{"name":"CLAUDE_CODE_SPAWN_TIMESTAMP_MS","slug":"claude-code-spawn-timestamp-ms","family":"env","title":"Environment variables","noun":"environment variable","description":"Epoch time in milliseconds at which the process was spawned, parsed as a base 10 integer; an empty or non-numeric value is ignored, and `CCR_SPAWN_TIMESTAMP_MS` takes precedence when it parses. Claude Code uses it to report `spawn_to_first_checkpoint_ms` in the `tengu_startup_perf` event, as the start anchor (`spawn_stamp`) for time since session start when no session-switch time is known, and in remote sessions as the starting point of the auth cache warm-up clock.","description_source":"code","described_by":{"bundle":"2.1.286","author":"claude-opus-5-5"},"presence":{"first_seen":"2.1.152","removed_in":null,"in_current_build":true,"newest_mined":"2.1.309","builds":137,"mined_builds":150,"first_cited":null},"aliases":[],"entries":[],"entries_total":0,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"CLAUDE_CODE_SPAWNED_BY_SERVER","slug":"claude-code-spawned-by-server","description":"The Artifact tool's setting entry no longer names `CLAUDE_CODE_DISABLE_ARTIFACT`, though the variable name still appears elsewhere in Claude Code"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/claude-code-spawn-timestamp-ms","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}