ModuleNotFoundError: No module named 'httpx' on fresh 0.13.0 install — httpx imported but not declared

[klasnyi]

Summary

A fresh install of 0.13.0 fails on every CLI invocation with ModuleNotFoundError: No module named 'httpx'. httpx is imported at module top level in five modules but is not declared in the project dependencies.

Reproduce

uv tool install "reverse-api-engineer[manual]"
reverse-api-engineer --version

Traceback (most recent call last):
  File "~/.local/bin/reverse-api-engineer", line 4, in <module>
    from reverse_api.cli import main
  File ".../reverse_api/cli.py", line 24, in <module>
    from .engineer import run_reverse_engineering
  File ".../reverse_api/engineer.py", line 23, in <module>
    from .base_engineer import REPORT_CLIENT_VERIFIED_INSTRUCTION, BaseEngineer
  File ".../reverse_api/base_engineer.py", line 14, in <module>
    from .messages import MessageStore
  File ".../reverse_api/messages.py", line 7, in <module>
    from .utils import get_messages_path
  File ".../reverse_api/utils.py", line 11, in <module>
    import httpx
ModuleNotFoundError: No module named 'httpx'

Because the chain starts in cli.py, no entry point survives — not even --version.

Root cause

This is not simply a forgotten dependency: a transitive one disappeared.

httpx used to arrive through mcp. mcp 2.0.0 switched to httpx2>=2.5.0, so httpx is no longer pulled into the environment, and the undeclared import surfaces.

Installed metadata in a fresh environment:

mcp                2.0.0     requires httpx2>=2.5.0   (no httpx)
claude-agent-sdk   0.2.143   does not require httpx

Declared dependencies of reverse-api-engineer 0.13.0 — httpx is absent:

aiohttp, claude-agent-sdk, click, cryptography, pygments,
questionary, requests, rich, setproctitle, watchdog

That is why the bug is invisible in older environments that still resolve mcp 1.x.

Affected modules

Top-level imports:

• reverse_api/utils.py:11
• reverse_api/auto_engineer.py:11
• reverse_api/ollama_runtime.py:17
• reverse_api/opencode_runtime.py:22
• reverse_api/opencode_engineer.py:14

Plus a local import at reverse_api/cli.py:125.

Suggested fix

Add the dependency explicitly in pyproject.toml:

dependencies = [
    ...
    "httpx>=0.27",
]

Pinning mcp<2 would also restore the transitive path, but declaring the direct import is the more robust fix — the code imports httpx directly, so it should own the requirement.

Workaround

uv tool install --with httpx "reverse-api-engineer[manual]"

Environment

macOS (darwin 25.6.0) · Python 3.13 in the uv tool environment · reverse-api-engineer 0.13.0 · mcp 2.0.0 · claude-agent-sdk 0.2.143 · uv 0.11.6