The Debug tool: find the cause of errors

When a call fails, the Debug tool can show you exactly why — without digging through your own logs.

1. Go to Tools → Debug (you'll also find the Investigate link by "Recent errors" on the Overview).
2. Find the failed call: pick it in the Recent errors list, or paste the request_id from the error response (the error response also has a debug_url that links straight here).
3. See the full details: path, status code, latency, time and the server message explaining the error — plus a diagnosis and suggestions for fixing it.
4. Many calls can be sent on to the [Playground](playground) with Test the fix in Playground so you can fix and retry.

The server message is gold: it usually says directly what's missing (e.g. a scope or a parameter).