evaluate_expression

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

Describes the tool as a read-only query ('reading state'), and the examples show it returns values without side effects. No annotations provided, so the description carries the full burden; it covers the behavioral traits well but could mention error handling or allowed expression scope.

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 ~80 words, front-loaded with purpose and usage, then examples. Every sentence is meaningful and earns its place. Well-structured for quick understanding.

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 simplicity (one parameter, no output schema) and context signals, the description is sufficiently complete. It covers purpose, usage, examples, and what not to do. Could add more on return value format or error behavior but is adequate.

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 provides description for the only parameter (expression) with a basic example. The description adds value by clarifying that the expression should be a single value/call and not a full script, and provides multiple concrete examples, going beyond schema.

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 it evaluates a simple ExtendScript expression and returns its value, specifying it's for quick queries like checking properties or counts. Distinguishes from full scripts via 'NOT a full script' and provides examples, setting it apart from sibling tools like execute_extendscript.

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 says use for quick queries and not for full scripts, giving clear context. Does not name alternative tools directly but the contrast with 'full script' implies there is a separate tool for more complex scripting, providing good guidance.

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