Neynar · Schema

Hub Message

A Message is a delta operation on the Farcaster network that represents a state change. Messages are the fundamental unit of data in Farcaster and can represent various actions like: - Creating or removing casts (posts) - Adding or removing reactions - Following or unfollowing users - Updating profile data - Verifying Ethereum addresses Each message contains: - A MessageData object with the actual content - A hash of the content for integrity verification - A cryptographic signature to prove authenticity - The signer's public key for verification Messages are immutable once created and form an append-only log of all user actions on the network.

FarcasterSocialDecentralizedWeb3BlockchainSocial GraphCastsChannelsFeedsReactionsNotificationWebhookOnchain
View JSON Schema on GitHub

JSON Schema

hub-message.json Raw ↑
{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://neynar.com/schemas/hub/Message",
  "title": "Hub Message",
  "description": "A Message is a delta operation on the Farcaster network that represents a state change. Messages are the fundamental unit of data in Farcaster and can represent various actions like:\n- Creating or removing casts (posts)\n- Adding or removing reactions\n- Following or unfollowing users\n- Updating profile data\n- Verifying Ethereum addresses\n\nEach message contains:\n- A MessageData object with the actual content\n- A hash of the content for integrity verification\n- A cryptographic signature to prove authenticity\n- The signer's public key for verification\n\nMessages are immutable once created and form an append-only log of all user actions on the network.",
  "allOf": [
    {
      "type": "object",
      "properties": {
        "data": {
          "oneOf": [
            {
              "$ref": "#/components/schemas/MessageDataCastAdd"
            },
            {
              "$ref": "#/components/schemas/MessageDataCastRemove"
            },
            {
              "$ref": "#/components/schemas/MessageDataReaction"
            },
            {
              "$ref": "#/components/schemas/MessageDataLink"
            },
            {
              "$ref": "#/components/schemas/MessageDataVerificationAdd"
            },
            {
              "$ref": "#/components/schemas/MessageDataVerificationRemove"
            },
            {
              "$ref": "#/components/schemas/MessageDataUserDataAdd"
            },
            {
              "$ref": "#/components/schemas/MessageDataUsernameProof"
            },
            {
              "$ref": "#/components/schemas/MessageDataFrameAction"
            }
          ],
          "discriminator": {
            "propertyName": "type",
            "mapping": {
              "MESSAGE_TYPE_CAST_ADD": "#/components/schemas/MessageDataCastAdd",
              "MESSAGE_TYPE_CAST_REMOVE": "#/components/schemas/MessageDataCastRemove",
              "MESSAGE_TYPE_REACTION_ADD": "#/components/schemas/MessageDataReaction",
              "MESSAGE_TYPE_REACTION_REMOVE": "#/components/schemas/MessageDataReaction",
              "MESSAGE_TYPE_LINK_ADD": "#/components/schemas/MessageDataLink",
              "MESSAGE_TYPE_LINK_REMOVE": "#/components/schemas/MessageDataLink",
              "MESSAGE_TYPE_VERIFICATION_ADD_ETH_ADDRESS": "#/components/schemas/MessageDataVerificationAdd",
              "MESSAGE_TYPE_VERIFICATION_REMOVE": "#/components/schemas/MessageDataVerificationRemove",
              "MESSAGE_TYPE_USER_DATA_ADD": "#/components/schemas/MessageDataUserDataAdd",
              "MESSAGE_TYPE_USERNAME_PROOF": "#/components/schemas/MessageDataUsernameProof",
              "MESSAGE_TYPE_FRAME_ACTION": "#/components/schemas/MessageDataFrameAction"
            }
          }
        }
      },
      "required": [
        "data"
      ]
    },
    {
      "$ref": "#/components/schemas/MessageCommon"
    }
  ]
}

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