Farcaster

Farcaster Submit API

The Submit API from Farcaster — 3 operation(s) for submit.

GitHub OpenAPI

Operations 3

POST /v1/submitMessage Submit a signed protobuf message to the hub #
POST /v1/submitBulkMessages Submit a batch of signed protobuf messages #
POST /v1/validateMessage Validate a signed protobuf message without writing #

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/farcaster/refs/heads/main/openapi/farcaster-submit-api-openapi.yml

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OpenAPI Specification

farcaster-submit-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Farcaster Snapchain Hub HTTP Submit API
  description: HTTP query interface for Farcaster's Snapchain network. Read casts, reactions, follows, user data, verifications and on-chain events by FID; submit signed protobuf messages; and stream hub events. The public reference endpoint is hosted at https://snapchain.farcaster.xyz, but operators typically run their own Snapchain node and bind the HTTP server to a local port (default 3381).
  version: 1.0.0
  contact:
    name: Farcaster
    url: https://snapchain.farcaster.xyz/
  license:
    name: MIT
servers:
- url: https://snapchain.farcaster.xyz
  description: Public Snapchain reference endpoint
- url: http://127.0.0.1:3381
  description: Default local Snapchain HTTP server
tags:
- name: Submit
paths:
  /v1/submitMessage:
    post:
      tags:
      - Submit
      summary: Submit a signed protobuf message to the hub
      requestBody:
        required: true
        content:
          application/octet-stream:
            schema:
              type: string
              format: binary
      responses:
        '200':
          description: Submitted message
      operationId: postV1SubmitMessage
      x-operation-id-source: derived
  /v1/submitBulkMessages:
    post:
      tags:
      - Submit
      summary: Submit a batch of signed protobuf messages
      requestBody:
        required: true
        content:
          application/octet-stream:
            schema:
              type: string
              format: binary
      responses:
        '200':
          description: Submission result
      operationId: postV1SubmitBulkMessages
      x-operation-id-source: derived
  /v1/validateMessage:
    post:
      tags:
      - Submit
      summary: Validate a signed protobuf message without writing
      requestBody:
        required: true
        content:
          application/octet-stream:
            schema:
              type: string
              format: binary
      responses:
        '200':
          description: Validation result
      operationId: postV1ValidateMessage
      x-operation-id-source: derived