sleek-design-mobile-apps

Designing with Sleek

Overview

Sleek is an AI-powered mobile app design tool. You interact with it via a REST API at /api/v1/* to create projects, describe what you want built in plain language, and get back rendered screens. All communication is standard HTTP with bearer token auth.

Base URL: https://sleek.design Auth: Authorization: Bearer $SLEEK_API_KEY on every /api/v1/ request Content-Type: application/json (requests and responses) CORS: Enabled on all /api/v1/ endpoints

Prerequisites: API Key

Create API keys at https://sleek.design/dashboard/api-keys. The full key value is shown only once at creation — store it in the SLEEK_API_KEY environment variable.

Required plan: Pro+ (API access is gated)

Key scopes

| Scope | What it unlocks | | ----------------- | ---------------------------- | | projects:read | List / get projects | | projects:write | Create / delete projects | | components:read | List components in a project | | chats:read | Get chat run status | | chats:write | Send chat messages | | screenshots | Render component screenshots |

Create a key with only the scopes needed for the task.

Security & Privacy

• Single host: All requests go exclusively to https://sleek.design. No data is sent to third parties.
• HTTPS only: All communication uses HTTPS. The API key is transmitted only in the Authorization header to Sleek endpoints.
• Minimal scopes: Create API keys with only the scopes required for the task. Prefer short-lived or revocable keys.
• Image URLs: When using imageUrls in chat messages, those URLs are fetched by Sleek's servers. Avoid passing URLs that contain sensitive content.

Handling high-level requests

When the user says something like "design a fitness tracking app" or "build me a settings screen":

1. Create a project if one doesn't exist yet (ask the user for a name, or derive one from the request)
2. Send a chat message describing what to build — you can use the user's words directly as message.text; Sleek's AI interprets natural language
3. Follow the screenshot delivery rule below to show the result

You do not need to decompose the request into screens first. Send the full intent as a single message and let Sleek decide what screens to create.

Screenshot delivery rule

After every chat run that produces screen_created or screen_updated operations, always take screenshots and show them to the user. Never silently complete a chat run without delivering the visuals.

When screens are created for the first time on a project (i.e. the run includes screen_created operations), deliver:

1. One screenshot per newly created screen (individual componentIds: [screenId])
2. One combined screenshot of all screens in the project (componentIds: [all screen ids])

When only existing screens are updated, deliver one screenshot per affected screen.

Use background: "transparent" for all screenshots unless the user explicitly requests otherwise.

Quick Reference — All Endpoints

| Method | Path | Scope | Description | | -------- | --------------------------------------- | ----------------- | ----------------- | | GET | /api/v1/projects | projects:read | List projects | | POST | /api/v1/projects | projects:write | Create project | | GET | /api/v1/projects/:id | projects:read | Get project | | DELETE | /api/v1/projects/:id | projects:write | Delete project | | GET | /api/v1/projects/:id/components | components:read | List components | | POST | /api/v1/projects/:id/chat/messages | chats:write | Send chat message | | GET | /api/v1/projects/:id/chat/runs/:runId | chats:read | Poll run status | | POST | /api/screenshots | screenshots | Render screenshot |

All IDs are stable string identifiers.

Endpoints

Projects

List projects

GET /api/v1/projects?limit=50&offset=0
Authorization: Bearer $SLEEK_API_KEY

Response 200:

{
  "data": [
    {
      "id": "proj_abc",
      "name": "My App",
      "slug": "my-app",
      "createdAt": "2026-01-01T00:00:00Z",
      "updatedAt": "..."
    }
  ],
  "pagination": { "total": 12, "limit": 50, "offset": 0 }
}

Create project

POST /api/v1/projects
Authorization: Bearer $SLEEK_API_KEY
Content-Type: application/json

{ "name": "My New App" }

Response 201 — same shape as a single project.

Get / Delete project

GET    /api/v1/projects/:projectId
DELETE /api/v1/projects/:projectId   → 204 No Content

Components

List components

GET /api/v1/projects/:projectId/components?limit=50&offset=0
Authorization: Bearer $SLEEK_API_KEY

Response 200:

{
  "data": [
    {
      "id": "cmp_xyz",
      "name": "Hero Section",
      "activeVersion": 3,
      "versions": [{ "id": "ver_001", "version": 1, "createdAt": "..." }],
      "createdAt": "...",
      "updatedAt": "..."
    }
  ],
  "pagination": { "total": 5, "limit": 50, "offset": 0 }
}

Chat — Send Message

This is the core action: describe what you want in message.text and the AI creates or modifies screens.

POST /api/v1/projects/:projectId/chat/messages?wait=false
Authorization: Bearer $SLEEK_API_KEY
Content-Type: application/json
idempotency-key: <optional, max 255 chars>

{
  "message": { "text": "Add a pricing section with three tiers" },
  "imageUrls": ["https://example.com/ref.png"],
  "target": { "screenId": "scr_abc" }
}

| Field | Required | Notes | | ------------------------ | -------- | --------------------------------------------- | | message.text | Yes | 1+ chars, trimmed | | imageUrls | No | HTTPS URLs only; included as visual context | | target.screenId | No | Edit a specific screen; omit to let AI decide | | ?wait=true/false | No | Sync wait mode (default: false) | | idempotency-key header | No | Replay-safe re-sends |

Response — async (default, wait=false)

Status 202 Accepted. result and error are absent until the run reaches a terminal state.

{
  "data": {
    "runId": "run_111",
    "status": "queued",
    "statusUrl": "/api/v1/projects/proj_abc/chat/runs/run_111"
  }
}

Response — sync (wait=true)

Blocks up to 300 seconds. Returns 200 when completed, 202 if timed out.

{
  "data": {
    "runId": "run_111",
    "status": "completed",
    "statusUrl": "...",
    "result": {
      "assistantText": "I added a pricing section with...",
      "operations": [
        { "type": "screen_created", "screenId": "scr_xyz", "screenName": "Pricing" },
        { "type": "screen_updated", "screenId": "scr_abc" },
        { "type": "theme_updated" }
      ]
    }
  }
}

Chat — Poll Run Status

Use this after async send to check progress.

GET /api/v1/projects/:projectId/chat/runs/:runId
Authorization: Bearer $SLEEK_API_KEY

Response — same shape as send message data object:

{
  "data": {
    "runId": "run_111",
    "status": "queued",
    "statusUrl": "..."
  }
}

When completed successfully, result is present:

{
  "data": {
    "runId": "run_111",
    "status": "completed",
    "statusUrl": "...",
    "result": {
      "assistantText": "...",
      "operations": [...]
    }
  }
}

When failed, error is present:

{
  "data": {
    "runId": "run_111",
    "status": "failed",
    "statusUrl": "...",
    "err