diff --git a/pyproject.toml b/pyproject.toml
index 534cd36..33c23fc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "acstore"
-version = "20260515"
+version = "20260516"
 description = "Attribute Container Storage (ACStore)"
 maintainers = [
     { name = "Log2Timeline maintainers", email = "log2timeline-maintainers@googlegroups.com" },
@@ -31,5 +31,10 @@ line-length = 88
 target-version = ["py310"]
 include = "\\.pyi?$"
 
+[tool.docformatter]
+black = true
+non-cap = []
+non-strict = true
+
 [tool.setuptools]
 package-dir = {"acstore" = "acstore"}
diff --git a/tox.ini b/tox.ini
index d86664c..03ee521 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py3{10,11,12,13,14},black,coverage,docs,pylint,wheel,yamllint
+envlist = py3{10,11,12,13,14},black,coverage,docformatter,docs,pylint,wheel,yamllint
 
 [testenv]
 allowlist_externals = ./run_tests.py
@@ -37,7 +37,23 @@ deps =
   setuptools >= 65
 commands =
   black --version
-  black --check .
+  black .
+
+[testenv:docformatter]
+skipsdist = True
+pip_pre = True
+passenv =
+  CFLAGS
+  CPPFLAGS
+  LDFLAGS
+setenv =
+  PYTHONPATH = {toxinidir}
+deps =
+  docformatter
+  setuptools >= 65
+commands =
+  docformatter --version
+  docformatter --in-place --recursive acstore tests
 
 [testenv:docs]
 usedevelop = True