validate_uuid

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

No annotations are provided, so the description carries the full burden. It discloses the exact validation behavior, the version detection logic (v1/v3/v4/v5), and enumerates all return keys including the surprising cost_usd field. This is comprehensive for a simple validation utility, though it could mention error behavior more explicitly.

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 uses a compact docstring structure with purpose, args, and returns. Every line adds useful information—the format check, version detection, example input, and return key list—with no filler or unnecessary repetition.

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?

Despite having no output schema or annotations, the description is sufficient for an agent to invoke the tool correctly and interpret results. It covers input format, validation behavior, and all return fields; even the unexpected cost_usd key is named, making the tool's behavior predictable.

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 only declares a required string property named uuid with no description (0% coverage). The description compensates by explaining the parameter is a UUID string and providing a concrete example, which adds meaning the schema lacks.

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 opens with a specific action and resource: 'Validate a UUID string and extract its metadata.' It then pinpoints the standard UUID format and version detection, which clearly differentiates it from sibling validation tools like validate_domain or validate_vat.

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 when to use the tool—whenever a UUID needs validation or metadata extraction—but it does not explicitly state when not to use it, mention prerequisites, or name alternatives. The scope is clear, but exclusionary guidance is absent.

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