`generate_thumbnail`

Generation write

What it does

Builds three distinct thumbnail variants using Replicate FLUX (preferred provider: black-forest-labs/flux-schnell, native multi-aspect, ~$0.003/image). Falls back to DALL-E 3 (OpenAI) or fal.ai Flux if only those keys are set. One landscape (16:9), one portrait (9:16), one square (1:1) — each with a different style descriptor.

PNGs are stored at <slug>/thumbnails/<content_id>/variant-N.png and the response exposes a per-variant URL plus the exact prompt used.

Input schema

Name	Type	Required	Default	Description
id	string	required	`—`	Content id (uses `title` + `brand` for prompt building).
style_hint	string	optional	`—`	Override the per-variant style. One of `cinematic`, `minimalist`, `energetic`.

Example call

json{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "generate_thumbnail",
    "arguments": {
        "id": "c_abc123",
        "style_hint": "minimalist"
    }
  }
}

Response shape

json{
  "ok": true,
  "content_id": "c_abc123",
  "provider": "replicate",
  "prompt_strategy": "Per-variant prompt built from title... + brand...",
  "variants": [
    {
      "id": "thumb_1",
      "url": "https://lumiqa.io/api/asset/your-slug%2Fthumbnails%2Fc_abc123%2Fvariant-1.png",
      "r2_key": "your-slug/thumbnails/c_abc123/variant-1.png",
      "aspect_ratio": "16:9",
      "style": "cinematic",
      "prompt_used": "Bold, high-contrast YouTube thumbnail..."
    }
  ]
}

Usage from Claude Desktop

prompt"Make me three thumbnails for c_abc123, all in minimalist style."

Usage from Python

pythonimport requests

LUMIQA = "https://lumiqa.io/mcp/your-slug"
HEADERS = {"Authorization": "Bearer lk_live_xxxxxxxxxxxx"}

r = requests.post(LUMIQA, headers=HEADERS, json={
    "jsonrpc": "2.0", "id": 1,
    "method": "tools/call",
    "params": {
        "name": "generate_thumbnail",
        "arguments": {"id": "c_abc123"}
    },
})
print(r.json())

Usage from Node

javascriptconst r = await fetch("https://lumiqa.io/mcp/your-slug", {
  method: "POST",
  headers: {
    "Authorization": "Bearer lk_live_xxxxxxxxxxxx",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    jsonrpc: "2.0", id: 1,
    method: "tools/call",
    params: {
      name: "generate_thumbnail",
      arguments: { id: "c_abc123" },
    },
  }),
});
const data = await r.json();
console.log(data);

Required env vars / integrations

BYO Keys (preferred): REPLICATE_API_TOKEN → flux-schnell native multi-aspect, ~$0.003 / image.
Fallback: OPENAI_API_KEY (DALL-E 3, fixed sizes, ~$0.04 / image) or FAL_API_KEY (fal.ai Flux).
R2 binding UPLOADS (managed by Lumiqa).
Optional APP_URL override for the returned asset URLs.
Typical latency: 8–14 s end-to-end for all 3 variants on Replicate.

Known limitations

Replicate FLUX schnell honors aspect_ratio natively (16:9, 9:16, 1:1). DALL-E 3 quantizes to (1792x1024, 1024x1792, 1024x1024) — pixel-perfect aspects require post-processing.
If only some variants fail, the tool still returns the successful ones with partial_failures populated.
Prompts intentionally exclude on-image text (overlay it client-side for proper typography).

generate_thumbnail