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

Annotations already cover safety (readOnly, idempotent, non-destructive), and the description adds real behavioral context beyond them: each record is returned with its TTL, NXDOMAIN is returned for missing names, no API key is required, and payment/auth mechanics (x402 on Base, x-credit-token header, 1 free call/day) are disclosed. Only the 'Not financial advice' line is thematic noise rather than behavioral signal.

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 purpose and required input are front-loaded, which is good, but the middle is padded with promotional copy ('The DNS commodity agents call constantly…', 'served at the sub-cent floor', 'Not financial advice') that does not help an agent invoke the tool. Sizing is moderate but several clauses do not earn their place.

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?

With only two parameters, full schema coverage, and an output schema present, the bar for description completeness is low, and the description still adds return details, error semantics (NXDOMAIN), and auth/pricing info. Nothing an agent needs in order to call it correctly appears to be missing.

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 description coverage is 100%, so the schema already documents both parameters including the default for type. The description repeats 'Pass name= and type= (default A)' without adding syntax, format, or constraint detail beyond the schema, which is the expected baseline-3 outcome when the schema carries the load.

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 ('Resolve DNS records for a domain via Cloudflare DNS-over-HTTPS') and enumerates the record types supported, so an agent knows exactly what the tool produces. It does not, however, distinguish itself from nearby siblings such as domain_check, ssl_check, or ens_resolve, so it stops short of a 5.

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 only implied via 'infra, email and domain checks,' which suggests contexts but never states when to use this tool versus domain_check or ens_resolve. There are no explicit exclusions or named alternatives, leaving the routing decision to inference.

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