[BUG] ValueError: Level 'debug' does not exist when running basic-memory with Python 3.12+ / macOS

[rgazeredo]

Bug Description

When running basic-memory mcp (version 0.14.2) on macOS with Python 3.12.11, I receive the following error:

ValueError: Level 'debug' does not exist

This error occurs in basic_memory/utils.py during loguru setup, specifically at the call:

logger.add(..., level="debug", ...)

---

Steps To Reproduce

Steps to reproduce the behavior:

1. Install basic-memory version 0.14.2 via pip or pipx with Python 3.12.11
2. Run: basic-memory mcp
3. The CLI configures loguru logging
4. Execution fails with a ValueError stating "Level 'debug' does not exist"

---

Expected Behavior

basic-memory mcp should start the MCP server successfully without raising an exception. The logging configuration should accept a standard log level "DEBUG".

---

Actual Behavior

Instead of launching, execution fails with the traceback:

ValueError: Level 'debug' does not exist

This happens because loguru does not recognize "debug" (lowercase) as a valid log level name. Its API (logger.add(..., level="...")) expects uppercase strings like "DEBUG" ([GitHub][1], [GitHub][2], [Loguru][3]).

---

Environment

• OS: macOS (Apple Silicon)
• Python version: 3.12.11 (via Homebrew)
• Basic‑memory version: 0.14.2
• Installation method: installed via pipx --python /opt/homebrew/bin/python3.12
• Claude Desktop version (if applicable): N/A

---

Additional Context

• No existing issue was found regarding this error in the official repository.
• loguru requires log level names in uppercase (e.g. "DEBUG"); lowercase "debug" is invalid and triggers ValueError ([Loguru][3]).
• The issue appears on Python ≥ 3.12, showing incompatibility with lowercase default log level.

---

Possible Solution

As a workaround, edit basic_memory/utils.py and change:

logger.add(..., level="debug", ...)

to:

logger.add(..., level="DEBUG", ...)

For a long‑term fix, the codebase should normalize log level inputs or default to uppercase. Introducing automated tests for Python 3.12+ would also help prevent this in future releases.