Muse Spark 1.3

What is Muse Spark 1.3?

Muse Spark 1.3 is Meta’s model for agentic and coding work at scale, released on 2 September 2026 on Meta Model API and in Muse Code. Metas Ankündigung says it sustains long, multi-step work better than earlier Muse Spark models, and that in comparisons by Meta engineers it used about 20% fewer tool calls and 25% fewer tokens than Muse Spark 1.2. It accepts text, images, video, audio and PDF, returns text, has a 1,048,576-token context window and supports reasoning effort from minimal to max (default high). Meta’s docs recommend it for new work but warn that audio understanding on 1.3 is not fully supported; use Muse Spark 1.2 for audio.

In Standard mode it costs $1.25 per million input tokens, $0.15 for cached input and $4.25 per million output tokens, with no long-context premium. Contributor mode (muse-spark-1.3-contributor) drops that to $0.10, $0.002 and $0.20, but Meta may then use your prompts, code, files and the model’s responses to train future Meta models, and the max reasoning level is not available. Web search grounding adds $2.50 per 1,000 queries (see Meta’s pricing page).

Muse Spark sits in the middle of Meta’s lineup: Muse Wonder ($4 / $20, in preview) is Meta’s most capable model, and Muse Ember ($0.10 / $0.50 for requests up to 200K input tokens) handles high-volume sub-tasks. Muse Spark Open is a separate open-weight release (816B total, 42B active parameters); Muse Spark 1.3 itself is a hosted model without public weights. Meta’s Model API lists no Llama models, so for open Llama weights see Llama 4 Maverick, and compare monthly costs with the KI-API-Kostenrechner.