C

Referencing a Pre-Uploaded File by file_id in an AI Request

See more AI Examples

Some AI proviers have a Files API that lets you upload content once and then reference it later in generation requests using a file_id. This is especially useful for large documents, reuse across multiple prompts, or keeping inputs structured and separate from your prompt text.

This example demonstrates how to use a file_id in a request.

C

#include <C_CkAi.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkAi ai;
    const char *file_id;
    HCkStringBuilder sbResponse;

    success = FALSE;

    success = FALSE;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    ai = CkAi_Create();

    // The provider can be "openai", "google", "claude", "mistral", "deepseek", "xai", or any provider
    // that supports referencing pre-uploaded files by a file_id (or file uri).
    CkAi_putProvider(ai,"openai");

    // Use your provider's API key.
    CkAi_putApiKey(ai,"MY_API_KEY");

    // Choose a model.
    CkAi_putModel(ai,"gpt-5-mini");

    // See the following example showing how to upload a file
    // Upload a File to an AI Provider (OpenAI, Google, Antropic, X)

    // Use the file_id of the pre-uploaded file.
    file_id = "file-5G2xncrEiHbVfYPRpFgP9c";
    CkAi_InputAddFileId(ai,file_id,"application/json");

    CkAi_InputAddText(ai,"Explain why Hamlet delays taking revenge, using only evidence from the file.");

    // Ask the AI for text output.
    success = CkAi_Ask(ai,"text");
    if (success == FALSE) {
        printf("%s\n",CkAi_lastErrorText(ai));
        CkAi_Dispose(ai);
        return;
    }

    // Get the text response.
    sbResponse = CkStringBuilder_Create();
    CkAi_GetOutputTextSb(ai,sbResponse);
    printf("%s\n",CkStringBuilder_getAsString(sbResponse));


    CkAi_Dispose(ai);
    CkStringBuilder_Dispose(sbResponse);

    }