Neynar Message API is one of 39 APIs that Neynar publishes on the APIs.io network, described by a machine-readable OpenAPI specification.
Tagged areas include Message. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, a getting-started guide, and rate-limit docs.
This API exposes
2 operations
across 2 paths,
and defines 36 schemas.
It is described by OpenAPI 3.2.0, at version 2.35.0.
Requests are made against a single base URL, https://snapchain-api.neynar.com.
2 operations2 paths36 schemas2 POST
Metadata
The identity and technical contract details declared by the specification.
Neynar Message API declares
1 security scheme
for authenticating requests.
An API key is passed in the header as x-api-key (ApiKeyAuth).
By default, every request must be authenticated.
ApiKeyAuth — API key to authorize requests
Paths & Operations 2
Across 2 paths, the API surfaces 2 operations — 2 POST. Each is listed below with its method, path, parameters, and response codes.
Message 2
Operations related to messages.
POST
/v1/submitMessage
Submit signed message
publish-messagebody→ 200default
POST
/v1/validateMessage
Validate signed message
validate-messagebody→ 200default
Schemas 36
The contract defines 36 schemas that model the data the API accepts and returns. The most detailed are CastAddBody (7 properties), ErrorResponse (6 properties), UserNameProof (6 properties), MessageCommon (5 properties). Each schema is shown below with its type and property counts.
UserDataType
string
Specifies which field of a user's profile is being updated. - USERDATATYPEPFP: Profile Picture URL for the user's avatar - USERDATATYPEDISPLAY: Display Name sh…
FidSchema
integer
Farcaster ID (FID). A unique identifier assigned to each user in the Farcaster network. This number is permanent and cannot be changed. FIDs are assigned seque…
ErrorResponse
object
6 properties6 required
MessageDataCastAdd
Represents a new cast (post) being created in the Farcaster network. A cast can include text content, mentions of other users, embedded URLs, and references to…
ReactionBody
object
Specifies the details of a reaction to content on Farcaster. A reaction must specify its type (like/recast) and either a target cast ID or URL to react to. Onl…
3 properties1 required
MessageDataFrameAction
Represents a user's interaction with a Farcaster Frame, which is an interactive element embedded within a cast. Frames allow users to engage with content throu…
VerificationRemoveBody
object
Contains the data required to remove a previously added blockchain address verification from a user's profile. This operation permanently removes the verificat…
1 property1 required
MessageDataCommon
object
Common properties shared by all Farcaster message types. These properties provide essential metadata about the message's origin, timing, and network context.
4 properties3 required
CastId
object
A unique identifier for a cast (post) in the Farcaster network, consisting of the creator's FID and a hash of the cast's content. This combination ensures glob…
2 properties2 required
CastHash
string
A unique hash that identifies a specific cast within the creator's posts. Generated using HASHSCHEMEBLAKE3 of the cast's content.
FrameActionBody
object
Contains the data for a user's interaction with a Farcaster Frame. Frames are interactive elements within casts that can have up to 4 clickable buttons, allowi…
3 properties3 required
MessageType
string
Type of the MessageBody. - MESSAGETYPECASTADD: Add a new Cast - MESSAGETYPECASTREMOVE: Remove an existing Cast - MESSAGETYPEREACTIONADD: Add a Reaction to a Ca…
MessageDataReaction
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 c…
UserNameProof
object
6 properties6 required
LinkType
string
Defines the type of social connection between users. - follow: Establishes a following relationship where the user will receive updates from the target user in…
SignatureScheme
string
Type of signature scheme used to sign the Message hash - SIGNATURESCHEMEED25519: Ed25519 signature (default) - SIGNATURESCHEMEEIP712: ECDSA signature using EIP…
MessageCommon
object
5 properties5 required
CastAddBody
object
Adds a new Cast
7 properties5 required
VerificationAddEthAddressBody
object
Contains the data required to verify ownership of an Ethereum or Solana address. The verification process requires a cryptographic signature from the blockchai…
3 properties3 required
MessageDataUserDataAdd
Represents a message that updates a user's profile metadata. This can include changes to profile picture, display name, bio, URL, or preferred username. Each u…
ValidateMessageResponse
object
2 properties2 required
UserDataBody
object
Contains the data for updating a specific field of a user's profile metadata. Each update operation modifies one profile field at a time, allowing granular con…
2 properties2 required
MessageDataVerificationRemove
Represents a message that removes an existing blockchain address verification from a user's profile. This allows users to disassociate previously verified addr…
MessageDataVerificationAdd
Represents a message that adds verification of ownership for an Ethereum or Solana address to a user's profile. This verification proves that the user controls…
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 represen…
MessageDataLink
Represents a social graph connection between users in the Farcaster network. Currently supports following relationships between users.
HashScheme
string
Type of hashing scheme used to produce a digest of MessageData. - HASHSCHEMEBLAKE3: Default scheme for hashing MessageData
MessageDataCastRemove
Represents a request to remove (delete) a previously created cast. Only the original creator of a cast can remove it.
UserNameType
string
ReactionType
string
Type of interaction a user can have with content on the Farcaster network. - Like: Express appreciation for the target content. Similar to "likes" or "favorite…
UrlEmbed
object
1 property1 required
CastEmbed
object
1 property1 required
LinkBody
object
Defines a social connection between users in the Farcaster network. Currently used to establish following relationships, allowing users to curate their content…
3 properties2 required
FarcasterNetwork
string
Farcaster network the message is intended for. - FARCASTERNETWORKMAINNET: Public primary network - FARCASTERNETWORKTESTNET: Public test network - FARCASTERNETW…
MessageDataUsernameProof
Embed
Specification
The full machine-readable OpenAPI contract behind this narrative.
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