docs(API): Add API page

Author: tony

docs/api.md

@@ -0,0 +1,25 @@
+(api)=
+
+# API Reference
+
+:::{seealso}
+See {ref}`libvcs's API <libvcs:api>` and {ref}`Quickstart <libvcs:quickstart>` to see how you can control
+VCS systems via python API calls.
+:::
+
+## Internals
+
+:::{warning}
+These APIs are purely internal not covered by versioning policies, they can and will break between versions.
+If you need an internal API stabilized please [file an issue](https://github.com/vcs-python/libvcs/issues).
+:::
+
+## Exceptions
+
+```{eval-rst}
+.. autoexception:: vcspull.exc.VCSPullException
+```
+
+```{eval-rst}
+.. autoexception:: vcspull.exc.MultipleConfigWarning
+```

docs/index.md

@@ -21,6 +21,7 @@ quickstart
 configuration
 config-generation
 cli
+api
 developing
 history