python-web-tunnel

Use cloudflared with the command 'cloudflared tunnel --url http://localhost:PORT' to create a public URL without an account. It handles long-running requests over 30 seconds, unlike serveo.net or localtunnel which drop them.

cloudflared is the best choice because it handles requests lasting 30-120 seconds, which AI API calls often require. serveo.net drops long POSTs and localtunnel returns 503 errors under sustained load.

Probe each available model with a test request and cache the results, then show users a dropdown marking models as available, quota exhausted, or error. Set up a fallback chain such as gemini-3.5-flash to gemini-2.5-flash-lite.

Gemini truncates JSON mid-string when max_output_tokens is reached, even with response_mime_type set to JSON. Fix it by parsing character-by-character to find the last complete object, then auto-closing unclosed brackets.

Yes, use the Gemini File API: upload the file with client.files.upload, poll until its state leaves PROCESSING, then reference the returned URI via Part.from_uri in generate_content. Set Flask MAX_CONTENT_LENGTH for large uploads.

The constant referenced in app.config must be defined before app = Flask(__name__) executes. Python raises NameError when a variable is referenced before assignment, so define MAX_UPLOAD_MB at the top of the file.