AlgoPhase phase-write can hit the wrong session: reads CLAUDE_SESSION_ID, which Claude Code doesn't expose

[MatiasBarboza]

Symptom

bun ~/.claude/LIFEOS/TOOLS/AlgoPhase.ts <phase> (without --slug) can write the Algorithm phase to a different session's row in work.json than the active one — corrupting the Pulse dashboard's phase / mode-history for an unrelated session.

Root cause

Slug resolution priority (in AlgoPhase.ts):

1. --slug
2. row whose sessionUUID === process.env.CLAUDE_SESSION_ID
3. --uuid
4. most-recent algorithm-mode row across all sessions

Priority 2 reads CLAUDE_SESSION_ID. Per the official env-vars doc, Claude Code exposes neither CLAUDE_SESSION_ID nor CLAUDE_CODE_SESSION_ID as a general Bash env var — the documented session id is CLAUDE_CODE_BRIDGE_SESSION_ID (Remote Control) / CLAUDE_CODE_REMOTE_SESSION_ID (cloud). So priority 2 never matches, and every bare invocation falls through to priority 4, which guesses the most-recently-active algorithm row. With more than one live session, that guess can be wrong — a silent write to the wrong session.

Docs discrepancy worth surfacing

The changelog (v2.1.163) says stdio MCP servers "receive the same CLAUDE_CODE_SESSION_ID as hooks/Bash on --resume" — naming a variable that env-vars.md says isn't exposed (it documents CLAUDE_CODE_BRIDGE_SESSION_ID). The correct session var for a Bash subprocess to read is ambiguous across the official docs.

Suggested fix (two parts; the second needs no env var)

1. Read the documented session var(s) — CLAUDE_CODE_BRIDGE_SESSION_ID / CLAUDE_CODE_REMOTE_SESSION_ID — with fallbacks, instead of the non-exposed CLAUDE_SESSION_ID.
2. Fail closed when resolution is ambiguous (no --slug/--uuid/env match and >1 live algorithm-mode row) instead of guessing the most-recent row. The silent wrong-write is the real harm; refusing + printing an error is strictly safer for a tool that writes state.

I have a tested patch (env-var fallback + fail-closed layering + unit tests) if it's useful.

Environment: reproduced on Linux. The exact session env var differs by surface (CLI vs Agent SDK), so part 2 (surface-independent) is the durable half.

[danielmiessler]

You found a real mis-targeting — resolved structurally rather than patched: AlgoPhase.ts was retired entirely (2026-07-14); phase now writes only via ISA frontmatter, so the wrong-session write path no longer exists. The next release drops the tool. Your fail-closed-over-guessing principle is the right one and shaped that call. You're in the README Credits.