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Meta

Muse Spark 1.3

Muse Spark 1.3 is a multimodal reasoning model from Meta for long-running agentic, multi-agent, and coding workflows. It improves long-horizon agent collaboration, instruction following, and coding efficiency relative to Muse Spark 1.2.

Released
Sep 2 2026
Modality
Text + Image + Document + Audio + Video
Context
1M tokens
Price in / cached input / out
$1.25 / $0.15 / $4.25per 1M tokens

Quickstart

OpenAI-compatible: change the base URL, and the setup is complete.

from openai import OpenAI
import os

client = OpenAI(
    base_url="https://api.you.com/v1",
    api_key=os.environ["YOU_API_KEY"],
)

response = client.chat.completions.create(
    model="muse-spark-1.3",
    messages=[{"role": "user", "content": "Summarize this support ticket in two sentences."}],
)

print(response.choices[0].message.content)

Specifications

Technical details, capabilities, pricing, and data handling.

Model info

Input Modality
Text, Image, Document, Audio, Video
Output Modality
Text
Context Window
1M

Capabilities

Reasoning
Supported
Function calling
Supported
Structured outputs
Not supported
Web search grounding
Not supported

Pricing

Input
$1.25
Cached input
$0.15
Output
$4.25

Data handling

Zero data retention
Supported
No training on customer data
Supported
Regions
US

Providers

Access models through multiple providers with automatic routing and built-in failover.

Providers serving Muse Spark 1.3
ProviderZDRNo trainingRegion
You InferenceYesYes
US
MetaYesYes
US

When to use Muse Spark 1.3

Guidance based on the specifications and benchmarks on this page.

Best for

  • Long-horizon agentic codingMeta tuned it for long coding workflows; it scores 75.4% on DeepSWE v1.1 and 88.8% on Terminal-Bench 2.1 at max reasoning.
  • Retrieval across very long contextMeta reports 98% or higher on MRCR v2 needle retrieval at 256K–1M tokens.
  • Multi-step agent workflowsSustains long threads, gathers context from conflicting sources, corrects gaps in its plan, and asks for clarification when stuck.
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Consider alternatives for

  • You need maximum agentic capabilityMeta says Muse Wonder builds on larger, stronger base models and handles unfamiliar tasks better.
  • You need open weightsMuse Spark 1.3 weights are closed; Meta offers Muse Spark Open for self-hosting.

Benchmarks

Muse Spark 1.3 results alongside comparable models

Coding benchmark scores
BenchmarkMuse Spark 1.3MetaKimi K3Moonshot AIDeepSeek V4.1 FlashDeepSeekGLM 5.3Z.aiQwen3.8 MaxAlibabaMuse WonderMeta
Terminal-Bench 2.188.8%88.3%90.6%88.2%86.6%Not evaluated
DeepSWE v1.175.4%67.5%74.2%66.9%56.6%78.8%

Scores are self-reported by each model’s developer, so settings may vary between models. Sources: Muse Spark 1.3 (release post), Kimi K3 (Hugging Face), DeepSeek V4.1 Flash (Hugging Face), GLM 5.3 (Hugging Face), Qwen3.8 Max (Hugging Face), Qwen3.8 Max (release post), Muse Wonder (release post).

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