Overview

Ethereum Name Service (ENS) maps human-readable names to Ethereum addresses. Instead of your agent being identified as 0x7a3f8B2c...91D4, it becomes polybot.eth. ENS names resolve to addresses, addresses resolve back to names, and the name can carry on-chain metadata that describes the agent.

For prediction market agent builders, ENS serves two purposes. First, discoverability: a marketplace listing for arb-hunter.eth is immediately more memorable and trustworthy than a hex string. Second, metadata: ENS text records let you attach a description, website URL, avatar, and social links directly to the name, readable by any ENS-aware application.

ENS is already part of the Coinbase Agentic Wallet workflow. When you run npx awal send 5 recipient.eth, the CLI resolves the ENS name to an address before executing the transfer. Any agent with a Coinbase wallet can send funds to an ENS name, and any agent with an ENS name can receive funds by sharing a readable identifier instead of a hex address.

Key Features

Human-readable addresses — myagent.eth replaces 0x7a3f8B2c4E...91D4 everywhere: marketplace listings, transaction records, cross-agent communication, and payment requests. The name resolves to the underlying address automatically in any ENS-compatible wallet, dApp, or CLI tool.

Text records — ENS names support arbitrary key-value text records stored on-chain. Standard keys include description, url, avatar, com.twitter, and com.github. Agent builders can use these to publish machine-readable metadata: strategy type, supported markets, API endpoint, or a link to attestation records. Any application that resolves the ENS name can also read these records.

Subnames — A single ENS name can have unlimited subnames. If your organization runs multiple agents, register myorg.eth and create arb.myorg.eth, sentiment.myorg.eth, and market-maker.myorg.eth. Subnames inherit the parent’s ownership and can be managed programmatically. This creates a natural hierarchy for multi-agent setups without registering multiple top-level names.

Reverse resolution — Given a wallet address, ENS can return the associated name (if one is set). This enables services to display human-readable names in transaction logs, leaderboards, and marketplace interfaces. When a marketplace shows that polybot.eth has a 73% win rate, it’s using reverse resolution to translate the address back to a name.

Cross-chain support — While ENS names are registered on Ethereum mainnet, resolution works across L2s and other chains through CCIP-Read (EIP-3668). An agent operating on Base can still be identified by its .eth name, and applications can resolve that name to the agent’s Base address.

Agent-Friendliness

AspectRating
JavaScript SDKExcellent — ensjs with full TypeScript support
ethers.js supportNative — provider.resolveName() and provider.lookupAddress()
viem supportNative — built-in ENS resolution functions
Coinbase CLIIntegrated — npx awal send accepts ENS names
DocumentationExcellent — docs.ens.domains with tutorials and API reference
Text record supportYes — read and write arbitrary metadata on-chain

Pricing

ENS name registration costs vary by name length: 3-character names cost $640/year, 4-character names cost $160/year, and 5+ character names cost $5/year. Registration and renewal transactions require Ethereum mainnet gas fees. Subnames can be created under a parent name for only the gas cost. Text record updates also require gas. L2 resolution via CCIP-Read incurs no additional cost beyond the initial mainnet registration.

Best For

Agent discoverability and human-readable identification in marketplaces, leaderboards, and cross-agent interactions. If your agent will be publicly listed, referenced in transactions, or needs a memorable identity beyond a hex address, an ENS name makes it findable and recognizable. Especially valuable for multi-agent organizations using subnames.