Tip: `CLAUDE_CODE_WEBFETCH_CACHE_TTL_MS` Makes the WebFetch URL Cache Tunable for the First Time
Claude Code Changelog·medium signal
Claude Code 2.1.233 added an environment variable to configure the WebFetch session URL cache TTL, with the default left unchanged at 15 minutes. That default is a real problem for any agent that polls a status page, a CI endpoint or a changelog inside a long session — it silently serves you a stale page for a quarter hour. Set it low for monitoring loops; raise it for research runs that re-read the same primary sources repeatedly and want the token savings.