diff --git a/docs/rpc/http/index.mdx b/docs/rpc/http/index.mdx
index ddcaa9649..0392e5605 100644
--- a/docs/rpc/http/index.mdx
+++ b/docs/rpc/http/index.mdx
@@ -29,7 +29,9 @@ To make a JSON-RPC request, send an HTTP POST request with a
 fields:
 
 - `jsonrpc: <string>` - set to `"2.0"`
-- `id: <number>` - a unique client-generated identifying integer
+- `id: <string | number | null>` - a unique identifier for the request,
+  generated by the client. Typically a string or number, though null is
+  technically allowed but not advised
 - `method: <string>` - a string containing the method to be invoked
 - `params: <array>` - a JSON array of ordered parameter values