Meta rolls out Muse Spark 1.3 in Muse Code and Meta Model API, saying it significantly improves coding and agentic performance, at the same price as Spark 1.2

Meta on Wednesday released Muse Spark 1.3, an update it says significantly improves performance in coding and agentic tasks.

Axios 2026-09-02 Ina Fried

Context & Ripple Effects

Muse Spark moved from powering Meta AI queries and shopping mode in April to a public API preview for its 1.1 coding upgrade in July. Meta then made Spark 1.2 the engine of the Muse Code terminal-agent beta in August, tying model releases directly to a developer work surface.

Spark 1.3 extends that cadence across both Muse Code and the Meta Model API without raising the Spark 1.2 price. Artificial Analysis places its max-reasoning variant at 62 on its Intelligence Index, behind Fable 5.1 and Opus 5, giving Meta a concrete external comparison alongside its own performance claims.

First-order effects

Muse Code users and Meta Model API customers gain access to Meta’s claimed coding and agentic improvements at their existing Spark 1.2 token rates.
Meta can update the model beneath its coding harness and API endpoint while preserving the price point established for Spark 1.2.

Second-order effects

Existing Spark 1.2 customers face a lower cost-per-useful-task threshold if the claimed gains reduce retries or improve completion on coding and agent workflows.
The paired Muse Code and API rollout makes Meta’s model quality more consequential for developers choosing between an integrated coding surface and a model endpoint.

Third-order effects

Repeated capability upgrades at unchanged token pricing push coding-agent competition toward delivered task performance rather than headline model access price.
If Meta continues coupling Muse models to both its own work surface and API, model providers will increasingly compete through the execution environments that turn inference into completed work.

The trend: Coding-model vendors are using stable API pricing and integrated agent surfaces to compete on the cost and reliability of completed developer tasks.

Discussion

@alexandr_wang Alexandr Wang on x
i really hate to say it, but... gemini who? 🏎️💨
@arena @arena on x
Muse Spark 1.3 by @AIatMeta is now in the Arena! Bring your toughest prompts and start voting. Scores coming soon. In Agent Arena, we measure models on millions of real-world, long-horizon agentic tasks. Models can access web search, filesystem, and terminal tools to complete com…
@artificialanlys @artificialanlys on x
Muse Spark 1.3 with max reasoning, in limited preview for partners, scores 62 on the Artificial Analysis Intelligence Index, behind only Fable 5.1 and Opus 5
@rihardjarc Rihard Jarc on x
Wow, $META full Scorched-Earth Strategy with this AI model pricing. Nobody wants to have Zuck as a competitor.
@pratanchandani Prashant Ratanchandani on x
Muse Spark 1.3 is ready for you in the Meta Model API and in our coding harness. We've worked hard on this model and it is a huge leap forward on coding and agentic workloads, and remains at the frontier of intelligence at a very competitive price. The contributor version is up a…
@rihardjarc Rihard Jarc on x
$META Muse Spark 1.3 is 1st place ln DeepSWE with ahead of Fable 5 and GPT-5.6 Sol and this even Watermelon yet. $META trajectory is really good.
@justingorya Justin on x
META COOOOOOKED!!! Wow. Meta muse spark 1.3 was just released and it seems to be amazing?! used my 2 custom skills and got this in a oneshot. The whole Website was a simple prompt and oneshot. Muse spark 1.3 is creative and good at frontend. approved.
@eltokh7 Khaled on x
Very impressive as usual from @Meta and @alexandr_wang! Muse Spark 1.3 debuts as the 3rd top performing model in Stata Benchmark. It beats EVERY model except Claude Fable
@levie Aaron Levie on x
This week is absolutely nuts for AI releases, and now a major new model update from Muse. We appear to be reaching escape velocity in capability progress. If this thing gets released as open weights it completely changes the dynamic of US open weights competitiveness.
@shengjia_zhao Shengjia Zhao on x
Today we're releasing Muse Spark 1.3, our strongest model for agentic and coding tasks in the spark model line. It's designed to support longer-horizon work, excel in agentic tasks, and follow complex instructions more reliably than previous models. Muse Spark 1.3 is available to…
@alexandr_wang Alexandr Wang on x
2/It's a step up on reasoning and coding. compared to Muse Spark 1.2, Muse Spark 1.3 wastes fewer turns, uses ~20% fewer tool calls, ~25% fewer tokens, and holds onto requirements well during long-horizon tasks.
@kimmonismus @kimmonismus on x
wtf Muse Spark 1.3 It has achieved first place in DeepSWE with 75.4%, even ahead of GPT-5.6 Sol and Fable 5. What's going on here?!
@alexandr_wang Alexandr Wang on x
1/ today we're releasing muse spark 1.3—available in muse code & the meta model api. this is our most capable model yet—frontier performance almost too cheap to meter. much stronger at agentic and coding with better usability. we think users will really notice the jump.
@metafordevs @metafordevs on x
Muse Spark 1.3 is now available in Muse Code and Meta Model API. It's tuned for the agentic builds developers actually ship, including long-running, multi-agent workflows. 🧵👇(1/4) [video]
@maria_rcks Maria on x
SOTA IN DEEPSWE???? Wtfffff
@synthwavedd Leo on x
Muse Spark 1.3 is here! Benchmarks look pretty good, with a SoTA score on DeepSWE v1.1 Proving to be a very busy week
@andrewcurran_ Andrew Curran on x
Muse Spark 1.3 is showing up live on the Meta API and in other places, my friend spotted it an hour ago. 1.3 appears to be rolling out now, the official announcement, and posts from Mark and Alexandr, are probably incoming.
@cheatyyyy @cheatyyyy on x
Meta Muse Spark 1.3 benchmarks are out! It's SOTA Long Context and DeepSWE v1.1!!!
r/LocalLLaMA r on reddit
Muse Spark open weights coming soon
@dandr1s Dan on x
Meta's Muse Spark 1.3 just scored 62 on Artificial Analysis' Intelligence Index. That ties Claude Fable 5, but Muse costs 8x less for input and nearly 12x less for output. It also scores above GPT-5.6 Sol, Grok 4.6, Kimi K3, and Gemini 3.8 Flash. Meta is suddenly in the top tier …
@patricktoulme Patrick C Toulme on x
$META I predict will imminently shutoff Anthropic and OpenAI model access for employees. This may very well affect the Anthropic and OpenAI IPOs. Watermelon will be Fable class. This is 100% proof that Meta's experiment of having employees generate tens of thousands of RL envs wo…
@deryatr_ Derya Unutmaz on x
This is just crazy! @metaai just released Muse Spark 1.3 that looks better than GPT-5.6 Sol max and near Opus 5 max for coding AND at less than a third of the price: $1.25 input / $4 output per million tokens! Meta finally caught up to frontier AI and became super competitive. 😲
@mehulmpt Mehul Mohan on x
Muse Spark 1.3 contributor pricing is just mind-blowingly unreal its literally deepseek pricing moment from a US AI lab
@da7_tech @da7_tech on x
This is insane. If real-world performance actually matches these benchmarks, we're talking about a complete game changer in AI.
@beffjezos @beffjezos on x
The AI Capex of Meta is starting to pay off bigtime
@ttunguz Tomasz Tunguz on x
Enormously important for US to have SoTA open models
@zephyr_z9 @zephyr_z9 on x
Meta has a very strong post training pipeline now
@yashvarpatel Yash Patel on x
Muse Spark 1.3 is now live! With solid improvements on coding and agentic work including computer use. Please give it a try and let us know what you think.
@xiangyue96 Xiang Yue on x
Muse Spark 1.3 is our most capable model yet, with major improvements to usability, including complex instruction following and reduced hallucinations in agentic tasks. 🍉 and open-weight Muse Spark are coming soon!
@eliebakouch Elie on x
long context benchmark (MRCR) going crazy, very interesting would be great to have other benchmarks such as graphwalks for long context and release test time scaling curves and not just raw benchmark scores in general
@mweinbach Max Weinbach on x
It's kind of funny that the cost of a good quality output from AI has dropped like 5-10x this summer
@shuchaobi @shuchaobi on x
We spent a lot more compute in grading to improve model behaviors such as laziness, instruction following, hedging, and other reward seeking and reward hacking behaviors. As a result the model's usability is vastly improved. Please give it a try and let us know what you think.
@lichangchen2 Lichang Chen on x
We've experimented some breakthrough training methods and turns out that it works. Try the model on Muse Code harness! We appreciate any feedback from you.
@alexandr_wang Alexandr Wang on x
check out our new muse spark 1.3 model!
@matthewberman Matthew Berman on x
Ok I see you Meta
@kimmonismus @kimmonismus on x
Today meta chose war with google. But hey, let them fight it out. That just means development will accelerate even further. By the way: I can't imagine OpenAI waiting long to reclaim the top spot in DeepSWE.
@mattdeitke Matt Deitke on x
The jump for Muse Spark 1.3 on AA Index is quite strong! Only behind recent Anthropic models at this point. Much stronger models coming soon! 🍉🥳
@xeophon Florian Brand on x
Gemini 3.8 held a spot at the pareto frontier for *checks notes* 3.5 hours
@zephyr_z9 @zephyr_z9 on x
Very impressive
@angaisb_ Angel on x
Not Meta mogging Gemini 3.8 Flash the same day lmao [image]
@altryne Alex Volkov on x
Damn, gloves are off! Unreleased Meta Muse Spark with max reasoning is beating even Fable 5, while the xhigh that is available, matches Grok 4.6 and GPT 5.6 sol on @ArtificialAnlys This is quite the statement from @AIatMeta 🔥 Busy weeks ahead of us!
@bnjmn_marie Benjamin Marie on x
Google was ahead only a few hours. And Meta will release the weights.
@haider1 Haider on x
how tf Meta is moving this insanely fast needs to be studied they went from looking weirdly behind in the AI race to suddenly shipping at a pace that feels completely different
@chrisgpt Chris on x
We're starting to see the fruits of Metas massive spend. So happy to see FAIR get its footing.
@spac89 @spac89 on x
How the hell is Muse Spark 1.3 Max better than Fable 5? I genuinely don't think anyone saw this coming..
@udiwertheimer Udi Wertheimer on x
what is even the point of anthropic anymore
@artificialanlys @artificialanlys on x
Muse Spark 1.3 (max) scores 52% on Tau3-Bench Banking, the new #1 performer on this evaluation. Muse Spark 1.3 (xhigh) scores 47%, level with Claude Fable 5.1 (max, 47%) and GLM-5.3-Flash (47%) and behind its sibling in addition to e.g. Qwen3.8 Max (51%), Grok 4.6 (high, 51%), an…
@artificialanlys @artificialanlys on x
The gains for Muse Spark 1.3 (xhigh) and Muse Spark 1.3 (max) over Muse Spark 1.2 on the Artificial Analysis Intelligence Index are concentrated in agentic evaluations: GDPval-AA v2 +94 and +139 Elo (1615 to 1709 and 1754), Terminal-Bench 2.1 +5 and +6 points (80% to 85% and 86%)…
@artificialanlys @artificialanlys on x
Muse Spark 1.3 (xhigh) is the most cost-efficient model at its intelligence level: $0.55 per Intelligence Index task at Meta's unchanged $1.25/$4.25 per 1M token pricing. No model scoring 59 or above costs less per task. The nearest are Gemini 3.8 Flash (high, 59, $0.58), GPT-5.6…
@deryatr_ Derya Unutmaz on x
My early testing results of @Meta Muse Spark 1.3 for coding are really good! I'll share some examples soon. I recommend trying it out. They also have a $5/month subscription with relatively generous prompting limits. I'm using the terminal CLI, it'd be good to have their own IDE.
@emostaque Emad on x
meta, the frontier ai lab?
@llmjunky @llmjunky on x
META IS BACK BABY. 88 on TB 2.1 75 on DeepSWE! Wow.
@hesamation @hesamation on x
Muse Spark 1.3 is now the top non-Anthropic model on Artificial Analysis Intelligence Index: > same score as Fable 5 > with 12x cheaper output tokens ($4.25/M vs $50/M) > just 1 point behind Opus 5, 4 points behind Fable 5.1 from YESTERDAY. I'm especially curious about cost per …
@nateberkopec Nate Berkopec on x
Muse Spark 1.3 xhigh is frontier for time/task AND cost/task. We have a new frontier human-in-the-loop coding model. Gemini 3.8-flash is slightly cheaper but also slower than 3.7, so no changes there.
@kimmonismus @kimmonismus on x
It's worth really grasping this: in a very short time, the race between OpenAI and Anthropic has turned into a contest involving OpenAI, Anthropic, xAI, and Meta, and Google is back in the mix, too. They are all on (mostly) equal footing, with little difference between them even…

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