figma_eval

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

Discloses that code runs in async IIFE, last expression is result, nodes returned as stubs, and each call is one undo step. No annotations present, so description carries full burden; covers major behavioral traits but omits error handling.

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?

Concise at ~100 words, well-structured with clear sections: purpose, execution model, usage guidance. No redundant 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?

Covers execution model, result format, and usage context well. Lacks mention of error behavior or security implications, but given no annotations or output schema, this is fairly 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?

Schema has two params with 50% coverage. Description adds context for 'code' (JavaScript in async IIFE) but does not explain 'timeoutMs' behavior, partially compensating for schema gaps.

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?

Clearly states 'Execute JavaScript inside the connected Figma plugin sandbox' with specific verb and resource. Distinguishes from siblings by suggesting structured tools for common operations.

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 advises using structured tools for common operations and reaching for eval when they don't cover the need. Also describes execution context (async IIFE, await, return).

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