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

With readOnlyHint and openWorldHint already provided, the description adds important context: it discloses the limitation that it does not validate the signature chain itself. It also gives pricing details ($0.002 USDC per successful call via x402 on Base, Solana or Arc) and states failed calls are not charged, which is valuable behavioral information beyond annotations.

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 three efficient sentences, front-loading the core check before qualifying its limitations and pricing. Every sentence contributes useful information with no filler.

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 simple one-parameter schema, existing output schema, and annotations, the description covers what is checked, its limitation, and payment behavior. Nothing additional is needed for an agent to decide whether and how to call it.

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?

There is only one parameter and schema description coverage is 100%, so the schema already explains the domain input. The description adds little parameter-specific detail beyond establishing the domain as the subject of the check, which fits the baseline for fully documented schemas.

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 states a specific verb and resource: a DNSSEC check for a domain, naming the exact signals returned (DS record existence at the parent and AD flag from two named validating resolvers). This clearly distinguishes it from sibling DNS tools such as security_dns_records or security_dmarc_spf_dkim.

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?

Usage is clear from context: use this to verify whether a domain is signed and whether validating resolvers authenticate its A answer. It also clarifies the scope boundary that it reads resolver verdicts rather than validating the chain itself, though it does not explicitly name alternative tools for related DNS or TLS checks.

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