Create star

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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so safety/idempotency is covered structurally. The description adds a genuine behavioral trait not in the annotations: platform support (verified in Design, unverified in FigJam/Slides). It says nothing about what node is returned or how conflicts are handled beyond what idempotencyKey already documents in the schema.

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 dense sentences, front-loaded with the shape semantics before use cases and platform notes. Every clause carries information; no filler or repetition of the tool name.

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 15-parameter mutation tool with no output schema and an openEnded nested sizing object, the description covers purpose, key geometry params, and editor constraints but leaves most parameters and the return shape undocumented. Adequate minimum viable context, with visible gaps.

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 coverage is only 47% across 15 parameters, so the description would need to compensate more. It does add real interpretation for innerRadius (low = spiky, near 1 = polygon) and pointCount (spikes), which goes beyond the terse schema defaults, but x, y, fill, stroke, name, parentId, cornerRadius, strokeWeight, and sizing get no descriptive support.

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 states the resource precisely ('a star or burst') and defines its two defining parameters (pointCount spikes, innerRadius 0–1), which implicitly separates it from the sibling figma_create_polygon ('near 1 = almost a polygon'). The verb is carried only by the name/title, so it is clear but not fully self-contained.

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?

It supplies concrete use cases (rating stars, sale bursts, sparkles, decorative shapes) and an editor-compatibility caveat ('Editors: Design; unverified: FigJam, Slides'), which tells the agent when this tool is applicable. It does not name an explicit alternative for regular polygons, so it stops short of full routing guidance.

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