validate_tld

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

Without annotations, the description discloses that checks are against the IANA root-zone list, kept current, and returns valid:false for non-delegated TLDs. It does not discuss idempotency or side effects, but for a validation tool, these are sufficiently transparent.

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, front-loaded with 'USE THIS', and contains no extraneous words. Every part serves a purpose: examples, authoritative source, and expected return behavior.

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 tool has one parameter and no output schema, the description fully covers the input, process, and output. It explains what it validates, against which source, and what the result means, leaving no gaps.

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 tool description adds examples of TLDs to check but the parameter schema already fully describes the 'tld' parameter (with/without leading dot). Schema coverage is 100%, so the description provides marginal extra value beyond the 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?

The description clearly states the tool validates whether a top-level domain is real using the authoritative IANA root-zone list, providing specific examples like .zip and .corp. It distinguishes itself from siblings like validate_domain by focusing on TLDs alone.

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 explicitly advises 'USE THIS to check whether a top-level domain is real before trusting a domain or link — do NOT guess' which provides strong when-to-use guidance. However, it does not mention alternatives or specific when-not-to-use scenarios, though siblings like validate_domain imply a different scope.

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