# OpenVerbs Chain Block Summary

> OpenVerbs Chain Block Summary is a paid API for AI agents from chain.openverbs.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Fetches a live block summary by number, hex, or tag from EVM chains, returning number, hash, parent, timestamp, transaction count, gas used/limit, base fee, and miner.

## Facts

- Endpoint: POST https://chain.openverbs.com/v1/block
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/openverbs-chain-block-summary-970b1af3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_t-Fh7v9_1-KWRqXOOggga

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 openverbs-chain-block-summary-970b1af3 -d '<json body>'
```

Example prompt: What are the details of the latest Ethereum block — give me the block number, hash, timestamp, transaction count, gas used, and base fee?

## When to prefer this

Use this endpoint when you need a comprehensive block-level snapshot from a live EVM chain — including gas, miner, timestamps, and transaction count — without constructing raw RPC calls. Prefer it over raw JSON-RPC when you want automatic endpoint fallback across Ethereum, Base, Arbitrum, Optimism, or Polygon, and need clean parsed output including both unix and ISO timestamps.

## Known failure modes

- Invalid block number or tag returns an error indicating the block was not found
- Unsupported chain name returns a validation error listing accepted chains
- Pending block tag may return null fields if the chain does not support it
- Network or RPC outages may cause delayed responses even with automatic fallback
- Hex block numbers must be properly formatted (0x prefix) or a parsing error is returned

## How this service works

Live block summary by number, hex, or tag (latest/earliest/pending/safe/finalized; default latest): number, hash, parent, timestamp (unix + ISO), transaction count, gas used/limit, base fee and miner. Reads live on-chain data with automatic endpoint fallback.

## Output

Returns a structured block summary including: block number (decimal and hex), block hash, parent hash, unix timestamp and ISO 8601 timestamp, transaction count, gas used, gas limit, base fee in wei, and miner address. Data is read live from the specified EVM chain with automatic endpoint fallback.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "chain": {
       "type": "string",
       "enum": [
        "ethereum",
        "base",
        "arbitrum",
        "optimism",
        "polygon"
       ],
       "description": "EVM chain to query. One of: ethereum, base, arbitrum, optimism, polygon. Default \"ethereum\"."
      },
      "block": {
       "type": [
        "string",
        "integer"
       ],
       "description": "Block number (decimal or 0x hex) or a tag: latest, earliest, pending, safe, finalized. Default latest."
      }
     },
     "required": [],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openverbs-chain-block-summary-970b1af3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chain.openverbs.com](https://www.zero.xyz/host/chain.openverbs.com/llms.txt)