Indexing API returns error 500

Hi,

We just installed the indexing API plugin. Configuration was pretty straightforward.

1. Activated the API.
2. Created a service account
3. Authorized the service account in GSC
4. Uploaded the JSON key to WordPress.

When testing via the Indexing API Console, it’s throwing an error 500, with a verbose description that Googling suggests might be specific to WordPress. This appears to be true for all kinds of pages, posts, categories, etc. I’m unable to replicate the HTTP error directly in Chrome.

10:33:32 AM update https://northcutt.com/seo/
{
  "readyState": 4,
  "responseText": "The site is experiencing technical difficulties.",
  "status": 500,
  "statusText": "Internal Server Error"
}
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