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Neynar

Neynar Casts API

Operations related to casts.

Documentation Provider Profile APIs.io OpenAPI GitHub

Neynar Casts API is one of 39 APIs that Neynar publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Casts. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, a getting-started guide, and rate-limit docs.

This API exposes 4 operations across 4 paths, and defines 17 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.

4 operations 4 paths 17 schemas 4 GET

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
2.35.0
Base URL
https://api.neynar.com
Authentication
API Key
Contact
Neynar
Resource Areas
1

Authentication & Security 1

Neynar Casts 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 4

Across 4 paths, the API surfaces 4 operations — 4 GET. Each is listed below with its method, path, parameters, and response codes.

Casts 4

Operations related to casts.

GET
/v1/castById
By FID and Hash
lookup-cast-by-hash-and-fid 2 params → 200default
GET
/v1/castsByFid
By FID
fetch-users-casts 4 params → 200default
GET
/v1/castsByMention
Mentioning an FID
fetch-casts-mentioning-user 4 params → 200default
GET
/v1/castsByParent
By parent cast
fetch-casts-by-parent 6 params → 200default

Schemas 17

The contract defines 17 schemas that model the data the API accepts and returns. The most detailed are CastAddBody (7 properties), ErrorResponse (6 properties), MessageCommon (5 properties), MessageDataCommon (4 properties). Each schema is shown below with its type and property counts.

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 properties 6 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…
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 properties 3 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 properties 2 required
CastHash
string
A unique hash that identifies a specific cast within the creator's posts. Generated using HASHSCHEMEBLAKE3 of the cast's content.
MessageType
string
Type of the MessageBody. - MESSAGETYPECASTADD: Add a new Cast - MESSAGETYPECASTREMOVE: Remove an existing Cast - MESSAGETYPEREACTIONADD: Add a Reaction to a Ca…
SignatureScheme
string
Type of signature scheme used to sign the Message hash - SIGNATURESCHEMEED25519: Ed25519 signature (default) - SIGNATURESCHEMEEIP712: ECDSA signature using EIP…
MessageCommon
object
5 properties 5 required
CastAddBody
object
Adds a new Cast
7 properties 5 required
PaginationResponse
object
1 property 1 required
HashScheme
string
Type of hashing scheme used to produce a digest of MessageData. - HASHSCHEMEBLAKE3: Default scheme for hashing MessageData
UrlEmbed
object
1 property 1 required
CastEmbed
object
1 property 1 required
FarcasterNetwork
string
Farcaster network the message is intended for. - FARCASTERNETWORKMAINNET: Public primary network - FARCASTERNETWORKTESTNET: Public test network - FARCASTERNETW…
CastAdd
Embed

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

neynar-casts-api-openapi.yml Raw ↑

Other APIs Neynar publishes across the network.

Neynar Action API
AE Profile APIs.io
Neynar Agents API
AE Profile APIs.io
Neynar App Host API
AE Profile APIs.io
Neynar AuthAddress API
AE Profile APIs.io
Neynar Ban API
AE Profile APIs.io
Neynar Block API
AE Profile APIs.io
Neynar Cast API
AE Profile APIs.io
Neynar Channel API
AE Profile APIs.io
Neynar Feed API
AE Profile APIs.io
Neynar Fids API
AE Profile APIs.io
Neynar fname API
AE Profile APIs.io
Neynar Follows API
AE Profile APIs.io
#Casts
← Back to N APIs
API Details
ID
neynar:neynar-casts-api
Base URL
https://api.neynar.com
Docs
https://docs.neynar.com
Provider
Neynar
APIs.io →  GitHub →
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