Resolve an ENS name or Basename to an address, or reverse-resolve a 0x address to its name + avatar. Send { input }. Human-readable identity for agents. [x402 paid tool — price $0.003; POST /api/crypto/ens]
| Name | Required | Description | Default |
|---|---|---|---|
| input | Yes | An ENS/Basename (e.g. vitalik.eth) or a 0x address |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description discloses pricing ($0.003) and the HTTP method, but lacks details on idempotency, rate limits, or error handling. It adds value beyond schema but could be more transparent.
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 concise and front-loaded with the primary function. It includes pricing in brackets, which adds context without excess verbosity.
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?
Despite lacking an output schema, the description mentions possible outputs (address or name+avatar). For a simple tool with one parameter, it provides adequate context for an agent to use it correctly.
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% with a clear description of the 'input' parameter. The description repeats the usage (e.g., vitalik.eth or 0x address) but doesn't add new semantics beyond the schema.
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 resolves ENS/Basenames to addresses and reverse-resolves addresses to names+avatars. It uses specific verbs and distinguishes from sibling crypto 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?
The description implies usage for human-readable identity resolution with 'Human-readable identity for agents.' However, no explicit when-to-use or when-not-to-use guidance is provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.