Developer Utilities

Gemini API Error Decoder

Decode Gemini API and Antigravity Agent error responses locally with likely causes, fix steps, and retry templates.

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This tool runs locally in your browser. Your input is not sent to a backend or paid API.

Gemini API Error Decoder

Paste a sanitized Gemini API or Antigravity Agent error and get local troubleshooting notes.

Error response

Diagnosis

Category: Authentication
Probable cause: The request is missing a valid Gemini API key, using a key from the wrong project, or running in an environment where GEMINI_API_KEY is not loaded.

Fix steps:
1. Confirm GEMINI_API_KEY exists in the same shell, server, or deployment environment.
2. Verify the key belongs to the Google AI project used for the request.
3. Regenerate the key if it was copied from an old project or exposed accidentally.
4. Retry with a tiny request before testing a full Antigravity Agent workflow.

Retry template:
curl -H "x-goog-api-key: $GEMINI_API_KEY" -H "Content-Type: application/json" https://generativelanguage.googleapis.com/v1beta/models

Detected category: Authentication

Remove API keys, user data, repository names, and private prompts before sharing error output.

How to use

How to use Gemini API Error Decoder

Follow this workflow to complete the task locally without leaving the page.

1
Paste a Gemini API error JSON response, SDK error message, or sanitized terminal output.
2
Run the decoder to identify the likely failure category.
3
Review the probable cause, fix steps, and retry template.
4
Copy the troubleshooting notes into your issue, docs, or local debugging checklist.

Examples

Example inputs

Use these examples to understand common workflows and expected input formats.

API key error

Identify a missing or invalid Gemini API key before changing model code.

{"error":{"code":401,"message":"API key not valid. Please pass a valid API key.","status":"UNAUTHENTICATED"}}

Antigravity Agent preview error

Check whether an Antigravity Agent request failed because of a stale preview ID or wrong API surface.

{"error":{"code":404,"message":"Agent antigravity-preview-05-2026 was not found or is not available for this project.","status":"NOT_FOUND"}}

FAQ

Gemini API Error Decoder FAQ

Answers to common questions about behavior, privacy, and practical usage.

Does Gemini API Error Decoder upload my error response?

No. The decoder runs locally in your browser and does not send pasted API errors to a backend or paid API.

Can this tool fix Gemini API errors automatically?

No. It explains likely causes and practical next steps so you can fix keys, model names, agent IDs, state IDs, request shape, or retry behavior yourself.

Does it support Antigravity Agent errors?

Yes. It includes checks for common Antigravity Agent preview problems such as unknown agent IDs, missing environment IDs, previous_interaction_id issues, and broad task timeouts.

Should I paste real API keys into this tool?

No. Even though the tool runs locally, paste sanitized error output and never include real API keys, secrets, user data, or private repository content.