Loops

Loops Uploads API

Upload image assets for use in emails via a presigned-URL flow. 2 operation(s) in the Loops REST API v1 (OpenAPI 1.21.6).

Documentation GitHub OpenAPI

Operations 2

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

POST /v1/uploads Request a pre-signed URL to upload an image · Create an upload #

Ask an LLM

“How do I upload an image to use in my emails?”

“What image types and file sizes can I upload?”

Tell an agent

Get an upload URL for a {contentType} image of {contentLength} bytes.

Start an image upload of type {contentType}, size {contentLength} bytes.

POST /v1/uploads/{emailAssetId}/complete Finalize an image upload · Complete an upload #

Ask an LLM

“What do I do after putting the file to the pre-signed URL?”

“How do I get the public URL of an image I uploaded?”

Tell an agent

Complete upload {emailAssetId}.

Finalize image asset {emailAssetId} and give me its public URL.

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Loops OpenAPI Spec Uploads API
  description: This is the OpenAPI Spec for the Loops API.
  version: 1.21.6
servers:
- url: https://app.loops.so/api
tags:
- name: Uploads
  description: Upload image assets
paths:
  /v1/uploads:
    post:
      operationId: createUpload
      tags:
      - Uploads
      summary: Create an upload
      description: Request a pre-signed URL to upload an image asset. Upload the file with an HTTP `PUT` to the returned `presignedUrl` (sending the same `Content-Type` and `Content-Length`), then call `/uploads/{emailAssetId}/complete` to finalize the asset.
      x-mint:
        href: /api-reference/create-upload
        content: Request a pre-signed URL to upload an image asset. Upload the file with an HTTP `PUT` to the returned `presignedUrl` (sending the same `Content-Type` and `Content-Length`), then call [Complete an upload](/api-reference/complete-upload) to finalize the asset.
        metadata:
          description: Request a pre-signed URL to upload an image asset.
          sidebarTitle: Create an upload
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateUploadRequest'
      responses:
        '200':
          description: Pre-signed upload URL created.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CreateUploadResponse'
        '400':
          description: Invalid request body or unsupported `contentType`.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UploadFailureResponse'
        '401':
          description: Invalid API key or content API not enabled for this team.
        '405':
          description: Wrong HTTP request method.
        '413':
          description: Upload exceeds the maximum allowed size.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UploadFailureResponse'
      security:
      - apiKey: []
  /v1/uploads/{emailAssetId}/complete:
    parameters:
    - name: emailAssetId
      in: path
      required: true
      description: The `emailAssetId` returned when the upload was created via `POST /v1/uploads`.
      schema:
        type: string
        examples:
        - cla3s5s7e9t1i3d5f7g9h1j3
    post:
      operationId: completeUpload
      tags:
      - Uploads
      summary: Complete an upload
      description: Finalize an image upload after the file has been uploaded to the pre-signed URL. Returns the public URL of the uploaded image asset.
      x-mint:
        href: /api-reference/complete-upload
        metadata:
          description: Finalize an image upload after the file has been uploaded to the pre-signed URL.
      responses:
        '200':
          description: Upload completed.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/CompleteUploadResponse'
        '400':
          description: Upload id is missing or the uploaded file has an unsupported content type.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UploadFailureResponse'
        '401':
          description: Invalid API key or content API not enabled for this team.
        '404':
          description: Upload not found.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UploadFailureResponse'
        '405':
          description: Wrong HTTP request method.
        '429':
          description: Upload limit exceeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UploadLimitExceededFailureResponse'
      security:
      - apiKey: []
components:
  schemas:
    UploadFailureResponse:
      type: object
      properties:
        message:
          type: string
          examples:
          - Unsupported content type.
        supportedContentTypes:
          type: array
          description: Present when the request was rejected for an unsupported `contentType`. Lists the accepted MIME types.
          items:
            type: string
        maxBytes:
          type: integer
          description: Present when the upload exceeds the size limit. The maximum allowed size in bytes.
      required:
      - message
      examples:
      - message: Unsupported content type.
        supportedContentTypes:
        - image/jpeg
        - image/png
        - image/gif
        - image/webp
        maxBytes: 4000000
    CompleteUploadResponse:
      type: object
      properties:
        emailAssetId:
          type: string
          examples:
          - cla3s5s7e9t1i3d5f7g9h1j3
          description: The ID of the created asset.
        finalUrl:
          type: string
          description: The public URL of the uploaded asset.
          examples:
          - https://assets.loops.so/cla3s5s7e9t1i3d5f7g9h1j3/logo.png
      required:
      - emailAssetId
      - finalUrl
      examples:
      - emailAssetId: cla3s5s7e9t1i3d5f7g9h1j3
        finalUrl: https://assets.loops.so/cla3s5s7e9t1i3d5f7g9h1j3/logo.png
    CreateUploadResponse:
      type: object
      properties:
        emailAssetId:
          type: string
          examples:
          - cla3s5s7e9t1i3d5f7g9h1j3
          description: The ID of the created asset. Pass this as `emailAssetId` to `POST /v1/uploads/{emailAssetId}/complete` once the file has been uploaded.
        presignedUrl:
          type: string
          description: The pre-signed URL to upload the file to with an HTTP `PUT` request. Send the same `Content-Type` and `Content-Length` used in the create request.
          examples:
          - https://loops-assets.s3.amazonaws.com/uploads/cla3s5s7e9t1i3d5f7g9h1j3?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=...
      required:
      - emailAssetId
      - presignedUrl
      examples:
      - emailAssetId: cla3s5s7e9t1i3d5f7g9h1j3
        presignedUrl: https://loops-assets.s3.amazonaws.com/uploads/cla3s5s7e9t1i3d5f7g9h1j3?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=...
    CreateUploadRequest:
      type: object
      properties:
        contentType:
          type: string
          description: The MIME type of the file to upload. Supported types are `image/jpeg`, `image/png`, `image/gif` and `image/webp`.
          examples:
          - image/png
        contentLength:
          type: integer
          description: The size of the file in bytes. Must be a positive integer no greater than 4,000,000 bytes.
          examples:
          - 102400
      required:
      - contentType
      - contentLength
      additionalProperties: false
    UploadLimitExceededFailureResponse:
      type: object
      properties:
        message:
          type: string
          examples:
          - 'Upload limit exceeded: max 50 uploads per 24 hours. Please contact support if you need to increase your upload limit.'
        maxUploads:
          type: integer
          description: The maximum number of uploads allowed per window.
          examples:
          - 50
        windowHours:
          type: integer
          description: The number of hours in the upload limit window.
          examples:
          - 24
  securitySchemes:
    apiKey:
      type: http
      scheme: bearer