Deprecate Langchain::LLM::AI21 class (#962)

Author: andreibondarev

.env.example

@@ -1,4 +1,3 @@
-AI21_API_KEY=
 ANTHROPIC_API_KEY=
 AZURE_API_KEY=
 AZURE_CHAT_URI=

CHANGELOG.md

@@ -15,6 +15,7 @@
 - [BUGFIX] [https://github.com/patterns-ai-core/langchainrb/pull/953] Handle nil response in OpenAI LLM streaming
 - [BREAKING] [https://github.com/patterns-ai-core/langchainrb/pull/956] Deprecate `Langchain::Vectorsearch::Epsilla` class
 - [BREAKING] [https://github.com/patterns-ai-core/langchainrb/pull/961] Deprecate `Langchain::LLM::LlamaCpp` class
+- [BREAKING] [https://github.com/patterns-ai-core/langchainrb/pull/962] Deprecate `Langchain::LLM::AI21` class
 
 ## [0.19.4] - 2025-02-17
 - [BREAKING] [https://github.com/patterns-ai-core/langchainrb/pull/894] Tools can now output image_urls, and all tool output must be wrapped by a tool_response() method

README.md

@@ -57,7 +57,6 @@ The `Langchain::LLM` module provides a unified interface for interacting with va
 
 ## Supported LLM Providers
 
-- AI21
 - Anthropic
 - AWS Bedrock
 - Azure OpenAI

lib/langchain/llm/ai21.rb

@@ -17,6 +17,8 @@ class AI21 < Base
     }.freeze
 
     def initialize(api_key:, default_options: {})
+      Langchain.logger.warn "DEPRECATED: `Langchain::LLM::AI21` is deprecated, and will be removed in the next major version. Please use another LLM provider."
+
       depends_on "ai21"
 
       @client = ::AI21::Client.new(api_key)

lib/langchain/llm/base.rb

@@ -7,7 +7,6 @@ class ApiError < StandardError; end
   #
   # Langchain.rb provides a common interface to interact with all supported LLMs:
   #
-  # - {Langchain::LLM::AI21}
   # - {Langchain::LLM::Anthropic}
   # - {Langchain::LLM::Azure}
   # - {Langchain::LLM::Cohere}