# Delx Address Checksum EVM

> Delx Address Checksum EVM is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-16).

Produces or validates an EIP-55 checksummed EVM address locally and deterministically, with no network calls or live chain data.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/address-checksum-evm
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-address-checksum-evm-a45fe148
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6zMDd2wBvd6XJxvexfWMC

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability delx-address-checksum-evm-a45fe148 -d '<json body>'
```

Example prompt: Can you produce the EIP-55 checksummed version of this EVM address: 0xd3cda913deb6f0967b57ab6e59b1c17802c2e76a?

## When to prefer this

Choose this endpoint when you need fast, cheap, stateless EIP-55 address formatting or validation with no RPC dependency — ideal for input sanitization pipelines, smart contract address normalization, and pre-transaction hygiene checks where live chain data is unnecessary. Prefer this over on-chain or RPC-based address tools when you want zero latency, no external API rate limits, and deterministic output for a fixed $0.003 per call.

## Known failure modes

- Invalid address format — non-hex characters or wrong length returns an error
- Address not 40 hex chars after stripping 0x prefix causes rejection
- Completely missing address field returns a schema validation error
- Malformed JSON input body causes a 400 bad request
- Payment not included or insufficient USDC via x402 returns a 402 response

## How this service works

Produce or validate an EIP-55 checksummed EVM address without network calls — call when producing or checking EIP-55 checksum addresses. Use for chain input hygiene without live RPC—adjacent to OneSource-class small chain reads, but static/local only so rights and margin stay clear. Returns deterministic machine-readable JSON for $0.003 USDC via x402 on Base. Execution is first-party, local-only, stateless, and memory-only with no paid upstream, no input retention, and no claim of live chain ti…

## Output

Returns a deterministic JSON object containing the EIP-55 checksummed form of the input EVM address and a validation status indicating whether the original input already matched the correct checksum.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "address": {
   "type": "string",
   "description": "EVM address (40 hex chars, optional 0x)."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "valid": true,
  "schema": "delx/util-address-checksum-evm/v1",
  "algorithm": "keccak256",
  "matches_input": true,
  "checksum_address": "0x95222290DD7278Aa3Ddd389Cc1E1d165CC4BAfe5"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-address-checksum-evm-a45fe148/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)