o ÿièã@sTdZddlZddlmZddlmZddlmZmZddl m Z Gdd„deƒZ dS) uûPerplexity LLM adapter for Pipecat. Perplexity's API uses an OpenAI-compatible interface but enforces stricter constraints on conversation history structure: 1. **Strict role alternation** — Messages must alternate between "user"/"tool" and "assistant" roles. Consecutive messages with the same role (e.g. two "user" messages in a row) are rejected with: ``"messages must be an alternating sequence of user/tool and assistant messages"`` 2. **No non-initial system messages** — "system" messages are only allowed at the start of the conversation. A system message after a non-system message causes: ``"only the initial message can have the system role"`` 3. **Last message must be user/tool** — The final message in the conversation must have role "user" or "tool". A trailing "assistant" message causes: ``"the last message must have the user or tool role"`` This adapter transforms the message list to satisfy all three constraints before the messages are sent to Perplexity's API. éN)ÚList)ÚChatCompletionMessageParam)ÚOpenAILLMAdapterÚOpenAILLMInvocationParams)Ú LLMContextcsDeZdZdZdedef‡fdd„ Zdeedeefdd„Z ‡Z S) ÚPerplexityLLMAdapteraRAdapter that transforms messages to satisfy Perplexity's API constraints. Perplexity's API is stricter than OpenAI about message structure. This adapter extends ``OpenAILLMAdapter`` and applies message transformations to ensure compliance with Perplexity's constraints (role alternation, no non-initial system messages, last message must be user/tool). The transformations are applied in ``get_llm_invocation_params`` after the parent adapter extracts messages from the LLM context, and before ``build_chat_completion_params`` prepends ``system_instruction``. ÚcontextÚreturncs&tƒ |¡}| t|dƒ¡|d<|S)aWGet OpenAI-compatible invocation parameters with Perplexity message fixes applied. Args: context: The LLM context containing messages, tools, etc. Returns: Dictionary of parameters for Perplexity's ChatCompletion API, with messages transformed to satisfy Perplexity's constraints. Úmessages)ÚsuperÚget_llm_invocation_paramsÚ_transform_messagesÚlist)ÚselfrÚparams©Ú __class__©ú`/home/ubuntu/.local/lib/python3.10/site-packages/pipecat/adapters/services/perplexity_adapter.pyr 4s z.PerplexityLLMAdapter.get_llm_invocation_paramsr cCsŒ|s|St |¡}d}tt|ƒƒD]}|| d¡dkr%|s$d||d<qd}qd}|t|ƒdkrª||}||d}|d|dkrJdkrQnn|d7}nQ|d|dkržt| d¡tƒrkd |dd œg|d<t| d¡tƒr}d |dd œg|d<t| d¡tƒr–t| d¡tƒr–|d |d¡|  |d¡n|d7}|t|ƒdks2|rÄ|d  d¡d krÄ|  ¡|rÄ|d  d¡d ksµ|S) uêTransform messages to satisfy Perplexity's API constraints. Applies three transformation steps in order: 1. **Convert non-initial system messages to user** — Any system message after the initial system message block is converted to role "user", since Perplexity rejects system messages after a non-system message. 2. **Merge consecutive same-role messages** — After the above conversions, adjacent messages with the same role are merged using list-of-dicts content format. This ensures strict role alternation (e.g. a converted system→user message adjacent to an existing user message gets merged). 3. **Remove trailing assistant messages** — If the last message is "assistant", remove it. OpenAI appears to silently ignore trailing assistant messages server-side, so removing them preserves equivalent behavior while satisfying Perplexity's "last message must be user/tool" constraint. Note: we intentionally do *not* convert a trailing system message to "user". That would make the transformation unstable across calls — Perplexity appears to have statefulness/caching within a conversation, so a message that was sent as "user" in one call but becomes "system" in the next (once more messages are appended) causes errors. If the context consists entirely of system messages, the Perplexity API call will fail, but that mistake will be caught right away. Args: messages: List of message dicts with "role" and "content" keys. Returns: Transformed list of message dicts satisfying Perplexity's constraints. TÚroleÚsystemÚuserFréÚcontentÚtext)ÚtyperéÿÿÿÿÚ assistant) ÚcopyÚdeepcopyÚrangeÚlenÚgetÚ isinstanceÚstrrÚextendÚpop)rr Úin_initial_system_blockÚiÚcurrentÚnext_msgrrrr Bs@%  €    ÿíÿz(PerplexityLLMAdapter._transform_messages) Ú__name__Ú __module__Ú __qualname__Ú__doc__rrr rrr Ú __classcell__rrrrr's ÿþr) r.rÚtypingrÚopenai.types.chatrÚ)pipecat.adapters.services.open_ai_adapterrrÚ*pipecat.processors.aggregators.llm_contextrrrrrrÚs