feat: cross-tool user identity via MAGNET_USER_ID / X-Magnet-User-ID

[helinakdogan]

Summary

• proxy/main.py: chat_completions now reads X-Magnet-User-ID header first; falls back to x-session-id when absent. The resolved value is used as raw_user_id before project-scoped hashing.
• sdk/magnet/client.py: Added _default_user_id (read from MAGNET_USER_ID env var) in __init__. Added _resolve_user_id() helper. All public methods (add, async_add, search, get_all, delete_all, get_profile, get_injection, force_reflect, get_pending_signals, get_recommended_model) now accept user_id: str | None = None and resolve it via the helper.
• Also fixed a pre-existing argument-order bug in get_recommended_model (get_profile(project_id, user_id) → get_profile(user_id, project_id)).

Usage

SDK:

export MAGNET_USER_ID=alice@company.com

memory = BehavioralMemory(...)
memory.add(messages)  # user_id resolved from env

Proxy:

X-Magnet-User-ID: alice@company.com

Same user profile is recognized across Claude Code, Cursor, Codex — any tool that sets the same identifier.

Test plan

• SDK: call add() without user_id with MAGNET_USER_ID set — profile stored under correct tenant
• SDK: call add() without MAGNET_USER_ID and without user_id — raises ValueError
• Proxy: send request with X-Magnet-User-ID header — same hash as a request with that value as x-session-id
• Proxy: send request without X-Magnet-User-ID — falls back to x-session-id as before

🤖 Generated with Claude Code