Head to head · Decision models · October 2026 research run

pplx-decider vs ScaleDown

pplx-decider scores 62.9 (B) on agent readiness against ScaleDown's 48.6 (D), and leads in 4 of 7 scored categories. ScaleDown leads on payments & pricing. Both do decision models.

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Which one, for what

pplx-decider B

Best for High-volume classification, routing and rubric scoring over text and images where a team wants a low hosted price and the option to run the same weights itself.

Ahead on

  • Reliability, 61 against 20
  • Schema & documentation, 90 against 69
  • Security & auth, 61 against 48
  • Maintenance & community, 62 against 56

Watch for

The Decisions API was released in October 2026, so its incident record is days long, and Perplexity's FAQ says it gives no uptime guarantee

ScaleDown D

Best for Cheap, high-volume labelling, routing and yes or no checks where a probability is more useful than prose, and for pulling described fields with offsets from text, images or PDFs.

Ahead on

  • Payments & pricing, 40 against 25

Also in its favour

  • Free to start without a card

Watch for

No status page, no published rate limits and no SLA outside enterprise contracts

Score by category

CategoryWeight this runpplx-deciderScaleDownEdge
Reliability16%206120pplx-decider +41
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.29069pplx-decider +21
Agent ergonomics13%16.27676even
Security & auth14%17.56148pplx-decider +13
Payments & pricing10%12.52540ScaleDown +15
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86256pplx-decider +6
Transparency & trust7%8.85254ScaleDown +2
Negative events≤150-2
TotalB 62.9/100D 48.6/100

Facts side by side

Factpplx-deciderScaleDown
KindModel APIModel API
VendorPerplexityCarbon ScaleDown, Inc.
Hosted endpointhttps://api.perplexity.ai/v1/decisionshttps://api.scaledown.xyz
TransportsHTTPHTTP
AuthAPI keyAPI key
PricingPay per usePay per use
Price for decision modelsfreenot published
x402nono
LicenceApache-2.0 for the published weights. The hosted Decisions API is a proprietary serviceProprietary hosted models under ScaleDown's Terms of Service. The langchain-scaledown integration is MIT
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-052026-10-14
Terms last updatedcouldn't be readcouldn't be read
Privacy policy last updatedcouldn't be readcouldn't be read
Customer content may train modelscouldn't be readcouldn't be read
Terms restrict automated accesscouldn't be readcouldn't be read
Terms restrict benchmarkingcouldn't be readcouldn't be read
Terms or service can change without noticecouldn't be readcouldn't be read
Arbitration or class-action waivercouldn't be readcouldn't be read
Popularitynone0 stars

Verdicts

pplx-decider

The hosted Decisions API has an OpenAPI description, typed questions, documented limits and a published price of $0.02 per million input tokens, and the v1.1 weights are public under Apache-2.0. The API is days old, the official Python SDK has no method for it, and the governing terms and privacy notice could not be read on 9 October 2026.

ScaleDown

Classify answers Jev-shaped choice, noul and score questions with probabilities, and Extract returns values with confidences and character offsets, at $0.05 per million input tokens with output free. There is no status page, no published rate limit and no public changelog, and the site's compliance claims contradict each other.

Before you call either

pplx-decider

  1. Send Authorization: Bearer. A key in x-api-key returns 401 on this endpoint.
  2. Set model on every request. A missing or unknown model returns 400, and the guide shows a -latest name rejected.
  3. Resize images to 2,048 tiles of 32 by 32 pixels or fewer before sending. Larger images end in a 504 after about a minute.
  4. Check the HTTP status before parsing an error. 404 and 405 have empty bodies, 504 can be HTML, and error.code changes type.
  5. For the weights, use the repository's autojev code. The card says default causal inference does not reproduce the evaluated setup.

ScaleDown

  1. Send several questions about one item in one /v1/scaledown call. Each becomes its own Classify call and the usage is summed
  2. Pin classify-1, extract-1 or summarize-1 once you've tuned thresholds on your own labelled cases
  3. Set context_chars to 0 and use top_n on Extract unless you need the 500 characters of context each side
  4. Set reasoning: false on /classify when you only need the label. The reasoning call bills its input at 2x
  5. Back off and retry on 429, 502 and 504. No limits are published and calls have no side effects

Questions

Which is better for AI agents, pplx-decider or ScaleDown?

pplx-decider scores 62.9 (B) on agent readiness against ScaleDown's 48.6 (D), and leads in 4 of 7 scored categories. ScaleDown leads on payments & pricing.

Do pplx-decider and ScaleDown need an API key?

Both need an API key.

Can an agent call pplx-decider and ScaleDown without installing anything?

Yes. pplx-decider has a hosted endpoint at https://api.perplexity.ai/v1/decisions and ScaleDown at https://api.scaledown.xyz.

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