diff --git a/docs/user-guide/gravitational-harmonics/index.rst b/docs/user-guide/gravitational-harmonics/index.rst
index 0e9f188cd..dc4fe4b1c 100644
--- a/docs/user-guide/gravitational-harmonics/index.rst
+++ b/docs/user-guide/gravitational-harmonics/index.rst
@@ -3,6 +3,15 @@ Gravitational Harmonics
##########################
Here, we show how to use Swiftest's Gravitational Harmonics capabilities.
+Swiftest uses `SHTOOLS ` to compute the gravitational harmonics coefficients for a given body and calculate it's associated acceleration kick.
+The coefficients can be computed in a number of ways:
+- Using the axes measurements of the body ( :func: `clm_from_ellipsoid `)
+- Using a surface relief grid ( :func: `clm_from_relief `).
+
+ * This function is still in development and may not work as expected.
+
+- Manually entering the coefficients when adding the central body ( :func: `add_body `)
+
This is based on ``/spherical_harmonics_cb`` in ``swiftest/examples``.