Apply style

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

Annotations cover the safety profile (readOnly=false, idempotent=true, destructive=false), and the description adds genuine behavior: per-item partial-success semantics ('one node failing does not fail the call'), the exact return shape, and editor support ('Design; unverified: FigJam, Slides'). It stops short of stating that applying a style replaces existing fills/strokes.

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?

A single dense paragraph where every clause carries routing or behavioral information; the core action is front-loaded before the alternatives and edge cases. No filler sentences.

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?

With no output schema, the description supplies the return contract (`{ updated, items: [{ id, ok, error? }] }`), the partial-failure rule, the style-source alternatives, and platform coverage — everything needed to call it correctly and interpret results.

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 83% schema coverage the baseline is 3, but the description adds real meaning beyond the enum: `type` defaults to fill and can be stroke when applying a paint style, and it explains the id-vs-name distinction for styleId/styleName. It does not touch `session` or `idempotencyKey`, which the schema already documents.

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 and resource (apply a local style to a node), enumerates the style kinds (paint, text, effect, grid), and clarifies the effect ('the node then follows the style'). It is readily distinguishable from siblings like figma_create_paint_style and figma_set_fills.

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?

Explicitly routes the agent: use figma_set_fills for a raw colour, figma_get_styles for local styles, and figma_get_design_context's `stylesUsed` id for library styles. It also states when `type` is needed (shared name across kinds, or paint-as-stroke with fill as default).

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