Muse Spark 1.2

Name: Muse Spark 1.2
Author: Meta

Meta · 2026-08-05

Muse Spark 1.2 is Meta's August 2026 coding-focused update to Muse Spark 1.1. It powers Muse Code and supports long-horizon software engineering and multimodal understanding.

Benchmark scores

Benchmark	Score
AA-Briefcase Elo	1344
AA-Briefcase v1.1 Elo	1325
AA-LCR v1.1	79.0
AA-Omniscience Index	27.2
Antidote: Everyday Edition	1028
APEX (Mercor)	23.7
APEX-Accounting	51.4
APEX-Accounting Pass@1	8.9
APEX-Agents 1.1	59.8
APEX-Agents 1.1 Pass@1	45.4
APEX-SWE	40.5
APEX-v1-extended	75.6
Arena Code WebDev — Brand & Marketing	1522
Arena Code WebDev — Consumer Product	1529
Arena Code WebDev — Content Creation Tools	1543
Arena Code WebDev — Data & Analytics	1518
Arena Code WebDev — Frontend	1532
Arena Code WebDev — Gaming	1561
Arena Code WebDev — HTML	1543
Arena Code WebDev — React	1525
Arena Code WebDev — Reference-Based Design	1553
Arena Code WebDev — Simulations	1516
Arena Text — Business, Management & Financial Ops (No Style Control)	1484
Arena Text — Chinese (No Style Control)	1506
Arena Text — Creative Writing (No Style Control)	1435
Arena Text — English (No Style Control)	1483
Arena Text — Entertainment, Sports & Media (No Style Control)	1443
Arena Text — Exclude Ties (No Style Control)	1491
Arena Text — Exclude Ties (Style Controlled)	1507
Arena Text — Expert (No Style Control)	1474