Head to head · Decision models · October 2026 research run

Celeris-1 Decision vs Drex 1.5

Drex 1.5 scores 69.7 (B) on agent readiness against Celeris-1 Decision's 49.3 (D), and leads in every scored category. Both do decision models.

Best decision models for AI agents · All 91 decisions comparisons

Which one, for what

Celeris-1 Decision D

Best for Multimodal classification, routing and bounded decisions with probabilities and optional explanations

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Early-access terms and capacity-dependent workspace activation

Drex 1.5 B

Best for Routing, triage and yes or no gates inside an agent, where the caller supplies the options and acts on the probabilities. Suited to hosted use at a low per-token price, or to open weights where the licence fits.

Ahead on

  • Reliability, 80 against 40
  • Schema & documentation, 88 against 60
  • Agent ergonomics, 85 against 80
  • Security & auth, 65 against 45
  • Payments & pricing, 40 against 20
  • Maintenance & community, 65 against 40
  • Transparency & trust, 63 against 53

Watch for

The rank 1 claim comes from Nace's own run on Decision Index 0.3.1, and Drex is not on the public board for 0.3 or 0.2.1.

Score by category

CategoryWeight this runCeleris-1 DecisionDrex 1.5Edge
Reliability16%204080Drex 1.5 +40
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26088Drex 1.5 +28
Agent ergonomics13%16.28085Drex 1.5 +5
Security & auth14%17.54565Drex 1.5 +20
Payments & pricing10%12.52040Drex 1.5 +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.84065Drex 1.5 +25
Transparency & trust7%8.85363Drex 1.5 +10
Negative events≤150-2
TotalD 49.3/100B 69.7/100

Facts side by side

FactCeleris-1 DecisionDrex 1.5
KindModel APIModel API
VendorCeleris (Marqo Inc)Nace AI, Inc. (Nace.AI)
Hosted endpointhttps://inference.celeris.ai/celeris-1-decision/v1/systemonehttps://console.nace.ai/v1/systemone
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingPay per useFreemium
Price for decision modelsfreenot published
x402nono
LicenceProprietary hosted model under Celeris terms of serviceHosted API under the Nace AI Terms of Service, last updated 5 May 2026. Weights under the Nace AI Open RAIL-M licence (modified, version 1.0, October 2026), which is not an open-source licence. Businesses above $1 million in revenue or funding need a separate commercial licence, and competing products are excluded. The bundled code/kev package, derived from Jared Palmer's Kev (https://github.com/jaredpalmer/kev), and the GitHub repository are Apache-2.0, and the agent skill is MIT.
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-082026-09-28
Terms last updated2026-09-08
Privacy policy last updated2026-07-23
Customer content may train modelsnot found in the text
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingyes
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Popularitynone318 npm/wk, 156 PyPI/wk

Verdicts

Celeris-1 Decision

Typed probabilities, image inputs and optional explanations suit routing and classification inside an agent. Both System One and OpenAI Decisions request formats are documented. The service remains early access under its terms, activation can queue, and prepaid credit expires after 30 days. The published accuracy and latency figures are Celeris measurements, not Anchor Terminal tests.

Drex 1.5

The hosted endpoint has a public OpenAPI document, published limits and pinned model versions, at $0.05 per million input tokens with no output charge. The #1 under 10B claim rests on Nace's own run, since Drex is absent from both public boards. Weights carry Open RAIL-M, which requires a commercial licence above $1 million in revenue or funding.

Before you call either

Celeris-1 Decision

  1. Use the decision model path and matching model field. This model has no chat, Responses or models endpoint.
  2. Use at most 512 questions per request, or 64 with explanations. Both endpoints reject streaming.
  3. Preserve x_celeris in a custom Jev SDK response model when reading explanations. The default response type drops it.
  4. Retry 429 with Retry-After and backoff. Stop on 402 until workspace credit is replenished.
  5. Read usage.input_tokens for cost, including images and request overhead. Track credit expiry separately from token consumption.

Drex 1.5

  1. Call https://console.nace.ai/v1/systemone with Authorization: Bearer nace_sk_..., and pin model drex-v1.5 rather than drex-latest in production.
  2. Stop on 402 insufficient_credit or 402 payment_required until credit is topped up or the unpaid invoice is paid.
  3. Retry 429 and 529 after retry-after-ms. On a 422 for an unknown model, use one of the ids the error message lists.
  4. Keep state below 131,072 tokens and the body below 1,048,576 bytes, and send at most 512 questions per request.
  5. Keep the key on a server. A key in browser code is exposed, and the /v1 routes send no Access-Control-Allow-Origin header.
  6. Check usage.input_tokens and the usage CSV after retries, since /v1/systemone documents no idempotency key.

Questions

Which is better for AI agents, Celeris-1 Decision or Drex 1.5?

Drex 1.5 scores 69.7 (B) on agent readiness against Celeris-1 Decision's 49.3 (D), and leads in every scored category.

Do Celeris-1 Decision and Drex 1.5 need an API key?

Both need an API key.

Can an agent call Celeris-1 Decision and Drex 1.5 without installing anything?

Yes. Celeris-1 Decision has a hosted endpoint at https://inference.celeris.ai/celeris-1-decision/v1/systemone and Drex 1.5 at https://console.nace.ai/v1/systemone.

Other comparisons with Celeris-1 Decision or Drex 1.5

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