llm/oai: add Mistral Medium 3 to oai models
diff --git a/llm/oai/oai.go b/llm/oai/oai.go
index 5518806..fe395e6 100644
--- a/llm/oai/oai.go
+++ b/llm/oai/oai.go
@@ -23,12 +23,14 @@
 	LlamaCPPURL  = "http://localhost:8080/v1"
 	TogetherURL  = "https://api.together.xyz/v1"
 	GeminiURL    = "https://generativelanguage.googleapis.com/v1beta/openai/"
+	MistralURL   = "https://api.mistral.ai/v1"
 
 	// Environment variable names for API keys
 	OpenAIAPIKeyEnv    = "OPENAI_API_KEY"
 	FireworksAPIKeyEnv = "FIREWORKS_API_KEY"
 	TogetherAPIKeyEnv  = "TOGETHER_API_KEY"
 	GeminiAPIKeyEnv    = "GEMINI_API_KEY"
+	MistralAPIKeyEnv   = "MISTRAL_API_KEY"
 )
 
 type Model struct {
@@ -134,6 +136,14 @@
 		Cost:      ModelCost{Input: 90, Output: 90}, // not entirely sure about this, they don't list pricing anywhere convenient
 		APIKeyEnv: FireworksAPIKeyEnv,
 	}
+
+	MistralMedium = Model{
+		UserName:  "mistral-medium-3",
+		ModelName: "mistral-medium-latest",
+		URL:       MistralURL,
+		Cost:      ModelCost{Input: 40, Output: 200},
+		APIKeyEnv: MistralAPIKeyEnv,
+	}
 )
 
 // Service provides chat completions.