curl --request POST \
  --url <https://charming-raman-uhtak7x69c.projects.oryapis.com/admin/oauth2/introspect> \
  --header 'Authorization: Basic OTU2MzlmMzktOTE4OC00YWZjLTgxNjAtMjUwY2VlNjE2MDI1OlIyanNUZy1yeUhwLmVmNHFQaldKTWtCMlJh' \
  --header 'Content-Type: application/x-www-form-urlencoded' \
  --data token=****my_token*****

But I have a systematic error:

{
  "error": {
    "code": 401,
    "status": "Unauthorized",
    "request": "e57f7039-b9ba-9523-ae93-2120d082a0c1",
    "message": "Access credentials are invalid"
  }
}

Which credential should I provide?

You need to provide an Ory API key in an

Authorization: Bearer xyz

header