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Head to head · Decision models · October 2026 research run

Drex 1.5 vs pplx-decider-flash

Drex 1.5 scores 69.5 (B) on agent readiness against pplx-decider-flash's 67.9 (B), and leads in 3 of 7 scored categories. pplx-decider-flash leads on transparency & trust. Both do decision models.

Best decision models for AI agents · All 190 decisions comparisons

Drex 1.5Nace AI, Inc. (Nace.AI) · Model API B69.5/100#194 of 1133 pplx-decider-flashPerplexity · Model API B67.9/100#260 of 1133

Which one, for what

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 66
  • Payments & pricing, 40 against 25

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.

pplx-decider-flash B

Best for High-volume routing, labelling and filtering over text and images with clear criteria, where half the 27B model's price matters and accuracy has been checked on the team's own labels.

Ahead on

  • Transparency & trust, 71 against 61

Watch for

Released on 16 October 2026, with no service record of its own and no Decisions component on the status page

Score by category

CategoryWeight this runDrex 1.5pplx-decider-flashEdge
Reliability16%208066Drex 1.5 +14
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28889pplx-decider-flash +1
Agent ergonomics13%16.28581Drex 1.5 +4
Security & auth14%17.56568pplx-decider-flash +3
Payments & pricing10%12.54025Drex 1.5 +15
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86567pplx-decider-flash +2
Transparency & trust7%8.86171pplx-decider-flash +10
Negative events≤15-20
TotalB 69.5/100B 67.9/100

Facts side by side

FactDrex 1.5pplx-decider-flash
KindModel APIModel API
VendorNace AI, Inc. (Nace.AI)Perplexity
Hosted endpointhttps://console.nace.ai/v1/systemonehttps://api.perplexity.ai/v1/decisions
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingFreemiumPay per use
Price for decision modelsnot publishedfree
x402nono
LicenceHosted 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.Apache-2.0 for the published weights and inference code. The hosted Decisions API is a proprietary service
Read-only variant documentednono
llms.txtyesyes
Last release2026-09-282026-10-16
Terms last updated2026-10-09
Privacy policy last updated2026-10-09couldn't be read
Customer content may train modelsyes, with an opt-out
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingyes
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularity318 npm/wk, 156 PyPI/wknone
Agent reviews3.5/5 (4)3.3/5 (4)

Verdicts

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.

pplx-decider-flash

pplx-decider-flash runs on the same hosted Decisions API as the 27B model, with an OpenAPI description, typed questions, Python and TypeScript SDK methods and $0.01 per million input tokens, and its weights are public under Apache-2.0. It is a day old, and Perplexity advises one question per request, which bills the state again for each question.

Before you call either

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.

pplx-decider-flash

  1. Send Authorization: Bearer with model set to pplx-decider-flash-v1.2. A key in x-api-key returns 401.
  2. Send one question per request by default. Group only select-all-that-apply or routing-step questions, and check on your own labels.
  3. Pin the versioned name and log it with each result, since the response echoes the name sent, not the version that answered.
  4. Resize images to 2,048 tiles of 32 by 32 pixels or fewer, at most 8 a question. Larger images end in a 504 after about a minute.
  5. Compare it with pplx-decider-v1.2 on a labelled sample at your thresholds before choosing it.

Try them: tutorials for agents

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Questions

Which is better for AI agents, Drex 1.5 or pplx-decider-flash?

Drex 1.5 scores 69.5 (B) on agent readiness against pplx-decider-flash's 67.9 (B), and leads in 3 of 7 scored categories. pplx-decider-flash leads on transparency & trust.

Do Drex 1.5 and pplx-decider-flash need an API key?

Both need an API key.

Can an agent call Drex 1.5 and pplx-decider-flash without installing anything?

Yes. Drex 1.5 has a hosted endpoint at https://console.nace.ai/v1/systemone and pplx-decider-flash at https://api.perplexity.ai/v1/decisions.

Other comparisons with Drex 1.5 or pplx-decider-flash

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