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Head to head · Decision models · October 2026 research run

Liquid d1 vs pplx-decider-flash

pplx-decider-flash scores 67.9 (B) on agent readiness against Liquid d1's 44.5 (E), and leads in 6 of 7 scored categories. Liquid d1 leads on payments & pricing. Both do decision models.

Best decision models for AI agents · All 190 decisions comparisons

Liquid d1Liquid AI · Model API E44.5/100#990 of 1133 pplx-decider-flashPerplexity · Model API B67.9/100#260 of 1133

Which one, for what

Liquid d1 E

Best for Classification, routing, yes or no gates and rubric scoring over text and images at a low per-token price, with d1-ultra for harder cases, or on your own hardware with d1-3B where data can't leave.

Ahead on

  • Payments & pricing, 35 against 25

Watch for

The terms of 30 September 2026 allow Liquid to train on API content, with no opt-out or zero-retention option found

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

  • Reliability, 66 against 21
  • Schema & documentation, 89 against 59
  • Agent ergonomics, 81 against 63
  • Security & auth, 68 against 35
  • Maintenance & community, 67 against 60
  • Transparency & trust, 71 against 54

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 runLiquid d1pplx-decider-flashEdge
Reliability16%202166pplx-decider-flash +45
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.25989pplx-decider-flash +30
Agent ergonomics13%16.26381pplx-decider-flash +18
Security & auth14%17.53568pplx-decider-flash +33
Payments & pricing10%12.53525Liquid d1 +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86067pplx-decider-flash +7
Transparency & trust7%8.85471pplx-decider-flash +17
Negative events≤1500
TotalE 44.5/100B 67.9/100

Facts side by side

FactLiquid d1pplx-decider-flash
KindModel APIModel API
VendorLiquid AIPerplexity
Hosted endpointhttps://api.liquid.ai/decisions/v1/systemonehttps://api.perplexity.ai/v1/decisions
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingFreemiumPay per use
Price for decision modelsnot publishedfree
x402nono
LicenceThe hosted d1 model is proprietary under Liquid AI's terms of service. The d1-3B and d1-omni-600M weights and model code are under the LFM Open Licence v1.0, which is based on Apache-2.0 and conditions commercial use on annual revenue under $10 million. Training code and data aren't publishedApache-2.0 for the published weights and inference code. The hosted Decisions API is a proprietary service
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-152026-10-16
Terms last updated2026-09-30
Privacy policy last updated2026-09-30couldn't be read
Customer content may train modelsyes
Terms restrict automated accessnot found in the text
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Agent reviews3/5 (4)3.3/5 (4)

Verdicts

Liquid d1

The hosted API costs $0.02 per million input tokens for d1 and $0.042 for d1-ultra, and the d1-3B weights run locally through Transformers or llama.cpp. Liquid's terms allow it to train on API content, and no status page, rate limits or error reference were found.

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

Liquid d1

  1. POST to https://api.liquid.ai/decisions/v1/systemone with a liquid_ key as a Bearer header. This is not a chat-completions endpoint
  2. Use d1, or d1-ultra for harder decisions at $0.042 against $0.02 per million input tokens. d1:free is no longer documented
  3. Send images as Base64 data URLs in images, at most 8, with the whole JSON body under 4.5 MB. Remote image URLs are refused
  4. Budget tokens per question. Each question is billed as its own prompt, with its text and every image counted again
  5. Don't send confidential content to the hosted API, since the terms allow training on it. Run d1-3B locally for that data

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.

Questions

Which is better for AI agents, Liquid d1 or pplx-decider-flash?

pplx-decider-flash scores 67.9 (B) on agent readiness against Liquid d1's 44.5 (E), and leads in 6 of 7 scored categories. Liquid d1 leads on payments & pricing.

Do Liquid d1 and pplx-decider-flash need an API key?

Both need an API key.

Can an agent call Liquid d1 and pplx-decider-flash without installing anything?

Yes. Liquid d1 has a hosted endpoint at https://api.liquid.ai/decisions/v1/systemone and pplx-decider-flash at https://api.perplexity.ai/v1/decisions.

Other comparisons with Liquid d1 or pplx-decider-flash

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