# Gets a proof for a given light block header inside a state proof commitment

GET

/v2/blocks/{round}/lightheader/proof

## Authorizations

- **[api_key](https://dev.algorand.co/reference/rest-api/algod/#api_key)**

## Parameters

### Path Parameters

**round**  
required  
integer  
A round number.

## Responses

### 200

Proof of a light block header.

Select media typeapplication/json

Proof of membership and position of a light block header.

object

**index**  
required  
The index of the light block header in the vector commitment tree

integer

**proof**  
required  
The encoded proof.

string format: byte

/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/

**treedepth**  
required  
Represents the depth of the tree that is being proven, i.e. the number of edges from a leaf to the root.

integer

### 401

Invalid API Token

Select media typeapplication/json

An error response with optional data field.

object

**data**  
object  
  
**message**  
required  
string

### 404

Could not create proof since some data is missing

Select media typeapplication/json

An error response with optional data field.

object

**data**  
object  
  
**message**  
required  
string

### 408

Timed out on request

Select media typeapplication/json

An error response with optional data field.

object

**data**  
object  
  
**message**  
required  
string

### 500

Internal Error

Select media typeapplication/json

An error response with optional data field.

object

**data**  
object  
  
**message**  
required  
string

### 503

Service Temporarily Unavailable

Select media typeapplication/json

An error response with optional data field.

object

**data**  
object  
  
**message**  
required  
string

### default

Unknown Error