add type checking to tox.ini

Author: ubdbra001

tox.ini

@@ -7,6 +7,7 @@ envlist =
   py310-min
   style
   spellcheck
+  type
 skip_missing_interpreters = true
 
 # Configuration that allows us to split tests across GitHub runners effectively
@@ -15,7 +16,7 @@ python =
   3.10: py310
   3.11: py311
   3.12: py312
-  3.13: py313
+  3.13: py313, type
   3.14: py314
 
 [gh-actions:env]
@@ -87,3 +88,12 @@ runner = uv-venv-runner
 commands =
   fix: codespell -w {posargs}
   !fix: codespell {posargs}
+
+[testenv:type]
+description = Check type consistency
+labels = check
+dependency_groups =
+  types
+skip_install = true
+commands =
+  mypy --strict src tests