> ## Documentation Index
> Fetch the complete documentation index at: https://docs.phoenix.trade/llms.txt
> Use this file to discover all available pages before exploring further.

# Submit register trader transaction

> Validates a base64-encoded transaction for the default trader account, signs it with the Phoenix onboarder, simulates it to ensure the onboarder pays no lamports, sends it to Phoenix's RPC, and returns the transaction signature.



## OpenAPI

````yaml /openapi/phoenix-public-api.json post /v1/exchange/send-register-ixs
openapi: 3.1.0
info:
  title: Phoenix Eternal API
  description: >-
    RESTful API for accessing Phoenix Eternal perpetual trading data. Provides
    real-time orderbook levels, asset information, and market metadata.
  termsOfService: https://www.phoenix.trade/terms-of-service
  contact:
    name: Phoenix Development Team
    url: https://github.com/Ellipsis-Labs/phoenix
  license:
    name: Proprietary
  version: 1.0.0
servers:
  - url: https://perp-api.phoenix.trade
    description: Phoenix Eternal Perp API
security: []
tags:
  - name: Auth
    description: Wallet and session authentication.
  - name: Exchange
    description: Exchange, market, candle, and no-referral register-instruction workflows.
  - name: Invite
    description: Invite validation, referral activation, and wallet allowlist checks.
  - name: Notifications
    description: Trader notification reads and acknowledgement helpers.
  - name: Trader
    description: Trader state, account history, and transaction builders.
externalDocs:
  url: https://docs.phoenix.trade
  description: Phoenix developer documentation
paths:
  /v1/exchange/send-register-ixs:
    post:
      tags:
        - Exchange
      summary: Submit register trader transaction
      description: >-
        Validates a base64-encoded transaction for the default trader account,
        signs it with the Phoenix onboarder, simulates it to ensure the
        onboarder pays no lamports, sends it to Phoenix's RPC, and returns the
        transaction signature.
      operationId: post.v1.exchange.send_register_ixs
      requestBody:
        description: JSON request payload for `post.v1.exchange.send_register_ixs`.
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendRegisterIxsRequest'
            example:
              traderAuthority: string
              transaction: string
              txFeePayer: string
        required: true
      responses:
        '200':
          description: ''
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SendRegisterIxsResponse'
components:
  schemas:
    SendRegisterIxsRequest:
      type: object
      description: Request payload for /exchange/send-register-ixs.
      required:
        - transaction
        - traderAuthority
        - txFeePayer
      properties:
        maxPositions:
          type:
            - integer
            - 'null'
          format: int32
          minimum: 0
        traderAuthority:
          type: string
        traderPdaIndex:
          type:
            - integer
            - 'null'
          format: int32
          minimum: 0
        traderSubaccountIndex:
          type:
            - integer
            - 'null'
          format: int32
          minimum: 0
        transaction:
          type: string
          description: >-
            Base64-encoded Solana transaction wire bytes signed by the
            user-owned

            required signers. The API validates, signs as onboarder, simulates,
            and

            submits it.
        txFeePayer:
          type: string
    SendRegisterIxsResponse:
      type: object
      description: Response payload for /exchange/send-register-ixs.
      required:
        - signature
        - traderPda
        - traderOnboarder
        - txFeePayer
        - maxPositions
        - includeRegisterTrader
      properties:
        includeRegisterTrader:
          type: boolean
        maxPositions:
          type: integer
          format: int32
          minimum: 0
        signature:
          type: string
        traderOnboarder:
          type: string
        traderPda:
          type: string
        txFeePayer:
          type: string

````