Hlp, no tools helps=(. 500 error. FileApi VS SystemInstructions config (Parts [ ]) is now broken? WHY=( today it falls with 500 error?

Gemini API
1

Hi, I am offering a fresh FILEAPI file to config-systemIsntructions Parts[ ] object..
as i did all the week long and it workd. but now it falls with 500 error every time i add a fileapi-typed part.

{“error”:{“code”:500,“message”:“Internal error encountered.”,“status”:“INTERNAL”}}
[19:42:26] Status: 500

const res = await ai.models.generateContent({
model: ‘gemini-3-flash-preview’,
contents: prompt,
config: {
systemInstruction: {
parts: [
{ text: ’ do begin youo answer with a current Timestamp’},
{ text:’ let your name be John. use it every time for i am testing systemInstructions interface of type Parts[ ] '},

{ fileData:{ fileUri: myValidWorkingFresh_FILEAPI_Uri, mimeType: ‘text/plain’ } }, // fails and works here - every time - when i do comment/uncomment it =( worked previously good, or AssistentAI had broken working version and exchanged it with smth i misseen.
]
}
}
});

2

it works good without { fileData :{} } part, but i need a big data of rules for working to be sent ,
and send quickly,reusably, ..etc, as it was previos all week long…

i cant efford yet paid APIKEy to use Explicit cache , and it has worked perfectly o FreeApi for some days.

or am i dooing something syntaxically wrong … =((

Please Help