Neynar Documentation

Authorizations

x-api-key

string

header

default:NEYNAR_API_DOCS

required

API key to authorize requests

Query Parameters

fid

integer

required

The FID of the reaction's creator

target_fid

integer

required

The FID of the cast's creator

target_hash

string

required

The cast's hash

reaction_type

enum<string>

default:Like

required

Type of interaction a user can have with content on the Farcaster network.

Like: Express appreciation for the target content. Similar to "likes" or "favorites" on other platforms.
Recast: Share the target content with the user's followers, similar to a "retweet" or "reblog". Helps increase content visibility.

Available options:

Like,

Recast

Example:

"Like"

Response

The requested Reaction.

hash

string

required

Example:

"0xd2b1ddc6c88e865a33cb1a565e0058d757042974"

hashScheme

enum<string>

default:HASH_SCHEME_BLAKE3

required

Type of hashing scheme used to produce a digest of MessageData. - HASH_SCHEME_BLAKE3: Default scheme for hashing MessageData

Available options:

HASH_SCHEME_BLAKE3

signature

string<byte>

required

signatureScheme

enum<string>

default:SIGNATURE_SCHEME_ED25519

required

Type of signature scheme used to sign the Message hash

SIGNATURE_SCHEME_ED25519: Ed25519 signature (default)
SIGNATURE_SCHEME_EIP712: ECDSA signature using EIP-712 scheme

Available options:

SIGNATURE_SCHEME_ED25519,

SIGNATURE_SCHEME_EIP712

signer

string

required

data

object

required

Represents a user's reaction to content on the Farcaster network. Reactions can be likes or recasts of casts, allowing users to express appreciation or share content with their followers.

Show child attributes

data.type

enum<string>

default:MESSAGE_TYPE_CAST_ADD

required

Type of the MessageBody.

MESSAGE_TYPE_CAST_ADD: Add a new Cast
MESSAGE_TYPE_CAST_REMOVE: Remove an existing Cast
MESSAGE_TYPE_REACTION_ADD: Add a Reaction to a Cast
MESSAGE_TYPE_REACTION_REMOVE: Remove a Reaction from a Cast
MESSAGE_TYPE_LINK_ADD: Add a new Link
MESSAGE_TYPE_LINK_REMOVE: Remove an existing Link
MESSAGE_TYPE_VERIFICATION_ADD_ETH_ADDRESS: Add a Verification of an Ethereum Address
MESSAGE_TYPE_VERIFICATION_REMOVE: Remove a Verification
MESSAGE_TYPE_USER_DATA_ADD: Add metadata about a user
MESSAGE_TYPE_USERNAME_PROOF: Add or replace a username proof
MESSAGE_TYPE_FRAME_ACTION: A Farcaster Frame action Type of the MessageBody.
MESSAGE_TYPE_CAST_ADD: Add a new Cast
MESSAGE_TYPE_CAST_REMOVE: Remove an existing Cast
MESSAGE_TYPE_REACTION_ADD: Add a Reaction to a Cast
MESSAGE_TYPE_REACTION_REMOVE: Remove a Reaction from a Cast
MESSAGE_TYPE_LINK_ADD: Add a new Link
MESSAGE_TYPE_LINK_REMOVE: Remove an existing Link
MESSAGE_TYPE_VERIFICATION_ADD_ETH_ADDRESS: Add a Verification of an Ethereum Address
MESSAGE_TYPE_VERIFICATION_REMOVE: Remove a Verification
MESSAGE_TYPE_USER_DATA_ADD: Add metadata about a user
MESSAGE_TYPE_USERNAME_PROOF: Add or replace a username proof
MESSAGE_TYPE_FRAME_ACTION: A Farcaster Frame action

Available options:

MESSAGE_TYPE_CAST_ADD,

MESSAGE_TYPE_CAST_REMOVE,

MESSAGE_TYPE_REACTION_ADD,

MESSAGE_TYPE_REACTION_REMOVE,

MESSAGE_TYPE_LINK_ADD,

MESSAGE_TYPE_LINK_REMOVE,

MESSAGE_TYPE_VERIFICATION_ADD_ETH_ADDRESS,

MESSAGE_TYPE_VERIFICATION_REMOVE,

MESSAGE_TYPE_USER_DATA_ADD,

MESSAGE_TYPE_USERNAME_PROOF,

MESSAGE_TYPE_FRAME_ACTION

data.fid

integer<uint64>

required

The unique identifier (FID) of the user who created this message. FIDs are assigned sequentially when users register on the network and cannot be changed.

Example:

2

data.timestamp

integer<int64>

required

Seconds since Farcaster Epoch (2021-01-01T00:00:00Z). Used to order messages chronologically and determine the most recent state. Must be within 10 minutes of the current time when the message is created.

Example:

48994466

data.network

enum<string>

default:FARCASTER_NETWORK_MAINNET

required

Farcaster network the message is intended for.

FARCASTER_NETWORK_MAINNET: Public primary network
FARCASTER_NETWORK_TESTNET: Public test network
FARCASTER_NETWORK_DEVNET: Private test network

Available options:

FARCASTER_NETWORK_MAINNET,

FARCASTER_NETWORK_TESTNET,

FARCASTER_NETWORK_DEVNET

data.reactionBody

object

required

Contains the type of reaction (like/recast) and the target content being reacted to. The target can be specified either by castId or URL.

Show child attributes

data.reactionBody.type

enum<string>

default:Like

required

Type of interaction a user can have with content on the Farcaster network.

Like: Express appreciation for the target content. Similar to "likes" or "favorites" on other platforms.
Recast: Share the target content with the user's followers, similar to a "retweet" or "reblog". Helps increase content visibility.

Available options:

Like,

Recast

Example:

"Like"

data.reactionBody.targetCastId

object

The unique identifier of the cast being reacted to. Must be a valid CastId containing the creator's FID and the cast's hash.

Show child attributes

data.reactionBody.targetCastId.fid

integer<uint64>

required

The Farcaster ID (FID) of the user who created the cast. Required to uniquely identify the cast's author in the network.

Example:

2

data.reactionBody.targetCastId.hash

string

required

A unique hash that identifies a specific cast within the creator's posts. Generated using HASH_SCHEME_BLAKE3 of the cast's content.

Example:

"0x03aff391a6eb1772b20b4ead9a89f732be75fe27"

data.reactionBody.targetUrl

string

The URL being reacted to. Used when reacting to external content or when the cast ID is not available.

Example:

"https://www.example.com/article"

Overview

Farcaster

Deploy onchain

Farcaster Hub API

Other SDKs

Github

By FID or cast

Authorizations

Query Parameters

Response