2504 Design B2066ea2

Technical Design: fix-task-list-id

Metadata

• Feature: fix-task-list-id
• Status: DRAFT
• Created: 2026-01-31

1. Overview

1.1 Summary

Fix CLAUDE_CODE_TASK_LIST_ID propagation so solo-dev orchestrators and workers share the same default task list. Currently, workers get feature as fallback while orchestrators use the default list, causing task coordination to silently fail.

1.2 Goals

• Workers inherit orchestrator's CLAUDE_CODE_TASK_LIST_ID (or absence thereof)
• Teams can still opt-in by exporting the env var before starting Claude Code
• No behavioral change for team workflows that already set the env var

1.3 Non-Goals

• Changing the task list ID format or naming convention
• Adding new env vars or config options

2. Architecture

2.1 Root Cause

Orchestrator (no env var set)  →  uses DEFAULT task list
    │
    └── spawns worker with CLAUDE_CODE_TASK_LIST_ID=feature
            → uses FEATURE task list  ← MISMATCH

2.2 Fix Strategy

Remove feature fallback from all 4 spawn methods in launcher.py. Only propagate the env var if the orchestrator actually has it set. Remove the safety net in worker_main.py that forces it. Update rush.core.md container template.

2.3 After Fix

Solo:  orchestrator(default) → worker(default)     ✓
Team:  orchestrator(feat)    → worker(feat)         ✓

3. Detailed Changes

3.1 launcher.py — 4 spawn sites

Lines ~462-466, ~734-737 (subprocess):

# Before:
worker_env.setdefault(
    "CLAUDE_CODE_TASK_LIST_ID",
    os.environ.get("CLAUDE_CODE_TASK_LIST_ID", feature),
)
# After:
task_list_id = os.environ.get("CLAUDE_CODE_TASK_LIST_ID")
if task_list_id:
    worker_env.setdefault("CLAUDE_CODE_TASK_LIST_ID", task_list_id)

Lines ~974-976, ~1543-1545 (container):

# Before:
"CLAUDE_CODE_TASK_LIST_ID": os.environ.get("CLAUDE_CODE_TASK_LIST_ID", feature),
# After:
**({"CLAUDE_CODE_TASK_LIST_ID": os.environ["CLAUDE_CODE_TASK_LIST_ID"]}
   if "CLAUDE_CODE_TASK_LIST_ID" in os.environ else {}),

3.2 worker_main.py — line ~116-117

Delete:

if not env.get("CLAUDE_CODE_TASK_LIST_ID"):
    env["CLAUDE_CODE_TASK_LIST_ID"] = args.feature

3.3 zerg:rush.core.md — line ~178

# Before:
-e CLAUDE_CODE_TASK_LIST_ID=$FEATURE \
# After:
-e CLAUDE_CODE_TASK_LIST_ID=${CLAUDE_CODE_TASK_LIST_ID:-} \

3.4 CLAUDE.md — doc updates

• Rule 5: note inheritance behavior
• Drift check #5: lower threshold from ≥5 to ≥4

4. Key Decisions

Decision: Omit env var when unset (vs empty string)

Context: When orchestrator has no CLAUDE_CODE_TASK_LIST_ID, should workers get an empty string or no env var at all?

Decision: No env var (omit entirely)

Rationale: Empty string may be interpreted differently than absence by Claude Code internals. Omitting preserves the default behavior exactly.

5. Implementation Plan

File Ownership

6. Risk Assessment

7. Verification

# 1. All existing tests pass
python -m pytest tests/ -x -q

# 2. launcher.py no longer has feature fallback
grep -n "CLAUDE_CODE_TASK_LIST_ID" zerg/launcher.py
# Expect: ALLOWED_ENV_VARS entry + conditional sets (no `feature` fallback)

# 3. worker_main.py no longer forces the env var
grep -c "CLAUDE_CODE_TASK_LIST_ID" zerg/worker_main.py
# Expect: 0

# 4. Drift detection still passes (with updated threshold)
count=$(grep -c "CLAUDE_CODE_TASK_LIST_ID" zerg/launcher.py)
echo "launcher.py — $count CLAUDE_CODE_TASK_LIST_ID refs (expect ≥4)"