## By parent cast

### cURL

```
curl --request GET \
  --url https://snapchain-api.neynar.com/v1/castsByParent \
  --header 'x-api-key: NEYNAR_API_DOCS'
```

### Python

```
import requests

url = "https://snapchain-api.neynar.com/v1/castsByParent"

headers = {"x-api-key": "NEYNAR_API_DOCS"}

response = requests.get(url, headers=headers)

print(response.text)
```

### JavaScript

```
const options = {method: 'GET', headers: {'x-api-key': 'NEYNAR_API_DOCS'}};

fetch('https://snapchain-api.neynar.com/v1/castsByParent', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));
```

### PHP

```
<?php

$curl = curl_init();

curl_setopt_array($curl, [\
  CURLOPT_URL => "https://snapchain-api.neynar.com/v1/castsByParent",\
  CURLOPT_RETURNTRANSFER => true,\
  CURLOPT_ENCODING => "",\
  CURLOPT_MAXREDIRS => 10,\
  CURLOPT_TIMEOUT => 30,\
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,\
  CURLOPT_CUSTOMREQUEST => "GET",\
  CURLOPT_HTTPHEADER => [\
    "x-api-key: NEYNAR_API_DOCS"\
  ],\
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}
```

### Go

```
package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

url := "https://snapchain-api.neynar.com/v1/castsByParent"

req, _ := http.NewRequest("GET", url, nil)

req.Header.Add("x-api-key", "NEYNAR_API_DOCS")

res, _ := http.DefaultClient.Do(req)

defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

fmt.Println(string(body))
}
```

### Unirest

```
HttpResponse<String> response = Unirest.get("https://snapchain-api.neynar.com/v1/castsByParent")
  .header("x-api-key", "NEYNAR_API_DOCS")
  .asString();
```

### Ruby

```
require 'uri'
require 'net/http'

url = URI("https://snapchain-api.neynar.com/v1/castsByParent")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["x-api-key"] = 'NEYNAR_API_DOCS'

response = http.request(request)
puts response.read_body
```

## Response Structure

### Example Response

```json
{
  "messages": [
    {
      "hash": "0xd2b1ddc6c88e865a33cb1a565e0058d757042974",
      "hashScheme": "HASH_SCHEME_BLAKE3",
      "signature": "aSDinaTvuI8gbWludGxpZnk=",
      "signatureScheme": "SIGNATURE_SCHEME_ED25519",
      "signer": "<string>",
      "data": {
        "type": "MESSAGE_TYPE_CAST_ADD",
        "fid": 2,
        "timestamp": 48994466,
        "network": "FARCASTER_NETWORK_MAINNET",
        "castAddBody": {
          "embedsDeprecated": ["<string>"],
          "mentions": [2],
          "text": "<string>",
          "mentionsPositions": [123],
          "embeds": [{
            "castId": {
              "fid": 2,
              "hash": "0x03aff391a6eb1772b20b4ead9a89f732be75fe27"
            }
          }],
          "parentCastId": {
            "fid": 2,
            "hash": "0x03aff391a6eb1772b20b4ead9a89f732be75fe27"
          },
          "parentUrl": "chain://eip155:1/erc721:0x39d89b649ffa044383333d297e325d42d31329b2"
        }
      }
    }
  ],
  "nextPageToken": "AuzO1V0DtaItCwwa10X6YsfStlynsGWT"
}
```

### Error Response Structure

```json
{
  "errCode": "<string>",
  "presentable": true,
  "name": "<string>",
  "code": 123,
  "details": "<string>",
  "metadata": {
    "errcode": ["<string>"]
  }
}
```

## Authorization

**Header Parameter**: x-api-key - required
 - **default**: `NEYNAR_API_DOCS`

## Query Parameters

- **fid**: Integer<uint64> - The Farcaster ID (FID) of the parent cast's creator.
  - Required: Yes when using hash-based lookup.
- **hash**: String - The unique hash identifier of the parent cast.
  - Required: Yes when using hash-based lookup.
- **url**: String<uri> - Cast URL starting with 'chain://'.
- **pageSize**: Integer - Maximum number of messages to return in a single response.
- **reverse**: Boolean - Reverse the sort order.
- **pageToken**: String - The page token from the previous query.