How to Ensure Controlled and Contextual Responses Using Foundation Models ?

Hi everyone,

I’m currently exploring the use of Foundation models on Apple platforms to build a chatbot-style assistant within an app. While the integration part is straightforward using the new FoundationModel APIs, I’m trying to figure out how to control the assistant’s responses more tightly — particularly:

Ensuring the assistant adheres to a specific tone, context, or domain (e.g. hospitality, healthcare, etc.)

Preventing hallucinations or unrelated outputs

Constraining responses based on app-specific rules, structured data, or recent interactions

I’ve experimented with prompt, systemMessage, and few-shot examples to steer outputs, but even with carefully generated prompts, the model occasionally produces incorrect or out-of-scope responses.

Additionally, when using multiple tools, I'm unsure how best to structure the setup so the model can select the correct pathway/tool and respond appropriately. Is there a recommended approach to guiding the model's decision-making when several tools or structured contexts are involved?

Looking forward to hearing your thoughts or being pointed toward related WWDC sessions, Apple docs, or sample projects.

How to Ensure Controlled and Contextual Responses Using Foundation Models ?
 
 
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