# EVM Contract Storage Slot Reader

> EVM Contract Storage Slot Reader is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-13).

Reads a raw storage slot of a smart contract (by decimal, hex, or EIP-1967 standard slots) on 12 EVM chains, returning the value as hex, integer, and address.

## Facts

- Endpoint: POST https://api.vextorium.com/evm-storage-pago?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-contract-storage-slot-reader-58236926
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tNKorCYj65QCbMPam7rLu

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 evm-contract-storage-slot-reader-58236926 -d '<json body>'
```

Example prompt: What's stored in storage slot 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc (the EIP-1967 implementation slot) of contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base?

## When to prefer this

Use this endpoint when you need to inspect raw EVM contract storage — especially for proxy contract patterns (EIP-1967, transparent proxy, beacon proxy) to find implementation or admin addresses, or when you need to read arbitrary storage slots across 12 major EVM chains including Base, Ethereum, Arbitrum, Optimism, Polygon, BNB Chain, Avalanche, Gnosis, Linea, Scroll, Sonic, and Unichain. Prefer this over generic RPC calls when you need the value returned as hex, integer, and address simultaneously with no RPC setup required.

## Known failure modes

- Invalid contract address format returns an error
- Unsupported chain identifier returns validation error
- Non-existent block number may return error or revert
- Malformed slot identifier (not valid hex or decimal) causes rejection
- Network RPC unavailability for a specific chain may cause timeout
- Empty slot returns vacio:true with zero-value hex

## How this service works

Read a raw storage slot of a contract (decimal, hex or the standard EIP-1967 implementation/admin/beacon slots), as integer and as address, at any block. Works on Base, Ethereum, Arbitrum, Optimism, Polygon, BNB Chain, Avalanche, Gnosis, Linea, Scroll, Sonic and Unichain.

## Output

Returns a JSON object with the chain name, contract address, slot identifier, a boolean indicating if the slot is empty, the raw 32-byte hex value, the value as a decimal integer string, and the value interpreted as an Ethereum address (last 20 bytes).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "red": {
   "enum": [
    "base",
    "ethereum",
    "arbitrum",
    "optimism",
    "polygon",
    "bnb",
    "avalanche",
    "gnosis",
    "linea",
    "scroll",
    "sonic",
    "unichain"
   ],
   "type": "string",
   "description": "Chain (default base)"
  },
  "slot": {
   "type": "string"
  },
  "bloque": {
   "type": "string"
  },
  "contrato": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "red": "base",
  "slot": "0x0",
  "vacio": false,
  "contrato": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "valor_hex": "0x0000000000000000000000003abd6f64a422225e61e435bae41db12096106df7",
  "valor_entero": "335346009260450724142082839821853564916387048951",
  "como_direccion": "0x3ABd6f64A422225E61E435baE41db12096106df7"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-contract-storage-slot-reader-58236926/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)