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Head to head · LLM inference · October 2026 research run

Muse Spark Open vs Router.com (Ramp Router)

Router.com (Ramp Router) scores 54.5 (C) on agent readiness against Muse Spark Open's 53.5 (D), and leads in 3 of 7 scored categories. Muse Spark Open leads on reliability and payments & pricing. Both do llm inference.

Best model APIs and inference for AI agents · All 466 models comparisons

Muse Spark OpenMeta · Model API D53.5/100#823 of 1218 Router.com (Ramp Router)Ramp · Model router C54.5/100#798 of 1218

Which one, for what

Muse Spark Open D

Best for A team with a four-GPU Blackwell node, or two to four Mac Studios, that wants a 1M-token multimodal coding and agent model on its own hardware with no prompts leaving it.

Ahead on

  • Reliability, 42 against 25
  • Payments & pricing, 50 against 40

Also in its favour

  • No key needed to call it

Watch for

The NVFP4 checkpoint (about 537 GB) serves on four B300 GPUs and the BF16 one (about 1.65 TB) on eight

Router.com (Ramp Router) C

Best for Teams in the US that want one key for OpenAI, Anthropic, xAI and open-weight models, with routing to cheaper tiers and per-request cost, and can switch off content recording.

Ahead on

  • Agent ergonomics, 77 against 69
  • Security & auth, 66 against 44
  • Transparency & trust, 67 against 54

Also in its favour

  • A hosted endpoint, with nothing to install

Watch for

Ramp-side content recording is on by default and keeps prompts, outputs and tool calls for one year

Score by category

CategoryWeight this runMuse Spark OpenRouter.com (Ramp Router)Edge
Reliability16%204225Muse Spark Open +17
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26158Muse Spark Open +3
Agent ergonomics13%16.26977Router.com (Ramp Router) +8
Security & auth14%17.54466Router.com (Ramp Router) +22
Payments & pricing10%12.55040Muse Spark Open +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86059Muse Spark Open +1
Transparency & trust7%8.85467Router.com (Ramp Router) +13
Negative events≤1500
TotalD 53.5/100C 54.5/100

Facts side by side

FactMuse Spark OpenRouter.com (Ramp Router)
KindModel APIModel router
VendorMetaRamp
Hosted endpointno (local only)https://api.router.com/v1
TransportsHTTPHTTP
AuthNoneAPI key
PricingFreePay per use
x402nono
LicenceMuse Model Licence (source-available weights, not an OSI licence), free of charge with an attribution notice, a separate agreement with Meta before Model as a Service by a licensee group above $20M gross revenue, and the Muse Spark Open Usage PolicyClosed service under the Router Terms of Service (last updated 31 August 2026). The Ramp CLI that configures coding agents for Router is MIT.
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-152026-10-27
Terms last updated
Privacy policy last updatedno document linked
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularitynone1.7k npm/wk

Verdicts

Muse Spark Open

Muse Spark Open runs on the owner's hardware in seven runtimes, with OpenAI-compatible servers in vLLM and SGLang, standard tool calls, a 1M-token context and Meta's own serving docs. Serving the 537 GB NVFP4 checkpoint takes four B300 GPUs, Meta's download is gated by manual review, and the licence adds attribution and a revenue threshold for model resellers.

Router.com (Ramp Router)

Detailed Markdown docs with typed error codes, per-model capability data and routing an agent can set per request. No OpenAPI document, status page, changelog or published rate limits were found. Signup needs a US business email in a browser, and Ramp records prompts and outputs for a year by default unless switched off.

Before you call either

Muse Spark Open

  1. Start vLLM or SGLang with --reasoning-parser muse --tool-call-parser muse (vLLM also --enable-auto-tool-choice), or tool calls come back as raw text
  2. Set reasoning_effort to low or medium for short tasks. The default is xhigh, reasoning can't be turned off, and other values return an error
  3. Stop only on <|eot|> and end of text. Stopping on <|eom|> cuts off tool calls and final answers
  4. Stream long generations and leave max_tokens room for reasoning, or content can come back empty with finish_reason length
  5. Don't call Meta Model API for this model. Use a self-hosted server or a hosted provider's model string, such as meta-models/muse-spark-open

Router.com (Ramp Router)

  1. Switch off content recording in Settings before sending private data. It is on by default and keeps prompts and outputs for a year
  2. Read model ids from GET /v1/models at runtime. Ids are account-specific, an unknown one is a 404, and Gemini ids need your own Google key
  3. Use POST /v1/responses with a models list for fallbacks. Router stops falling back once a stream has started
  4. Set fallback_timeout and provider_timeout, or allow_flex_tier: false, when latency matters. Flex routing is on by default
  5. Treat both 401 invalid_api_key and 401 api_key_deactivated as a possibly locked key, and stop retrying on 402

Questions

Which is better for AI agents, Muse Spark Open or Router.com (Ramp Router)?

Router.com (Ramp Router) scores 54.5 (C) on agent readiness against Muse Spark Open's 53.5 (D), and leads in 3 of 7 scored categories. Muse Spark Open leads on reliability and payments & pricing.

Do Muse Spark Open and Router.com (Ramp Router) need an API key?

Muse Spark Open needs no key. Router.com (Ramp Router) needs an API key.

Can an agent call Muse Spark Open and Router.com (Ramp Router) without installing anything?

No hosted endpoint is listed for Muse Spark Open. Router.com (Ramp Router) has a hosted endpoint at https://api.router.com/v1.

Other comparisons with Muse Spark Open or Router.com (Ramp Router)

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