Cannot use JSON files in generateContent method

[PaulSinghDev]

Environment details

• Programming language: Typescript
• OS: MacOS
• Package version: 1.10.0

Steps to reproduce

1. upload a JSON file from an in memory JSON object
2. Try and use it

example:

import dotenv from "dotenv";
dotenv.config();

import { createPartFromUri, GoogleGenAI } from "@google/genai";

const gemini = new GoogleGenAI({ apiKey: process.env.GEMINI_API_KEY });

export async function main() {
  let someJson = await gemini.files.upload({
    file: new Blob([Buffer.from(JSON.stringify({ hey: "yo" }))]),
    config: {
      mimeType: "application/json",
    },
  });

  let filesProcessed = false;
  while (!filesProcessed) {
    if (someJson.state === "PROCESSING") {
      console.log(`[INFO] Files processing, waiting 2s`);

      await new Promise((resolve) => {
        setTimeout(resolve, 2000);
      });
    } else {
      filesProcessed = true;
      someJson = await gemini.files.get({
        name: someJson.name as string,
      });
      console.log(`[INFO] Markdown file processed, state: ${someJson.state}`);
    }
  }
  const response = await gemini.models.generateContent({
    model: "gemini-2.5-flash",
    contents: [
      createPartFromUri(someJson.uri as string, someJson.mimeType as string),
      `I have provided you with a JSON, tell me something about it`,
    ],
  });

  console.log(response.text);
}

main()
  .then(() => process.exit(0))
  .catch((e) => {
    console.error(e);
    process.exit(1);
  });