Thank you for your response. In tokenizer_config.json I have the line "tokenizer_class": "TokenizersBackend", In my Swift code I have let modelFactory = LLMModelFactory.shared let modelConfiguration = LLMRegistry.shared.configuration(id: "pharmpk/pk-mistral-7b-v0.3-4bit") // Load the model off the main actor, then assign on the main actor let loaded = try await modelFactory.loadContainer(configuration: modelConfiguration) { progress in print("Downloading progress: \(progress.fractionCompleted * 100)%") } await MainActor.run { self.model = loaded } It appears the difference between code that works and what doesn't is the format of the train/valid.json I'm providing to mlx_;m.lora Text type input seems to work {"text": "This is an example for the model."} I thought I might get a better model using the chat format {"messages":[{"role":"user","content":"What is pharmacokinetics?"},{"role":"assistant","content":"Pharmacokinetics is the study of the time course of drug absorption, distribution, metabolism, and excretion (ADME). It involves the mathematical analysis of these processes to describe and predict drug concentrations in the body over time. The term comes from the Greek words 'pharmakon' (drug) and 'kinesis' (movement), literally meaning the movement of drugs through the body."}]} This is when I get the error after loading the 'new-fused' model I don't know where to add the Manual setting of tokenizer type, in my Swift code? Thanks

Same code with MLX libraries 2.25.8 but new model I get the same error. Might need to revisit the new model

You can add your own model with MLX. I've used MLX_LM.lora to 'upgrade' Mistral-7B-Instruct-v0.3-4bit with my own content. The 'adapter' folder that is created can be added to the original model with mlx_lm.fuse and tested with mlx_lm.generate in the Terminal. I then added the resulting Models folder into my macOS/iOS Swift app. The app works on my Mac as expected. It worked on my iPhone a few days ago but now crashes in the simulator. I don't want to try it my phone until it works (again) on the simulator. The models folder contains the files created by the fuse command. I'm not sure that I changed anything in the last few days but it seems to be crashing in the loadmodel function with a lot of 'strange' output that I don't understand. My loadModel func `func loadModel() async throws -> Void { // return // one test for model not loaded alert // Avoid reloading if the model is already loaded let isLoaded = await MainActor.run { self.model != nil } if isLoaded { return } let modelFactory = LLMModelFactory.shared let configuration = MLXLMCommon.ModelConfiguration( directory: Bundle.main.resourceURL!, ) // Load the model off the main actor, then assign on the main actor let loaded = try await modelFactory.loadContainer(configuration: configuration) await MainActor.run { self.model = loaded } }` I plan to back track to previous commits to see where the problem might be. I may have used some ChatGPT help which isn't always helpful ;-)

The github explains the format fairly well. I've added info from my eBook content after saving the Pages version as plain text. I created the train.json file by breaking the text file into lines an added '{"text": "My text info"}' around each line My text info. I fudged the valid.json file by including a small part of the train.json. The biggest problem was finding special characters in my original that weren't json compatible (e.g. tab character). This was just for adding 'text' content to the model using LoRa.