RemoteTrigger / Scheduled Tasks API returns 500 — cannot list, update, or delete triggers

Bug Description

The RemoteTrigger (Scheduled Tasks) API at /v1/code/triggers returns HTTP 500 for all read/update operations. The web UI at https://claude.ai/code/scheduled also shows "예약된 작업을 불러오지 못했습니다" (Failed to load scheduled tasks).

Environment

• Plan: Claude Code Max (Opus 4.6)
• OS: Windows 10 Pro (Git Bash terminal)
• Claude Code CLI version: Latest as of 2026-04-04

Steps to Reproduce

1. A trigger was previously created successfully (ID: trig_018dSenjseCdmEckj8Kjqrjg) and ran correctly for ~24 hours
2. Now all API operations fail:

LIST triggers

RemoteTrigger action=list
→ HTTP 500: {"error":{"message":"An internal server error occurred","type":"api_error"}}

GET specific trigger

RemoteTrigger action=get, trigger_id=trig_018dSenjseCdmEckj8Kjqrjg
→ HTTP 500: same error

UPDATE trigger

RemoteTrigger action=update, trigger_id=trig_018dSenjseCdmEckj8Kjqrjg, body={"enabled": false}
→ HTTP 500: same error

CREATE new trigger

RemoteTrigger action=create, body={valid job_config with ccr...}
→ HTTP 400: "Your plan gets 1 hourly cloud scheduled session. Disable or delete an existing schedule to continue."

Impact

• Stuck state: The existing trigger occupies the 1-trigger slot but cannot be listed, modified, or deleted
• No workaround: Neither the API nor the web UI (claude.ai/code/scheduled) can load or manage triggers
• Web UI error: "예약된 작업을 불러오지 못했습니다" (Failed to load scheduled tasks)

Expected Behavior

• list should return the existing trigger
• update should allow disabling/modifying the trigger
• Web UI should display and allow deletion of the trigger

Request IDs (for server-side debugging)

• list: req_011CZiKCBwBZMuGHGEsuNWNg
• get: req_011CZiKCc6Ekvx6zEVNjeGw7
• update: req_011CZiKU9hgvVvzGZ6aPntUw
• create (limit): req_011CZiKT9FNXeNeDmuKe1sgv