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Neynar

Neynar Reactions API

Operations related to reactions.

Documentation Provider Profile APIs.io OpenAPI GitHub

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

Tagged areas include Reactions. 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 15 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 15 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 Reactions 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.

Reactions 4

Operations related to reactions.

GET
/v1/reactionById
By FID or cast
lookup-reaction-by-id 4 params → 200default
GET
/v1/reactionsByCast
On cast
fetch-cast-reactions 6 params → 200default
GET
/v1/reactionsByFid
By FID
fetch-user-reactions 5 params → 200default
GET
/v1/reactionsByTarget
To a target URL
fetch-reactions-by-target 5 params → 200default

Schemas 15

The contract defines 15 schemas that model the data the API accepts and returns. The most detailed are ErrorResponse (6 properties), MessageCommon (5 properties), MessageDataCommon (4 properties), ReactionBody (3 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
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 properties 1 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 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.
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…
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
PaginationResponse
object
1 property 1 required
Reaction
HashScheme
string
Type of hashing scheme used to produce a digest of MessageData. - HASHSCHEMEBLAKE3: Default scheme for hashing MessageData
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…
FarcasterNetwork
string
Farcaster network the message is intended for. - FARCASTERNETWORKMAINNET: Public primary network - FARCASTERNETWORKTESTNET: Public test network - FARCASTERNETW…

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

neynar-reactions-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 Casts 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
#Reactions
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API Details
ID
neynar:neynar-reactions-api
Base URL
https://api.neynar.com
Docs
https://docs.neynar.com
Provider
Neynar
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