From e4bf6281c6fb136cbed12dfdf7ca6f671caae718 Mon Sep 17 00:00:00 2001
From: Paul Kompfner <paul@daily.co>
Date: Thu, 12 Mar 2026 14:56:37 -0400
Subject: [PATCH] Add changelog for #4009

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+- Added `PerplexityLLMAdapter` that automatically transforms conversation messages to satisfy Perplexity's stricter API constraints (strict role alternation, no non-initial system messages, last message must be user/tool). Previously, certain conversation histories could cause Perplexity API errors that didn't occur with OpenAI (`PerplexityLLMService` subclasses `OpenAILLMService` since Perplexity uses an OpenAI-compatible API).