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

Beyond the readOnlyHint and idempotent annotations, the description discloses that calling this tool costs $0.01 USDC on Base or Solana and that it normalizes via ENSIP-15 before hashing. This payment side effect and processing detail are genuinely useful, though the return format is not described.

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 compact and free of verbose filler, but it is a sentence fragment and opens with the payment detail rather than the core function. Reordering to state 'Computes ENS namehash and label hashes with ENSIP-15 normalization' would be more effective.

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 one-parameter, read-only, idempotent tool, the description covers the cost and main behaviors. However, there is no output schema and the description never states the result shape or exactly how namehash/label hashes are returned, leaving a small but real gap for an agent.

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?

With 0% schema description coverage, the description carries the burden, but it only implies that the single 'name' parameter is an ENS name. The reference to ENSIP-15 normalization adds context that the input will be normalized, yet there is no explicit format, example, or statement of what values are valid.

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 identifies the exact computation — ENSIP-15 normalization plus ENS namehash and label hashes — and the 'ens_namehash' name makes the resource clear. However, there is no explicit verb like 'compute' or 'return', and it does not contrast with generic hashing siblings such as keccak256.

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 provides no guidance on when to choose this tool over hash_encode, keccak256, or resolve, nor does it state conditions or exclusions. The only implied use case is deriving ENS namehash values, which the reader must infer from the tool name.

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