Add blurb

encukou · encukou · commit 66d64bef6f3f · 2023-02-07T14:14:18.000+01:00
diff --git a/Misc/NEWS.d/next/C API/2023-02-07-14-14-15.gh-issue-101101.qTD3SH.rst b/Misc/NEWS.d/next/C API/2023-02-07-14-14-15.gh-issue-101101.qTD3SH.rst
@@ -0,0 +1,4 @@
+Introduced the :ref:`Unstable C API tier <unstable-c-api>`, intended for
+low-level tools like debuggers and JIT compilers. This API may change in
+each minor release of CPython without deprecation warnings. Its contents are
+marked by the ``PyUnstable_`` prefix in names.
