diff --git a/README.md b/README.md
index bd49522..934aac3 100644
--- a/README.md
+++ b/README.md
@@ -30,4 +30,9 @@ Results will be shown in the console:
 # of services with a valid URL: 691/819 (84%)
 # of services with a valid organisation: 812/819 (99%)
 # of services with a valid contact: 598/819 (73%)
-```
\ No newline at end of file
+```
+
+### Updating the list of APIs
+
+An insomnium JSON file (`./insomoum.json`) is used to store the list of endpoints the tool fetches data from. To edit the list using a UI, download and install the [Insomnium](https://github.com/ArchGPT/insomnium) REST API client and open the JSON file.
+