select_rectangle

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

With no annotations at all, the description carries the full burden and discloses little beyond the parameter meanings. It does not state that the default "replace" operation discards any existing selection, whether the selection requires an active image, how out-of-bounds coordinates are handled, or whether the change is undoable; "Returns status dict" gives no shape or failure semantics for a state-mutating tool.

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 one-line purpose is front-loaded, then a compact bulleted parameter list with no filler. The trailing "Returns status dict" is terse but justified, and nothing in the description is redundant.

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 7-parameter, state-mutating selection tool with no annotations and no output schema, the description covers every parameter but omits interaction with pre-existing selections, prerequisite context (active image via image_index), and any return-value detail beyond the word "dict". It is enough to compose a call but not enough to predict its side effects.

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%, so the parameter list is the only source of meaning, and it does real work: it labels x/y as the top-left corner, defines width/height, enumerates the four operation values (which the schema does not declare as an enum), and explains feather units and all three defaults. The main gap is that pixel units, coordinate origin, and valid ranges for width/height are never stated.

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?

"Create a rectangular selection" names a specific verb and resource, and the parameter list makes clear it is a geometric region selection rather than a color- or state-based one. An agent can distinguish it from select_ellipse, select_by_color, and select_all by the shape implied in the first sentence, though no sibling is named explicitly.

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 description never says when to choose this over select_ellipse, select_by_color, select_all, or select_none, nor when a selection is a prerequisite for later tools like fill_selection or crop_to_selection. The operation parameter hints at combining modes but the agent is left to infer the routing decision.

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