Neynar Documentation

The Reactions API

The Reactions API will accept the following values for the reaction_type field.

String	Description
Like	Like the target cast
Recast	Share target cast to the user’s audience

reactionById

Get a reaction by its created FID and target Cast.
Query Parameters

Parameter	Description	Example
fid	The FID of the reaction’s creator	`fid=6833`
target_fid	The FID of the cast’s creator	`target_fid=2`
target_hash	The cast’s hash	`target_hash=0xa48dd46161d8e57725f5e26e34ec19c13ff7f3b9`
reaction_type	The type of reaction, use string representation	`reaction_type=Like` OR `reaction_type=Recast`

Example

curl http://127.0.0.1:3381/v1/reactionById?fid=2&reaction_type=Like&target_fid=1795&target_hash=0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0

Response

{
  "data": {
    "type": "MESSAGE_TYPE_REACTION_ADD",
    "fid": 2,
    "timestamp": 72752656,
    "network": "FARCASTER_NETWORK_MAINNET",
    "reactionBody": {
      "type": "REACTION_TYPE_LIKE",
      "targetCastId": {
        "fid": 1795,
        "hash": "0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0"
      }
    }
  },
  "hash": "0x9fc9c51f6ea3acb84184efa88ba4f02e7d161766",
  "hashScheme": "HASH_SCHEME_BLAKE3",
  "signature": "F2OzKsn6Wj...gtyORbyCQ==",
  "signatureScheme": "SIGNATURE_SCHEME_ED25519",
  "signer": "0x78ff9a7...647b6d62558c"
}

reactionsByFid

Get all reactions by an FID
Query Parameters

Parameter	Description	Example
fid	The FID of the reaction’s creator	`fid=6833`
reaction_type	The type of reaction, use string representation	`reaction_type=Like` OR `reaction_type=Recast`
pageSize	Optional page size (default: 1000)	`pageSize=100`
pageToken	Optional page token for pagination	`pageToken=DAEDAAAGlQ...`
reverse	Optional reverse order flag	`reverse=true`

Example

curl http://127.0.0.1:3381/v1/reactionsByFid?fid=2&reaction_type=Like

Response

{
  "messages": [
    {
      "data": {
        "type": "MESSAGE_TYPE_REACTION_ADD",
        "fid": 2,
        "timestamp": 72752656,
        "network": "FARCASTER_NETWORK_MAINNET",
        "reactionBody": {
          "type": "REACTION_TYPE_LIKE",
          "targetCastId": {
            "fid": 1795,
            "hash": "0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0"
          }
        }
      },
      "hash": "0x9fc9c51f6ea3acb84184efa88ba4f02e7d161766",
      "hashScheme": "HASH_SCHEME_BLAKE3",
      "signature": "F2OzKsn6WjP8MTw...hqUbrAvp6mggtyORbyCQ==",
      "signatureScheme": "SIGNATURE_SCHEME_ED25519",
      "signer": "0x78ff9a768...62558c"
    }
  ],
  "nextPageToken": ""
}

reactionsByCast

Get all reactions to a cast
Query Parameters

Parameter	Description	Example
target_fid	The FID of the cast’s creator	`target_fid=6833`
target_hash	The hash of the cast	`target_hash=0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0`
reaction_type	The type of reaction, use string representation	`reaction_type=Like` OR `reaction_type=Recast`
pageSize	Optional page size (default: 1000)	`pageSize=100`
pageToken	Optional page token for pagination	`pageToken=DAEDAAAGlQ...`
reverse	Optional reverse order flag	`reverse=true`

Example

curl http://127.0.0.1:3381/v1/reactionsByCast?target_fid=2&reaction_type=Like&target_hash=0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0

Response

{
  "messages": [
    {
      "data": {
        "type": "MESSAGE_TYPE_REACTION_ADD",
        "fid": 426,
        "timestamp": 72750141,
        "network": "FARCASTER_NETWORK_MAINNET",
        "reactionBody": {
          "type": "REACTION_TYPE_LIKE",
          "targetCastId": {
            "fid": 1795,
            "hash": "0x7363f449bfb0e7f01c5a1cc0054768ed5146abc0"
          }
        }
      },
      "hash": "0x7662fba1be3166fc75acc0914a7b0e53468d5e7a",
      "hashScheme": "HASH_SCHEME_BLAKE3",
      "signature": "tmAUEYlt/+...R7IO3CA==",
      "signatureScheme": "SIGNATURE_SCHEME_ED25519",
      "signer": "0x13dd2...204e57bc2a"
    }
  ],
  "nextPageToken": ""
}

reactionsByTarget

Get all reactions to cast’s target URL
Query Parameters

Parameter	Description	Example
url	The URL of the parent cast	`url=chain://eip155:1/erc721:0x39d89b649ffa044383333d297e325d42d31329b2`
reaction_type	The type of reaction, use string representation	`reaction_type=Like` OR `reaction_type=Recast`

Example

curl http://127.0.0.1:3381/v1/reactionsByTarget?url=chain://eip155:1/erc721:0x39d89b649ffa044383333d297e325d42d31329b2

Response

{
  "messages": [
    {
      "data": {
        "type": "MESSAGE_TYPE_REACTION_ADD",
        "fid": 1134,
        "timestamp": 79752856,
        "network": "FARCASTER_NETWORK_MAINNET",
        "reactionBody": {
          "type": "REACTION_TYPE_LIKE",
          "targetUrl": "chain://eip155:1/erc721:0x39d89b649ffa044383333d297e325d42d31329b2"
        }
      },
      "hash": "0x94a0309cf11a07b95ace71c62837a8e61f17adfd",
      "hashScheme": "HASH_SCHEME_BLAKE3",
      "signature": "+f/+M...0Uqzd0Ag==",
      "signatureScheme": "SIGNATURE_SCHEME_ED25519",
      "signer": "0xf6...3769198d4c"
    }
  ],
  "nextPageToken": ""
}