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

The description mentions AI-generated rewriting, implying non-deterministic results, but does not elaborate on behavior like potential variability or credit consumption. Annotations already indicate non-idempotency; the description adds little beyond purpose.

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 captures the tool's action and provides illustrative examples without redundancy. It is well-structured and front-loaded with the core functionality.

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 simple with two parameters and no output schema. The description covers the intended transformation but does not explicitly state the return value (rewritten text). However, the absence is minor given the tool's straightforward nature.

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 coverage is 100%, but the description adds valuable examples for the 'instruction' parameter (e.g., 'make it more professional', 'translate to Spanish'), which clarifies usage beyond the schema's generic description. This extra context raises the score above baseline.

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 rewrites or rephrases text using AI, with specific examples like formalizing, translating, or summarizing. It distinguishes this from sibling tools that send, compose, or edit messages, making the purpose unambiguous.

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 provides clear examples of when to use (e.g., formalizing, translating, summarizing) but does not explicitly state when not to use or mention alternatives. While the context is clear, the lack of exclusions or comparisons to similar tools leaves minor room for ambiguity.

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