extract_variants

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

The description uses the verb 'Reads,' implying a read-only operation, and lists the return data. However, it does not disclose potential failure modes (e.g., non-component-set nodes), rate limits, or permissions beyond what the schema already provides. With no annotations, the description carries the full burden but stays minimal.

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?

The description is a single sentence that efficiently front-loads the action and resource, then enumerates the return content. There is no fluff or repetition, and it remains appropriately sized despite listing multiple data categories.

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?

Given the absence of an output schema and annotations, the description provides a solid overview of what the tool returns. It could mention edge cases or usage constraints, but the combination of the clear verb, resource type, and output fields is sufficient for most use cases.

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?

All three parameters have descriptions in the schema (100% coverage), and the tool description does not add extra meaning beyond mentioning 'component set,' which the schema already includes. The description adds no additional parameter context, so the baseline of 3 is appropriate.

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 clearly states the tool reads a Figma component set and returns structured variant data, with a specific list of data types (parsed variant properties, dimensions, layout details, fills, typography). This distinguishes it from sibling extraction tools like extract_design_tokens or extract_flows.

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 implies usage for component sets but does not explicitly state when to use this tool over alternatives, nor does it mention exclusions or alternative tools. The context is clear but lacks direct guidance on when not to use it.

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