figma_get_library_variables

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

No annotations are provided, and the description offers minimal behavioral disclosure beyond the read action. It mentions token usage reduction but does not describe pagination, auth requirements, or error behavior, leaving the agent to infer operational traits.

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 two sentences with no redundancy; the first states the core function, the second offers practical filter advice. Every word earns its place with no filler.

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?

The tool is a simple read operation, but with no annotations and no output schema, the description should cover return format or pagination. It only hints at token usage reduction and does not explain what the response looks like, so it is adequate but not fully self-contained.

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?

The schema already documents limit, namePattern, and resolvedType with descriptions (75% coverage). The description adds the rationale for filtering to reduce token usage, which is useful, but it does not clarify collectionKey further or add formatting details beyond what the schema provides.

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 retrieves variables from a library collection by key, using the specific verb 'Get' and the resource 'variables from a library collection by key'. This distinguishes it from sibling tools like figma_get_variables or figma_get_library_collections.

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 when you have a collection key and want to filter variables, with the added note about reducing token usage. However, it does not explicitly compare to alternatives such as figma_get_variables or explain when not to use this tool, so guidance is present but not fully developed.

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