Gemini API

Gemini API Failed: Common Causes and Fixes

Use this checklist when AI character card generation fails, returns an empty result, switches to fallback output, or cannot parse the model response.

Do not paste your API key into public chats, screenshots, logs, or support posts. If a key was exposed, rotate it in the provider console before testing again.

Symptoms

  • Basic connection works, but full character card generation fails.
  • The app reports a network, quota, parse, safety, schema, or model error.
  • The response is blank, incomplete, or not valid JSON.
  • The app falls back to a simpler output instead of the expected generated card.

Likely causes

  • The API key field is empty, copied with extra spaces, or belongs to a project without the expected access.
  • The selected model name, API version, or request parameters do not match what the current API supports.
  • Quota, rate limits, temporary service capacity, or network timeouts interrupt the request.
  • The prompt or output trips a safety block, returns no usable content, or does not match the expected schema.
  • The generation asks for strict JSON, but the response includes prose, markdown, or truncated content.

Step-by-step checks

  1. Confirm that the API key field is not empty and does not include leading or trailing spaces.
  2. Run the app's basic connection test before trying a full card.
  3. Run a mini card test with short input to separate API access from long prompt complexity.
  4. Check that the selected model name is one of the app's current options.
  5. Classify the error as network, quota, parse, safety, schema, model, or empty-response behavior.
  6. Try the same short input with normal generation to see whether the model can produce any usable output.
  7. If fallback output appears, treat it as a recovery state and inspect what failed before regenerating the full card.

Fixes and fallback options

  • For API key or permission errors, review the provider console and the app's API setup field.
  • For quota or rate-limit errors, wait, reduce repeated requests, or use the provider's documented quota controls.
  • For JSON parse errors, shorten the request, reduce optional sections, and regenerate a smaller card first.
  • For safety blocks, rewrite the card concept in a safer, clearer, less ambiguous way.
  • For temporary 500-level service issues, retry later or switch to another app-supported model when available.
  • When generation still fails, use fallback output or manual entry, then improve the card with the guides.

Available Gemini models, API versions, limits, and safety behavior can change by project and over time. Avoid assuming that one model name or error code explanation is permanent.

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