fix: Chronicle creds docs (#1368)

* Add credentials section

* Update if -> If

exporter/chronicleexporter/README.md

@@ -36,7 +36,28 @@ Predefined regions include multiple global locations such as `Europe Multi-Regio
 
 ### Log Type
 
-if the `attributes["log_type"]` field is present in the log, and maps to a known chronicle `log_type` the exporter will use the value of that field as the log type. If the `attributes["log_type"]` field is not present, the exporter will use the value of the `log_type` configuration field as the log type.
+If the `attributes["log_type"]` field is present in the log, and maps to a known Chronicle `log_type` the exporter will use the value of that field as the log type. If the `attributes["log_type"]` field is not present, the exporter will use the value of the `log_type` configuration field as the log type.
+
+## Credentials
+
+This exporter requires a Google Cloud service account with access to the Chronicle API. The service account must have access to the following endpoint(s):
+
+The base endpoint is `https://malachiteingestion-pa.googleapis.com`
+
+Alternatively, if a `region` is specified:
+
+| Region                       | Endpoint                                                            |
+| ---------------------------- | ------------------------------------------------------------------- |
+| `Europe Multi-Region`        | `https://malachiteingestion-pa-europe.googleapis.com`               |
+| `Frankfurt`                  | `https://malachiteingestion-pa-europe-west3.googleapis.com`         |
+| `London`                     | `https://malachiteingestion-pa-europe-west2.googleapis.com`         |
+| `Singapore`                  | `https://malachiteingestion-pa-asia-southeast1.googleapis.com`      |
+| `Sydney`                     | `https://malachiteingestion-pa-australia-southeast1.googleapis.com` |
+| `Tel Aviv`                   | `https://malachiteingestion-pa-europe-west4.googleapis.com`         |
+| `United States Multi-Region` | `https://malachiteingestion-pa.googleapis.com`                      |
+| `Zurich`                     | `https://malachiteingestion-pa-europe-west6.googleapis.com`         |
+
+For additional information on accessing Chronicle, see the [Chronicle documentation](https://cloud.google.com/chronicle/docs/reference/ingestion-api#getting_api_authentication_credentials).
 
 ## Example Configuration