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

With no annotations, the description carries the full burden and does disclose meaningful behavior: the $0.001 per-call price, the x402 payment model, and the fact that the purchase can complete inside the tool call. The 'forward-verified' qualifier also signals a trust semantic for reverse lookups. It still omits failure/error behavior, but the paid-call mechanics are well surfaced.

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?

One dense sentence followed by a short pricing clause; nothing is wasted and the dual-purpose lookup is front-loaded. Mildly long but every clause earns its 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?

For a two-parameter read tool with no output schema and no annotations, the description covers the return fields (address, owner, profile records, primary Basename) and the payment flow. Only edge-case behavior (unknown name, unset primary name) is 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 coverage is 100%, so the baseline is 3. The description echoes the schema's dual meaning for `q` and clarifies that the reverse direction returns the primary name specifically, but adds little syntax or format detail beyond what the parameter descriptions already state.

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 names a specific verb+resource and spells out both resolution directions: a Basename to address/owner/profile records, and an address to its forward-verified primary Basename. That is far more specific than the bare name 'basename', though it doesn't explicitly differentiate itself from nearby lookup tools.

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?

Two usage modes (forward and reverse lookup) are implied by the enumeration, so an agent can infer what inputs are appropriate. However there is no explicit when-to-use guidance, no mention of alternatives, and no note on what happens for unregistered names.

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