Create polygon

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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=true, openWorldHint=false), so the description need not restate them. It adds useful editor-compatibility context that structured fields do not carry. However it says nothing about where the node lands (parentId/current page), what is returned, or what happens with an invalid parent, leaving gaps for a mutation 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?

Three dense fragments, no filler, and the core meaning (what shape, how the count maps, when to use it) comes first. The editor-compatibility note is placed last where it belongs. Nothing here could be cut without losing information.

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 mutation tool with no output schema and sub-half schema coverage, the description covers shape semantics and environment support but omits the return value, placement behavior (parentId vs current selection/page), and the practical role of idempotencyKey for retries. Annotations cover safety; the remaining operational gaps keep this at adequate rather than 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?

With only 43% schema description coverage across 14 parameters, the description is expected to compensate, and it partly does by mapping pointCount values to real shapes and pointing to figma_rotate_nodes for diamonds. But 13 of 14 parameters (fill, stroke, name, x/y, parentId, session, sizing, cornerRadius, strokeWeight) get no semantic help from the description; the schema carries the rest. Partial compensation only.

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 names the exact resource (a regular polygon) and enumerates concrete cases — triangle with pointCount 3, diamond with pointCount 4 plus figma_rotate_nodes — which is far more specific than the title 'Create polygon'. It implicitly separates the tool from sibling shape creators like figma_create_star, figma_create_ellipse and figma_create_rectangle, though it never names them. No explicit verb, but the intent (create a polygon node) is unmistakable.

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 use-case context ('Badges, play buttons, decorative geometry') plus an environment note that it is supported in Design and unverified in FigJam/Slides, which is real selection guidance for editor choice. It also cross-references figma_rotate_nodes for the diamond case. What is missing is any when-not-to-use statement versus figma_create_vector or figma_create_star.

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