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Muse Spark 1.3

Name: Muse Spark 1.3
Brand: Meta
Price: 1.25 USD
Availability: InStock

Muse Spark 1.3 is a reasoning model by Meta with vision, function calling, prompt caching, structured output — designed for complex, multi-step problem solving where accuracy matters more than speed. It supports a 1M token context window with up to 944K tokens of output. Priced at $1.25 per million input tokens and $4.25 per million output tokens. Access Muse Spark 1.3 through Inworld Router with OpenAI SDK compatibility, built-in failover, and intelligent routing across providers.

→Function CallingReasoningPrompt CachingResponse SchemaVisionreasoningCapabilityresponseFormatCapability

Use This Model

Step 1 — Create Router

curl --location 'https://api.inworld.ai/router/v1/routers' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "name": "compare-frontier-models",
  "defaultRoute": {
    "route_id": "default",
    "variants": [
      {
        "variant": {
          "variant_id": "meta/muse-spark-1.3-a",
          "model_id": "meta/muse-spark-1.3"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo-b",
          "model_id": "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo"
        },
        "weight": 33
      },
      {
        "variant": {
          "variant_id": "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo-c",
          "model_id": "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo"
        },
        "weight": 34
      }
    ]
  }
}'

import requests

response = requests.post(
    "https://api.inworld.ai/router/v1/routers",
    headers={
        "Authorization": "Basic <your-api-key>",
        "Content-Type": "application/json",
    },
    json={
        "name": "compare-frontier-models",
        "defaultRoute": {
            "route_id": "default",
            "variants": [
                {
                    "variant": {
                        "variant_id": "meta/muse-spark-1.3-a",
                        "model_id": "meta/muse-spark-1.3"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo-b",
                        "model_id": "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo"
                    },
                    "weight": 33
                },
                {
                    "variant": {
                        "variant_id": "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo-c",
                        "model_id": "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo"
                    },
                    "weight": 34
                }
            ]
        }
    },
)
print(response.json())

const response = await fetch(
  "https://api.inworld.ai/router/v1/routers",
  {
    method: "POST",
    headers: {
      Authorization: "Basic <your-api-key>",
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      name: "compare-frontier-models",
      defaultRoute: {
        route_id: "default",
        variants: [
          {
            variant: {
              variant_id: "meta/muse-spark-1.3-a",
              model_id: "meta/muse-spark-1.3",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo-b",
              model_id: "deepinfra/meta-llama/Llama-3.3-70B-Instruct-Turbo",
            },
            weight: 33,
          },
          {
            variant: {
              variant_id: "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo-c",
              model_id: "deepinfra/meta-llama/Meta-Llama-3.1-8B-Instruct-Turbo",
            },
            weight: 34,
          },
        ],
      },
    }),
  }
);
const data = await response.json();
console.log(data);

Step 2 — Chat Completion

curl --location 'https://api.inworld.ai/v1/chat/completions' \
--header 'Authorization: Basic <your-api-key>' \
--header 'Content-Type: application/json' \
--data '{
  "model": "inworld/compare-frontier-models",
  "messages": [{"role": "user", "content": "Hello!"}]
}'

Muse Spark 1.3 pricing and providers

Access Muse Spark 1.3 through meta via Inworld Router or Realtime API. By using the AI provider(s) below you acknowledge you reviewed and agree to their terms listed in the Legal section under the AI provider's name.

							Capabilities	Input modalities	Output modalities
meta	$1.25	$4.25	$0.15	—	1M	943.7K	+4

Prices in USD per 1M tokens.

Other Meta models available through Inworld

Compare Muse Spark 1.3 with other Meta models available through Inworld Router or Realtime API.

							Capabilities
Llama 3.3 70B Instruct Turbo	$0.10	$0.32	—	—	131.1K	131.1K
Meta Llama 3.1 8B Instruct Turbo	$0.02	$0.04	—	—	131.1K	131.1K
Muse Spark 1.3 Contributor	$0.10	$0.20	$0.002	—	1M	943.7K	+4