1 files changed, 49 insertions, 0 deletions
diff --git a/internal/llm/provider.go b/internal/llm/provider.go
new file mode 100644
index 0000000..fd9d4d3
--- /dev/null
+++ b/internal/llm/provider.go
@@ -0,0 +1,49 @@
+package llm
+
+import (
+	"context"
+	"errors"
+	"log"
+	"os"
+)
+
+// Message represents a chat-style prompt message.
+type Message struct {
+	Role    string
+	Content string
+}
+
+// Client is a minimal LLM provider interface.
+// Future providers (Ollama, etc.) should implement this.
+type Client interface {
+	// Chat sends chat messages and returns the assistant text.
+	Chat(ctx context.Context, messages []Message, opts ...RequestOption) (string, error)
+}
+
+// Options for a request. Providers may ignore unsupported fields.
+type Options struct {
+	Model       string
+	Temperature float64
+	MaxTokens   int
+	Stop        []string
+}
+
+// RequestOption mutates Options.
+type RequestOption func(*Options)
+
+func WithModel(model string) RequestOption    { return func(o *Options) { o.Model = model } }
+func WithTemperature(t float64) RequestOption { return func(o *Options) { o.Temperature = t } }
+func WithMaxTokens(n int) RequestOption       { return func(o *Options) { o.MaxTokens = n } }
+func WithStop(stop ...string) RequestOption {
+	return func(o *Options) { o.Stop = append([]string{}, stop...) }
+}
+
+// NewDefault returns the default provider using environment configuration.
+// Currently this is the OpenAI provider using OPENAI_API_KEY.
+func NewDefault(logger *log.Logger) (Client, error) {
+	apiKey := os.Getenv("OPENAI_API_KEY")
+	if apiKey == "" {
+		return nil, errors.New("OPENAI_API_KEY is not set")
+	}
+	return newOpenAIFromEnv(apiKey, logger), nil
+}