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Giosue Milan
Giosue Milan

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Why you are using the Gemini API wrong (and how to fix it)

If you are just throwing raw strings at the Gemini API and hoping for the best, you are leaving 90% of its power on the table.

Most developers treat LLMs like a glorified search engine. But if you want to build a real AI SaaS, you need to structure your prompts like an API payload.

Stop using raw strings. Start using Structured Outputs.

Instead of asking the model to "Format the output as JSON", you need to use response_mime_type: "application/json".

This guarantees the output is always valid JSON, which means you don't have to write messy RegEx to parse the response before saving it to your database.

The System Prompt is your architecture.

Your system prompt shouldn't just be "You are a helpful assistant." It needs to define constraints, tone, and fallback behavior.
If the API fails to generate a response, how does your app handle it? If it hallucinates, how do you catch it?

🔥 Skip the trial and error.
I built a production-ready Next.js boilerplate that already handles Gemini API rate limits, structured JSON outputs, and edge cases. I also compiled the Top 100 System Prompts for software engineers.

I dropped the price to exactly $1 today.
👉 Grab the Boilerplate & Prompts Here

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