
Real head-to-head · same prompt, one shot
Muse Spark 1.2 vs Kilo Code
Meta's coding reasoning model — co-trained with its own agent, 1M-token window. vs Fable 5-class intelligence at ~59% less. The split-the-cost play.
What I tested — same prompt, two models
I run the same fixed prompt set through every new model the day it drops — same string, one shot, single HTML file out — and I score the result 0–10 on whether it ran, how close it hit the brief, and how good it looked. Below is what came out when I gave the exact same prompts to Muse Spark 1.2 and Kilo Code, side by side, on 0 shared tasks inside the Agent Operating System.
Both models were given identical prompts inside the Agent Operating System — no help, no iteration, no "best of N" tricks. I run each prompt once, save the HTML file the model produces, and score it 0–10 on whether it ran, how close it hit the brief, and how good it looked. The scoring is mine. The verdicts below are pulled from my source comparison guides at agentos.guide where I publish every score and the reasoning behind it.
Muse Spark 1.2 · Cloud coder via OpenRouter; the Muse Code agent (one-command install) is its native harness.
Kilo Code · Used inside Agent OS as a routing layer: Fable 5 generates the plan, cheaper models execute. Bench scoring pending a head-to-head comparison.
Side-by-side on 50 shared tasks
Click any cell to play that model's actual one-shot attempt. Medals are derived from my 0–10 scores per task (highest = 🥇, second = 🥈, third = 🥉).
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Strengths & weaknesses I logged
Muse Spark 1.2
Strengths
- Generative art & shader-feel scenes (fractal 8.7, aurora/galaxy/matrix/synthwave 8.6)
- Full app chrome one-shot (macOS-clone desktop 8.6)
- Fast one-shots — most builds landed in 45-80s
- 1M context for whole-repo work
Trade-offs
- 3D game worlds often render black/empty (dragonrealm 2.5, dogfight 3.0, doom 3.5)
- Open-world briefs collapse to HUD-only shells
- Reasoning tokens billed as output
Kilo Code
Strengths
- Kilo's own rubric: Fable 5 plan = 9.1/10, GPT-5.5 plan = 8.3/10 — Kilo isolates where the intelligence actually lives
- Plan quality stays high while execution cost drops
- Drop-in for Agent OS — Kilo Split framework already wired
Trade-offs
- Adds routing complexity — two model providers in one workflow
- No per-task goldiebench head-to-heads yet
Pricing & context — the spec sheet
| Spec | Muse Spark 1.2 | Kilo Code |
|---|---|---|
| Vendor | Meta | Kilo |
| Context window | 1,000,000 tokens | Varies — Kilo splits planning from execution across multiple models |
| Price | $1.25 in / $4.25 out per 1M | ~59% less than Fable 5 solo |
| Pricing detail | Meta's coding-optimized reasoning model, released 2026-08-05 beside the Muse Code agent. $0.15/1M cached input. Contributor tier is token-rate-limited in a rolling 5-hour window. Benched release-day via OpenRouter (meta/muse-spark-1.2, first-party listing); Opus 4.8 judged every real rendered poster, same rubric as the whole field. | Kilo Code is a routing layer that splits planning (heavy model) from execution (cheaper model) so you get Fable-5-class plans driving GPT-5.5-class builds. Total spend lands at ~59% less than running Fable 5 end-to-end. |
| Release | 2026-08-05 | 2026-06-16 |
| Bench coverage | 50/50 scored · avg 7.47/10 | 0/0 scored · avg — |
The verdict — which should you pick?
Not enough scored shared tasks yet for a head-to-head average. The live demos for both are on the matrix above — play them and form your own opinion.
If you only run one of these inside your stack, the head-to-head average above is the call. If you can run both, my honest play is to wire Muse Spark 1.2 and Kilo Code both into the Agent Operating System and dispatch each from the kanban by task type — generative-art visuals → Muse Spark 1.2, cost-conscious operators who run high-volume agent loops → Kilo Code. That's the same setup I run for the 4,000+ founders inside the AI Profit Boardroom.
FAQ — Muse Spark 1.2 vs Kilo Code
Which is better, Muse Spark 1.2 or Kilo Code?
On Goldie Bench, Muse Spark 1.2 averages no scored verdicts yet across the shared tasks, with 0 gold, 3 silver, 4 bronze overall. Kilo Code averages no scored verdicts yet, with 0 gold, 0 silver, 0 bronze. Not enough scored shared tasks yet to call a winner.
How much does Muse Spark 1.2 cost vs Kilo Code?
Muse Spark 1.2: Meta's coding-optimized reasoning model, released 2026-08-05 beside the Muse Code agent. $0.15/1M cached input. Contributor tier is token-rate-limited in a rolling 5-hour window. Benched release-day via OpenRouter (meta/muse-spark-1.2, first-party listing); Opus 4.8 judged every real rendered poster, same rubric as the whole field. Kilo Code: Kilo Code is a routing layer that splits planning (heavy model) from execution (cheaper model) so you get Fable-5-class plans driving GPT-5.5-class builds. Total spend lands at ~59% less than running Fable 5 end-to-end.
What's the context window for Muse Spark 1.2 vs Kilo Code?
Muse Spark 1.2 has a 1,000,000 tokens context window. Kilo Code has a Varies — Kilo splits planning from execution across multiple models context window.
When should I pick Muse Spark 1.2 over Kilo Code?
Pick Muse Spark 1.2 for: Generative-art visuals; Dashboard & app-shell one-shots; Long-context refactors (1M window). The trade-off is the weaknesses we logged on the bench: 3D game worlds often render black/empty (dragonrealm 2.5, dogfight 3.0, doom 3.5); Open-world briefs collapse to HUD-only shells; Reasoning tokens billed as output.
When should I pick Kilo Code over Muse Spark 1.2?
Pick Kilo Code for: Cost-conscious operators who run high-volume agent loops; Multi-step workflows where the plan is the expensive part; Teams already paying for Fable 5 who want to keep the plan but drop the execution bill. The trade-off is the weaknesses we logged on the bench: Adds routing complexity — two model providers in one workflow; No per-task goldiebench head-to-heads yet.
How does Goldie Bench score Muse Spark 1.2 vs Kilo Code?
Every demo on this page was built by Julian Goldie inside the Agent Operating System — same fixed prompt for both models, one shot, single HTML file out. Each result gets a 0–10 score on whether it ran, how close it hit the brief, and how good it looked. The highest score on each task gets gold; second gets silver; third gets bronze. See methodology for full provenance.
Related comparisons
Other head-to-heads using the same scoring system:
Muse Spark 1.2 vs Fusion Kilo Code vs Fusion Muse Spark 1.2 vs Claude Opus 5 Kilo Code vs Claude Opus 5 Muse Spark 1.2 vs Hermes MoA Kilo Code vs Hermes MoA Muse Spark 1.2 vs GPT-5.6 Sol Kilo Code vs GPT-5.6 SolFull model pages: Muse Spark 1.2 · Kilo Code · back to the leaderboard
The same stack Julian uses
Run this stack yourself.
Every demo on this bench was built inside the Agent Operating System — one prompt, one shot, single HTML file out. The Agent OS, the prompts, the templates, the weekly walkthroughs and 4,000+ founders shipping with it every day all live inside the AI Profit Boardroom.
4,000+founders
258documented wins
38countries
$59/momonthly






















