Update API reference docs

CONTRIBUTING.md

@@ -209,32 +209,14 @@ If it is not yet defined and you have multiple external links pointing to the sa
 
 
 ### Updating the API reference
-If your PR introduces new public modules, or renames existing ones,
-make sure to add them to the `docs/source/api_index.rst` page, so that they are included in the [API reference](target-api), e.g.:
-
-```rst
-API Reference
-=============
-
-Information on specific functions, classes, and methods.
-
-.. rubric:: Modules
-
-.. autosummary::
-    :toctree: api
-    :recursive:
-    :nosignatures:
-
-    movement.move_accessor
-    movement.io.load_poses
-    movement.io.save_poses
-    movement.your_new_module
-```
-
-The API reference is auto-generated by the `sphinx-autodoc` and `sphinx-autosummary` plugins, based on docstrings.
+The API reference is auto-generated by the `docs/make_api_index.py` script, and the `sphinx-autodoc` and `sphinx-autosummary` plugins.
+The script generates the `docs/source/api_index.rst` file containing the list of modules to be included in the [API reference](target-api).
+The plugins then generate the API reference pages for each module listed in `api_index.rst`, based on the docstrings in the source code.
 So make sure that all your public functions/classes/methods have valid docstrings following the [numpydoc](https://numpydoc.readthedocs.io/en/latest/format.html) style.
 Our `pre-commit` hooks include some checks (`ruff` rules) that ensure the docstrings are formatted consistently.
 
+If your PR introduces new modules that should not be documented in the [API reference](target-api), or if there are changes to existing modules that necessitate their removal from the documentation, make sure to update the `exclude_modules` list within the `docs/make_api_index.py` script to reflect these exclusions.
+
 ### Updating the examples
 We use [sphinx-gallery](sphinx-gallery:)
 to create the [examples](target-examples).
@@ -259,14 +241,14 @@ pip install -r docs/requirements.txt
 
 Then, from the root of the repository, run:
 ```sh
-sphinx-build docs/source docs/build
+python docs/make_api_index.py && sphinx-build docs/source docs/build
 ```
 
 You can view the local build by opening `docs/build/index.html` in a browser.
 To refresh the documentation, after making changes, remove the `docs/build` folder and re-run the above command:
 
 ```sh
-rm -rf docs/build && sphinx-build docs/source docs/build
+rm -rf docs/build && python docs/make_api_index.py && sphinx-build docs/source docs/build
 ```
 
 To check that external links are correctly resolved, run: