improve exception message for response validation error.

Makefile

@@ -1,16 +1,25 @@
+VENV_DIR = venv
+PYTHON = python3.12
+PIP = $(VENV_DIR)/bin/pip
+PYTHON_VENV = $(VENV_DIR)/bin/python
+TOX = $(VENV_DIR)/bin/tox
+PRE_COMMIT = $(VENV_DIR)/bin/pre-commit
+
+
 .PHONY: venv test tox format clean build install upload_to_testpypi upload_to_pypi all
 
 
-venv:
+venv: venv/pyvenv.cfg $(PKG_DIR)
 	# Create virtual environment.
-	python3.12 -m venv venv
-	./venv/bin/pip3 -q install --upgrade pip setuptools wheel
-	./venv/bin/pip3 -q install -e ".[dev]"
-	./venv/bin/pip3 -q install -e .
+
+venv/pyvenv.cfg: pyproject.toml $(PKG_DIR)
+	$(PYTHON) -m venv $(VENV_DIR)
+	$(PIP) -q install --upgrade pip wheel
+	$(PIP) -q install -e ".[dev]" && $(PIP) -q install -e .
 
 format: venv
 	# Run checking and formatting sources.
-	./venv/bin/pre-commit run -a
+	$(PRE_COMMIT) run -a
 
 test: venv
 	# Run pytest.
@@ -19,22 +28,22 @@ test: venv
 
 tox: venv
 	# Testing project via several Python versions.
-	./venv/bin/tox
+	$(TOX)
 
 clean:
 	rm -rf dist/
 	rm -rf src/Flask_First.egg-info
 
 build: clean venv
-	./venv/bin/python3 -m build
+	$(PYTHON_VENV) -m build
 
 install: build
-	./venv/bin/pip install dist/Flask-First-*.tar.gz
+	$(PIP) install dist/Flask-First-*.tar.gz
 
 upload_to_testpypi: build
-	./venv/bin/python3 -m twine upload --repository testpypi dist/*
+	$(PYTHON_VENV) -m twine upload --repository testpypi dist/*
 
 upload_to_pypi: build
-	./venv/bin/python3 -m twine upload --repository pypi dist/*
+	$(PYTHON_VENV) -m twine upload --repository pypi dist/*
 
 all: venv tox build

pyproject.toml

@@ -27,15 +27,15 @@ version = "0.18.1"
 
 [project.optional-dependencies]
 dev = [
-  "bandit==1.7.7",
-  "build==1.1.1",
-  "mypy==1.8.0",
-  "pre-commit==3.6.2",
-  "pytest==8.1.2",
-  "pytest-cov==4.1.0",
+  "bandit==1.7.9",
+  "build==1.2.1",
+  "mypy==1.11.2",
+  "pre-commit==3.8.0",
+  "pytest==8.3.2",
+  "pytest-cov==5.0.0",
   "python-dotenv==1.0.1",
-  "tox==4.13.0",
-  "twine==5.0.0"
+  "tox==4.18.0",
+  "twine==5.1.1"
 ]
 
 [project.urls]