Providers and Models

A provider is an AI service (OpenAI, Anthropic, Google, etc.). A model is a specific model offered by that provider (gpt-4o, claude-sonnet-4-20250514, gemini-2.0-flash).

GoAI uses a factory pattern: each provider package exports a Chat() function that returns a model implementing the provider.LanguageModel interface.

import "github.com/zendev-sh/goai/provider/openai"

model := openai.Chat("gpt-4o")

The model is then passed to GoAI functions like StreamText or GenerateText:

result, err := goai.GenerateText(ctx, model,
    goai.WithPrompt("Explain quantum computing in one sentence."),
)

Model Interfaces

GoAI defines three model interfaces in the provider package.

LanguageModel

Text generation and tool calling.

type LanguageModel interface {
    ModelID() string
    DoGenerate(ctx context.Context, params GenerateParams) (*GenerateResult, error)
    DoStream(ctx context.Context, params GenerateParams) (*StreamResult, error)
    Capabilities() ModelCapabilities
}

Used with GenerateText, StreamText, GenerateObject, and StreamObject.

EmbeddingModel

Vector embeddings from text.

type EmbeddingModel interface {
    ModelID() string
    DoEmbed(ctx context.Context, values []string, params EmbedParams) (*EmbedResult, error)
    MaxValuesPerCall() int
}

Used with Embed and EmbedMany.

ImageModel

Image generation from text prompts.

type ImageModel interface {
    ModelID() string
    DoGenerate(ctx context.Context, params ImageParams) (*ImageResult, error)
}

Used with GenerateImage.

Capabilities

Every LanguageModel exposes a Capabilities() method that describes what the model supports:

caps := model.Capabilities()
if caps.ToolCall {
    // safe to pass tools
}
if caps.Reasoning {
    // model supports extended thinking
}

The ModelCapabilities struct includes:

Field	Type	Description
Temperature	bool	Accepts temperature parameter
Reasoning	bool	Extended thinking / chain-of-thought
Attachment	bool	File attachment support
ToolCall	bool	Tool / function calling
InputModalities	ModalitySet	Supported input types (text, image, etc.)
OutputModalities	ModalitySet	Supported output types

Provider Configuration

Every provider accepts options for authentication and customization:

// Explicit API key
model := openai.Chat("gpt-4o", openai.WithAPIKey("sk-..."))

// Dynamic token source (OAuth, service accounts)
model := openai.Chat("gpt-4o", openai.WithTokenSource(myTokenSource))

// Custom HTTP client (proxies, logging, URL rewrite)
model := openai.Chat("gpt-4o", openai.WithHTTPClient(myClient))

If no API key or token source is provided, providers read from environment variables (e.g., OPENAI_API_KEY, ANTHROPIC_API_KEY).

Provider List

Provider	Import Path	Factory Functions
OpenAI	github.com/zendev-sh/goai/provider/openai	Chat, Embedding, Image
Anthropic	github.com/zendev-sh/goai/provider/anthropic	Chat
Google	github.com/zendev-sh/goai/provider/google	Chat, Embedding, Image
Azure	github.com/zendev-sh/goai/provider/azure	Chat, Image
Vertex AI	github.com/zendev-sh/goai/provider/vertex	Chat, Embedding, Image
Bedrock	github.com/zendev-sh/goai/provider/bedrock	Chat
Mistral	github.com/zendev-sh/goai/provider/mistral	Chat
xAI	github.com/zendev-sh/goai/provider/xai	Chat
Groq	github.com/zendev-sh/goai/provider/groq	Chat
DeepInfra	github.com/zendev-sh/goai/provider/deepinfra	Chat
OpenRouter	github.com/zendev-sh/goai/provider/openrouter	Chat
DeepSeek	github.com/zendev-sh/goai/provider/deepseek	Chat
Fireworks	github.com/zendev-sh/goai/provider/fireworks	Chat
Together	github.com/zendev-sh/goai/provider/together	Chat
Cohere	github.com/zendev-sh/goai/provider/cohere	Chat, Embedding
Cerebras	github.com/zendev-sh/goai/provider/cerebras	Chat
Perplexity	github.com/zendev-sh/goai/provider/perplexity	Chat
Ollama	github.com/zendev-sh/goai/provider/ollama	Chat, Embedding
vLLM	github.com/zendev-sh/goai/provider/vllm	Chat, Embedding
Compat	github.com/zendev-sh/goai/provider/compat	Chat, Embedding

The compat provider works with any OpenAI-compatible API. Pass a custom base URL:

import "github.com/zendev-sh/goai/provider/compat"

model := compat.Chat("my-model",
    compat.WithBaseURL("https://my-api.example.com/v1"),
    compat.WithAPIKey("my-key"),
)