reverse_resolve_ens

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

Annotations already indicate readOnlyHint and idempotentHint. The description adds that it returns null if no primary name is set, which is useful behavioral detail. No contradictions, but additional traits like network dependency or error handling are omitted.

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 a single concise sentence that includes the action and return behavior. It is front-loaded and contains no extraneous information, though it could slightly expand on address formats without losing conciseness.

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 simple lookup without output schema, the description mentions the return value (null if unset). However, it lacks context on supported networks, potential errors, and assumes the agent knows ENS mechanics. It is adequate but not thorough.

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 coverage, the description must elaborate on the parameter. It says 'Ethereum address' but the schema allows three patterns, only one of which is Ethereum. This adds partial meaning but is inaccurate for the other formats and does not explain their purpose or validity.

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 reverse-resolves an Ethereum address to its primary ENS name, distinguishing it from forward resolution (e.g., resolve_ens_name). However, it mentions only 'Ethereum address' while the input schema includes patterns for non-Ethereum addresses (T and base58), causing slight ambiguity.

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 does not explicitly state when to use this tool vs alternatives. It implies reverse resolution but lacks guidance on prerequisites, network context, or exclusions. The sibling `resolve_ens_name` is not mentioned, leaving the agent to infer the differentiation.

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