For developers running long coding agents, the Contributor tier is remarkably cheap; Meta lists no countries for the API.

Kenning's take

What it does

Muse Spark 1.3 is the latest Muse Spark model, tuned for long-running agent work and coding. Meta says it asks clarifying questions when a prompt is unclear, confirms before consequential actions, follows long instructions more reliably and handles several tasks in one thread. It is available in Muse Code and the Meta Model API, including a max reasoning level, with a 1 million token context window.

  • Max reasoning effort level
  • 1 million token context window
  • Asks clarifying questions and confirms risky actions
  • Better multitasking in one long thread
  • Cheaper Contributor tier that allows training on prompts

Who it suits. Developers building coding and agent tools on Meta's models.

Key facts

Category
AI models
Part of
Meta AI
Made by
Meta (Meta Superintelligence Labs)
Released
2 September 2026
How to get it
in Muse Code and the Meta Model API as muse-spark-1.3 (Standard) or muse-spark-1.3-contributor (discounted)
Works on
API, CLI
API price
$1.25 per million input tokens, $4.25 per million output, $0.15 cached input (Standard tier); Contributor tier $0.10 input and $0.20 output in exchange for allowing training on prompts

FAQ

When was Muse Spark 1.3 released?

Meta released it on 2 September 2026.

How much does Muse Spark 1.3 cost?

$1.25 per million input tokens and $4.25 per million output on the Standard tier, or $0.10 and $0.20 on the Contributor tier, which lets Meta train on prompts.

Where can I use Muse Spark 1.3?

In Muse Code and through the Meta Model API at dev.meta.ai.

Facts from the maker's own pages and the sources listed. Checked 2026-10-11.