> ## Documentation Index
> Fetch the complete documentation index at: https://docs.chainstack.com/llms.txt
> Use this file to discover all available pages before exploring further.

# debug_traceBlockByNumber | Optimism

> Reference docs for the debug_traceBlockByNumber JSON-RPC method on the Optimism blockchain, available via Chainstack JSON-RPC nodes.

The `debug_traceBlockByNumber` RPC method is used to retrieve detailed execution traces for all transactions included in a block, identified by the block's number. This method is particularly useful for developers and analysts who need to deeply understand transaction execution and state changes within a specific block.

## Request

To use `debug_traceBlockByNumber`, send a POST request with a JSON RPC call in the body.

## Parameters

* **Block Number** (`string`): The number of the block for which to retrieve the execution traces, in hexadecimal format.

## Response

The response includes detailed execution traces for all transactions in the specified block.

* **result** (`array`): An array of execution traces for each transaction in the block. Each trace provides comprehensive details about the execution, including calls, state changes, and gas usage.

## Use case

The `debug_traceBlockByNumber` method is essential for:

* Developers debugging complex interactions within a block.
* Analysts conducting forensic analysis of block transactions.
* Tools and services that provide insights into the Ethereum Virtual Machine (EVM) execution and state changes.


## OpenAPI

````yaml openapi/optimism_node_api/debug_traceBlockByNumber.json POST /efb0a5eccd2caa5135eb54eba6f7f300
openapi: 3.0.0
info:
  title: debug_traceBlockByNumber example
  version: 1.0.0
  description: >-
    This API example demonstrates how to use the debug_traceBlockByNumber method
    to retrieve detailed execution  traces for all transactions included in a
    block, identified by the block's number.
servers:
  - url: https://optimism-mainnet.core.chainstack.com
security: []
paths:
  /efb0a5eccd2caa5135eb54eba6f7f300:
    post:
      tags:
        - Debug Operations
      summary: debug_traceBlockByNumber
      operationId: traceBlockByNumber
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - jsonrpc
                - method
                - id
                - params
              properties:
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: debug_traceBlockByNumber
                id:
                  type: integer
                  default: 1
                params:
                  type: array
                  items:
                    type: string
                  default:
                    - '0x6eee7bc'
      responses:
        '200':
          description: >-
            Detailed execution traces for all transactions in the specified
            block
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: array
                    items:
                      type: object
                    description: >-
                      An array of execution traces for each transaction in the
                      block.

````