krita_paint_shape

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

Annotations already declare the tool as non-read-only, destructive, and idempotent. The description adds genuine behavioral detail beyond those flags: it restores brush context, waits for native completion, and instructs reuse of operation_id. These details help the agent understand side effects and async behavior without contradicting 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?

Four short sentences, each serving a distinct purpose: what the tool paints, prerequisites, behavior, and operation handling. The main action is front-loaded and there is no filler or redundant restating of schema fields.

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 14-parameter tool with no output schema, the description is unusually informative: it covers the deliverable, prerequisites, brush context restoration, completion semantics, and operation_id reuse. The main gaps are the exact meaning of 'native', coordinate conventions, and return behavior, but the essential call pipeline is well specified.

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 carries the burden of explaining parameters. It maps several key parameters to concepts: 'brush settings' for preset_id/size_px/opacity/color, 'solid foreground fill' for fill, and operation_id reuse. However, identifiers like instance_id, document_id, and node_id, plus coordinate semantics for x/y, are left implicit, so the coverage is incomplete.

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?

The description opens with a specific verb and resource: 'Paint one native rectangle/ellipse with explicit brush settings and optional solid foreground fill.' This clearly distinguishes the tool from sibling paint tools like krita_paint_line, krita_paint_path, and krita_paint_bezier_path, and from vector shape tools, without needing to open 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?

The description states concrete preconditions: active document, pixel brush, and no active selection. It also implies the intended use case—drawing a rectangle or ellipse—and gives an operational hint to reuse operation_id. It does not explicitly name alternatives, but the context is clear enough for an agent to decide when this tool is appropriate.

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