krita_set_selection

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

Annotations already mark destructiveHint=true and readOnlyHint=false. The description adds the important caveat 'No guaranteed undo transaction' and the canvas/16MP bounds constraint, giving the agent a clear risk warning beyond the annotations.

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 sentences, each with a distinct purpose: operation, shape-specific requirements, and constraints/warning. No filler or repetition.

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?

The description covers operation, shape conditions, bounds constraints, and undo caveat, but omits the effect of each mode (beyond a vague 'combine'), error behavior when bounds are exceeded, and any operation/return semantics (despite a required operation_id and no output schema). Thus adequate but not complete.

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 description must carry parameter semantics. It clarifies that rectangle uses x/y/width/height and polygon uses 3–256 integer points, which is helpful. However, it doesn't explain the mode values (add/subtract/intersect), coordinate system, or how points map to [x,y] pairs, leaving gaps.

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 ('Replace or combine') and resource ('the selection'), and specifies shapes (rectangle/polygon) and units (image pixels). However, it doesn't explicitly differentiate from sibling krita_modify_selection or mention the mode parameter, leaving some ambiguity about what 'combine' covers.

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 guidance on when to use this tool versus the sibling krita_modify_selection or krita_clear_selection. It describes how to specify shapes and constraints, but does not address alternatives or prerequisites such as an active document or how to select a mode.

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