Perplexity

The perplexity driver connects Polyglot Decision to Perplexity's hosted Decisions API (POST https://api.perplexity.ai/v1/decisions). It speaks the System One protocol: a state plus a map of typed noul, choice, and score questions in, one probability distribution per question out.

Model	Input limit	Input price
`pplx-decider-v1-27b`	under 262,144 tokens	$0.04 per M tokens

Output tokens are free.

Configure the driver¶

Set a Perplexity API key:

PERPLEXITY_API_KEY=your-key
// @doctest id="283c"

Then select the bundled preset:

use Cognesy\Polyglot\Decision\Decision;

$decision = Decision::using('perplexity');
// @doctest id="300b"

The preset targets https://api.perplexity.ai/v1/decisions with pplx-decider-v1-27b, the only model the API serves.

Protocol notes¶

A Noul question needs instructions, criteria, or both. The driver rejects a Noul with neither before sending. Choice and Score questions may omit instructions.
Perplexity accepts 1 to 128 questions per request, 1 to 255 Choice options, and up to 10 Score levels. Text, object, and list state keep their System One shape.
The x-request-id response header becomes the provider request ID.
Probabilities sum to about 1; the adapter checks sums and probability-weighted scores with a 0.01 tolerance. Identical requests can differ in the second decimal place, so set thresholds with some margin.
Image parts in state are not exposed by the Decision API.

HTTP 401 and 403 map to authentication errors, 429 to rate limits (with Retry-After), 408 and 5xx (including the roughly one-minute 504 timeout) to retriable transient errors, and other 4xx responses such as 400 and 413 to invalid requests. A non-JSON body, such as an HTML gateway page, fails closed.

Live smoke¶

POLYGLOT_PERPLEXITY_LIVE=1 vendor/bin/pest packages/polyglot/tests/Integration/PerplexityLiveTest.php
# @doctest id="ef11"

The test runs one mixed Noul, Choice, and Score decision through the bundled preset and needs PERPLEXITY_API_KEY in the environment or the repository .env.