Claude Opus 4.8 vs Muse Spark 1.1

Anthropic · US  |  Meta · US · Updated June 2026

Quick verdict

Pick Claude Opus 4.8 for agentic coding and multi-file debugging or long autonomous tasks. Pick Muse Spark 1.1 for scaled tool use — 88.1 on mcp atlas, ahead of opus 4.8 and gpt-5.5 (vendor-reported) or subagent orchestration — trained to run as a main agent or a subagent that escalates when stuck. On a tight budget at scale, Muse Spark 1.1 is the value pick.

Claude Opus 4.8 (Anthropic) and Muse Spark 1.1 (Meta) are two of the models people most often weigh against each other in 2026. Claude Opus 4.8 is the agentic-coding and judgment leader — highest SWE-Bench Pro score ever recorded at launch. Muse Spark 1.1 is meta's first paid, closed-weight frontier model — class-leading agentic tool use at a quarter of rivals' price, but it trails on coding. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Opus 4.8Muse Spark 1.1
ProviderAnthropic (US) Meta (US)
ReleasedMay 28, 2026 July 9, 2026
Context window1M (~1,500 pages) 1M (~1,573 pages)
Price (in/out)$5/$25 per 1M tokens $1.25/$4.25 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, video, code
SWE-Bench Verified88.6% Not published
MRCR v2 @ 1MNot published 54.1%

Who wins what

Agentic coding and multi-file debugging

Claude Opus 4.8

Muse Spark 1.1 is comparatively weak here — not the coding leader its launch framing implied — Meta's own report concedes it trails Opus 4.8 and GPT-5.5 on every coding benchmark

Long autonomous tasks

Claude Opus 4.8

Claude Opus 4.8 lists long autonomous tasks among its strengths; Muse Spark 1.1 does not.

Honest uncertainty flagging

Claude Opus 4.8

Claude Opus 4.8 lists honest uncertainty flagging among its strengths; Muse Spark 1.1 does not.

Scaled tool use — 88.1 on MCP Atlas, ahead of Opus 4.8 and GPT-5.5 (vendor-reported)

Muse Spark 1.1

At $1.25/$4.25 per 1M tokens it undercuts Claude Opus 4.8 ($5/$25 per 1M tokens), and that gap compounds at volume.

Subagent orchestration — trained to run as a main agent or a subagent that escalates when stuck

Muse Spark 1.1

Meta's first paid, closed-weight frontier model — class-leading agentic tool use at a quarter of rivals' price, but it trails on coding — and it runs cheaper at $1.25/$4.25 per 1M tokens.

Professional agentic work — 54.7 on JobBench, a wide margin over rivals (vendor-reported)

Muse Spark 1.1

Meta's first paid, closed-weight frontier model — class-leading agentic tool use at a quarter of rivals' price, but it trails on coding — and it is the newer of the two.

Lowest cost at scale

Muse Spark 1.1

At $1.25/$4.25 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

Muse Spark 1.1

At $1.25/$4.25 per 1M tokens it undercuts Claude Opus 4.8, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Muse Spark 1.1

Larger 1M window fits more in one prompt.

Anyone whose priority is agentic coding and multi-file debugging

Claude Opus 4.8

It is specifically built for that.

Anyone whose priority is scaled tool use — 88.1 on mcp atlas, ahead of opus 4.8 and gpt-5.5 (vendor-reported)

Muse Spark 1.1

That is its strongest area.

Claude Opus 4.8: where it fits

The agentic-coding and judgment leader — highest SWE-Bench Pro score ever recorded at launch. Released May 28, 2026 by Anthropic, it is built for agentic coding and multi-file debugging, long autonomous tasks, honest uncertainty flagging, and professional writing and reasoning.

Its trade-offs are real: highest per-token price of the frontier tier, and not the cheapest for high-volume work. At $5 in / $25 out per million tokens, it sits in the premium price band.

Muse Spark 1.1: where it fits

Meta's first paid, closed-weight frontier model — class-leading agentic tool use at a quarter of rivals' price, but it trails on coding. Released July 9, 2026 by Meta, it is built for scaled tool use — 88.1 on MCP Atlas, ahead of Opus 4.8 and GPT-5.5 (vendor-reported), subagent orchestration — trained to run as a main agent or a subagent that escalates when stuck, professional agentic work — 54.7 on JobBench, a wide margin over rivals (vendor-reported), and managing its own context: it compacts the 1M window mid-run instead of relying on external windowing.

Its trade-offs: not the coding leader its launch framing implied — Meta's own report concedes it trails Opus 4.8 and GPT-5.5 on every coding benchmark, the 1M window oversells its recall: 54.1 on MRCR v2 at 1M against GPT-5.5's 74.0, closed weights end the free, self-hostable Llama path — this is the first model Meta has charged for, and uS-only public preview behind a waitlist, and every benchmark is vendor-reported with no third-party replication. At $1.25 in / $4.25 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Claude Opus 4.8 and Muse Spark 1.1 overlap enough that the right pick depends on your specific job. Muse Spark 1.1 costs less per token; Muse Spark 1.1 holds the larger context; and each leads in its own area — Claude Opus 4.8 for agentic coding and multi-file debugging, Muse Spark 1.1 for scaled tool use — 88.1 on mcp atlas, ahead of opus 4.8 and gpt-5.5 (vendor-reported). Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Opus 4.8 and Muse Spark 1.1 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Opus 4.8 or Muse Spark 1.1 better for coding?

Public SWE-Bench figures are not available for Muse Spark 1.1, so the honest test is your own repository — run an identical real bug through both. By design, Claude Opus 4.8 leans toward agentic coding and multi-file debugging while Muse Spark 1.1 leans toward scaled tool use — 88.1 on mcp atlas, ahead of opus 4.8 and gpt-5.5 (vendor-reported), and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Opus 4.8 or Muse Spark 1.1?

Muse Spark 1.1 is cheaper — $5/$25 per 1M tokens vs $1.25/$4.25 per 1M tokens, roughly 4× apart on input.

Which has the bigger context window?

Effectively neither — 1M vs 1M is a difference of a few percent. Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Claude Opus 4.8 and Muse Spark 1.1 together?

Yes — a multi-model platform like LumiChats gives you Claude Opus 4.8, Muse Spark 1.1 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Opus 4.8 or Muse Spark 1.1?

Muse Spark 1.1 — released July 9, 2026, about 42 days after Claude Opus 4.8.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.