Add OAuth authentication client for HTTPX (#751)

Co-authored-by: Paul Carleton <paulc@anthropic.com>

examples/clients/simple-auth-client/pyproject.toml

@@ -0,0 +1,52 @@
+[project]
+name = "mcp-simple-auth-client"
+version = "0.1.0"
+description = "A simple OAuth client for the MCP simple-auth server"
+readme = "README.md"
+requires-python = ">=3.10"
+authors = [{ name = "Anthropic" }]
+keywords = ["mcp", "oauth", "client", "auth"]
+license = { text = "MIT" }
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: MIT License",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.10",
+]
+dependencies = [
+    "click>=8.0.0",
+    "mcp>=1.0.0",
+]
+
+[project.scripts]
+mcp-simple-auth-client = "mcp_simple_auth_client.main:cli"
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["mcp_simple_auth_client"]
+
+[tool.pyright]
+include = ["mcp_simple_auth_client"]
+venvPath = "."
+venv = ".venv"
+
+[tool.ruff.lint]
+select = ["E", "F", "I"]
+ignore = []
+
+[tool.ruff]
+line-length = 88
+target-version = "py310"
+
+[tool.uv]
+dev-dependencies = ["pyright>=1.1.379", "pytest>=8.3.3", "ruff>=0.6.9"]
+
+[tool.uv.sources]
+mcp = { path = "../../../" }
+
+[[tool.uv.index]]
+url = "https://pypi.org/simple"