Provider Abstraction Architecture

This document explains how AI functions, model specifications, and provider implementations connect in the AI SDK. It starts with an abstract high-level view and then details each V4 model type, including the AI functions that use it and small UML diagrams.

High-Level Architecture

• AI functions: user-facing language functions (for example, streamText)
• Model specification: LanguageModelV4
• Provider implementations: provider-specific language model implementations of LanguageModelV4

classDiagram
    class AIFunction
    class LanguageModelV4 {
      <<interface>>
    }
    class ProviderLanguageModelImplementationA
    class ProviderLanguageModelImplementationB

    AIFunction ..> LanguageModelV4 : uses
    ProviderLanguageModelImplementationA ..|> LanguageModelV4 : implements
    ProviderLanguageModelImplementationB ..|> LanguageModelV4 : implements

Model-Type Details

If you're unable to find any of the functions mentioned below in the codebase, they may only exist with an experimental_ prefix. This means they're experimental, and stable versions will likely be implemented at a later point.

Language Model (LanguageModelV4)

Language models are used for text generation and structured generation workflows from prompt or message input.

• AI functions
  • generateText - packages/ai/src/generate-text/generate-text.ts - Generates a complete text result from a language model in a single call.
  • streamText - packages/ai/src/generate-text/stream-text.ts - Streams language model output incrementally as it is produced.
• Model specification
  • LanguageModelV4 - packages/provider/src/language-model/v4/language-model-v4.ts
• Provider implementations (examples)
  • OpenAIChatLanguageModel, AnthropicMessagesLanguageModel

classDiagram
    class generateText
    class streamText
    class LanguageModelV4 {
      <<interface>>
    }
    class OpenAILanguageModel

    generateText ..> LanguageModelV4 : uses
    streamText ..> LanguageModelV4 : uses
    OpenAILanguageModel ..|> LanguageModelV4 : implements

Embedding Model (EmbeddingModelV4)

Embedding models are used to convert text into numeric vectors for similarity and retrieval use cases.

• AI functions
  • embed - packages/ai/src/embed/embed.ts - Creates a single embedding vector for one text value.
  • embedMany - packages/ai/src/embed/embed-many.ts - Creates embedding vectors for multiple text values, batching calls when needed.
• Model specification
  • EmbeddingModelV4 - packages/provider/src/embedding-model/v4/embedding-model-v4.ts
• Provider implementations (examples)
  • OpenAIEmbeddingModel, MistralEmbeddingModel

classDiagram
    class embed
    class embedMany
    class EmbeddingModelV4 {
      <<interface>>
    }
    class OpenAIEmbeddingModel

    embed ..> EmbeddingModelV4 : uses
    embedMany ..> EmbeddingModelV4 : uses
    OpenAIEmbeddingModel ..|> EmbeddingModelV4 : implements

Image Model (ImageModelV4)

Image models are used to generate image outputs from text prompts.

• AI functions
  • generateImage - packages/ai/src/generate-image/generate-image.ts - Generates one or more images from prompt input.
• Model specification
  • ImageModelV4 - packages/provider/src/image-model/v4/image-model-v4.ts
• Provider implementations (examples)
  • OpenAIImageModel, GoogleGenerativeAIImageModel

classDiagram
    class generateImage
    class ImageModelV4 {
      <<interface>>
    }
    class OpenAIImageModel

    generateImage ..> ImageModelV4 : uses
    OpenAIImageModel ..|> ImageModelV4 : implements

Reranking Model (RerankingModelV4)

Reranking models are used to reorder candidate documents by relevance to a query.

• AI functions
  • rerank - packages/ai/src/rerank/rerank.ts - Reorders documents and returns a relevance-ranked result set for a query.
• Model specification
  • RerankingModelV4 - packages/provider/src/reranking-model/v4/reranking-model-v4.ts
• Provider implementations (examples)
  • CohereRerankingModel, BedrockRerankingModel

classDiagram
    class rerank
    class RerankingModelV4 {
      <<interface>>
    }
    class CohereRerankingModel

    rerank ..> RerankingModelV4 : uses
    CohereRerankingModel ..|> RerankingModelV4 : implements

Transcription Model (TranscriptionModelV4)

Transcription models are used to convert audio input into text transcripts.

• AI functions
  • transcribe - packages/ai/src/transcribe/transcribe.ts - Transcribes audio into text with segment and metadata support.
• Model specification
  • TranscriptionModelV4 - packages/provider/src/transcription-model/v4/transcription-model-v4.ts
• Provider implementations (examples)
  • OpenAITranscriptionModel, DeepgramTranscriptionModel

classDiagram
    class transcribe
    class TranscriptionModelV4 {
      <<interface>>
    }
    class OpenAITranscriptionModel

    transcribe ..> TranscriptionModelV4 : uses
    OpenAITranscriptionModel ..|> TranscriptionModelV4 : implements

Speech Model (SpeechModelV4)

Speech models are used to synthesize audio from text input.

• AI functions
  • generateSpeech - packages/ai/src/generate-speech/generate-speech.ts - Generates speech audio from text input.
• Model specification
  • SpeechModelV4 - packages/provider/src/speech-model/v4/speech-model-v4.ts
• Provider implementations (examples)
  • OpenAISpeechModel, ElevenLabsSpeechModel

classDiagram
    class generateSpeech
    class SpeechModelV4 {
      <<interface>>
    }
    class OpenAISpeechModel

    generateSpeech ..> SpeechModelV4 : uses
    OpenAISpeechModel ..|> SpeechModelV4 : implements

Video Model (VideoModelV4)

Video models are used to generate video outputs from prompts.

• AI functions
  • generateVideo - packages/ai/src/generate-video/generate-video.ts - Generates one or more videos from prompt input.
• Model specification
  • VideoModelV4 - packages/provider/src/video-model/v4/video-model-v4.ts
• Provider implementations (examples)
  • FalVideoModel, ReplicateVideoModel

classDiagram
    class generateVideo
    class VideoModelV4 {
      <<interface>>
    }
    class FalVideoModel

    generateVideo ..> VideoModelV4 : uses
    FalVideoModel ..|> VideoModelV4 : implements