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

@artificialanlys:

@artificialanlys 2026-09-03

Context & Ripple Effects

Meta had already moved Muse Spark from a public API preview for US developers in July to a 54 score in August, tied for third among US labs in Artificial Analysis's ranking. The 62 result marks a measurable jump in that benchmark, though partner access remains limited.

The model family already powers queries in Meta AI and its shopping mode, while Meta has said it plans an open-source release of a Muse Spark version. That makes benchmark gains relevant not only to model buyers but also to Meta's existing product distribution.

First-order effects

Partners in the limited preview can assess Meta's higher-scoring max-reasoning model, while broader developer access has not been announced.
Meta moves from the 54 score recorded for Muse Spark 1.2 to 62, with only Fable 5.1 and Opus 5 ranked ahead on the stated index.

Second-order effects

Fable 5.1 and Opus 5 retain their lead on the index, but Meta's jump makes the benchmark comparison tighter for partners choosing among frontier reasoning models.
Meta's earlier integration of Muse Spark into Meta AI queries and shopping mode gives the company a route to apply model improvements across product surfaces if it deploys this version or its capabilities there.

Third-order effects

If successive score gains translate from partner previews into broad releases, frontier reasoning competition becomes less concentrated among the two models presently ahead of Muse Spark 1.3.
The combination of restricted high-end access, public APIs, planned open-source releases, and consumer-product distribution points toward differentiated release channels rather than a single model-access strategy.

The trend: Frontier AI labs are competing on rapid reasoning-model improvements while using distinct channels—partner previews, APIs, open releases, and owned products—to turn capability into adoption.

Discussion

@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
@udiwertheimer Udi Wertheimer on x
what is even the point of anthropic anymore
@zephyr_z9 @zephyr_z9 on x
Very impressive
@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..
@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…
@quinnypig Corey Quinn on x
Meta casting shade at Google in AI is a playground slapfight outside a MMA championship.
@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…
@chrisgpt Chris on x
We're starting to see the fruits of Metas massive spend. So happy to see FAIR get its footing.
@bnjmn_marie Benjamin Marie on x
Google was ahead only a few hours. And Meta will release the weights.
@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…
@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.
@angaisb_ Angel on x
Not Meta mogging Gemini 3.8 Flash the same day lmao [image]
@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
@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%)…
@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!
@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.
@finkd Mark Zuckerberg on x
Mark Zuckerberg says Meta's Watermelon model and Muse Spark open weights are “coming soon”
@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.
@alexandr_wang Alexandr Wang on x
for a single dime look at what muse spark can give you
@dryangsong Yang Song on x
Muse Spark 1.3 is here! The leap from 1.0 to 1.3 is nothing short of a miracle, and it took a lot of magic to make it happen. So proud of our team of magicians who sparked this incredible leap. And we are just getting started!
@alexandr_wang Alexandr Wang on x
muse spark 1.3 + muse code evals competitively with Claude code + opus 5 and Claude code + fable 5
@ashvinair Ashvin Nair on x
I recently joined the science of reasoning team at Meta! AI progress is moving faster than anyone can adjust to. I'm finding the goal of bringing personal superintelligence to everyone — AI that's positive and useful in people's lives worldwide — to be very motivating. Go try Mus…
@alexandr_wang Alexandr Wang on x
i really hate to say it, but... gemini who? 🏎️💨
@deryatr_ Derya Unutmaz on x
I wanted to try something quick with Muse Spark 1.3, so I had it build this pirate platformer. It was incredibly fast and worked flawlessly at one-shot! Now I'm enhancing the artwork, sprites and adding new levels 😊This is such a fun coding model, it just works, fast and cheap!
@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]
@alexandr_wang Alexandr Wang on x
underrated result of muse spark 1.3 try it out with muse code: curl -fsSL https://dev.meta.ai/... | bash
@aiatmeta @aiatmeta on x
We're excited to release Muse Spark 1.3 with improved performance on agentic and coding tasks, and a focus on real-world usability. Key capabilities: → Sustains longer-horizon work across multiple workflows in a single thread → More actively collaborates with users: it asks clari…
@edwardsun0909 Zhiqing Sun on x
We posttrained avocado again and enabled better test-time scaling. It's significantly better than its predecessor in all capabilities!
@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 …
@openrouter @openrouter on x
Muse Spark 1.3 is now available on OpenRouter! Built for long-running agentic, multi-agent, and coding workflows. It tracks what it learns, handles conflicting inputs, and asks for clarification or confirmation when needed. Use it now: https://openrouter.ai/...
@mihawkxxxxx @mihawkxxxxx on x
@DanDr1s Incredible Minecraft from muse spark 1.3 cost 10 cents
@rihardjarc Rihard Jarc on x
Wow, $META full Scorched-Earth Strategy with this AI model pricing. Nobody wants to have Zuck as a competitor.

Chronicles