layers fit inside the composition. It does not name an alternative tool or state when not to use it, so it stops 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.