LangChain Together

0.4.0 verified Fri May 01 auth: no python

An integration package connecting Together AI's API with LangChain. Provides chat models and embeddings. Current version 0.4.0, requires Python >=3.10, <4.0. Release cadence is irregular; latest releases include security patches and MCP server features.

pip install langchain-together

Common errors

error ModuleNotFoundError: No module named 'langchain_together' ↓

cause Package not installed or wrong import path (e.g., from langchain.llms import Together).

fix

Install with 'pip install langchain-together' and import as 'from langchain_together import ChatTogether'.

error InvalidRequestError: 'model' is not a valid parameter ↓

cause Passing the model name as a keyword argument 'model' when it should be passed as positional or via model_kwargs.

fix

Use the correct parameter name: ChatTogether(model='mistralai/Mixtral-8x7B-Instruct-v0.1') or ChatTogether(model_kwargs={'model': '...'}) – check the latest API.

error AuthenticationError: 401 Unauthorized ↓

cause API key missing or incorrect.

fix

Set the TOGETHER_API_KEY environment variable or pass the key via the 'together_api_key' parameter.

error TypeError: __init__() got an unexpected keyword argument 'together_api_key' ↓

cause Using an older version of langchain-together that expected the parameter name 'api_key' instead of 'together_api_key'.

fix

Upgrade to latest version: pip install --upgrade langchain-together

Warnings

breaking Version 0.2.0 introduced a new package structure. If you were using the old langchain_together from community, imports must be updated to 'from langchain_together import ...' instead of 'from langchain.llms import Together' ↓

fix Change imports to the new package: from langchain_together import ChatTogether

deprecated The 'model' parameter used to accept model IDs like 'togethercomputer/llama-2-70b-chat'. These legacy IDs are deprecated in favor of Together AI's new model format (e.g., 'mistralai/Mixtral-8x7B-Instruct-v0.1'). ↓

fix Use the new model naming convention as documented by Together AI.

gotcha The environment variable for the API key is 'TOGETHER_API_KEY', not 'TOGETHER_AI_KEY' or 'TOGETHER_AI_API_KEY'. ↓

fix Set the correct environment variable or pass directly via 'together_api_key' parameter.

gotcha ChatTogether does not support all models available via Together AI's API. Some models may require additional parameters like 'temperature' or 'max_tokens' which are not passed through by default. ↓

fix Check LangChain documentation for supported models and pass extra kwargs if needed.

Imports

ChatTogether

wrong

from langchain_together.chat import ChatTogether

correct

from langchain_together import ChatTogether

Incorrect: ChatTogether is exposed at the top-level package.

TogetherEmbeddings

wrong

from langchain_together.embeddings import TogetherEmbeddings

correct

from langchain_together import TogetherEmbeddings

Incorrect: embeddings are also at top-level.

Quickstart

Basic usage: instantiate ChatTogether with API key and model, then invoke.

import os
from langchain_together import ChatTogether

chat = ChatTogether(
    together_api_key=os.environ.get("TOGETHER_API_KEY", ""),
    model="mistralai/Mixtral-8x7B-Instruct-v0.1"
)

response = chat.invoke("Hello, how are you?")
print(response.content)