{"version":"2.1.257","anchor":"new-check-artifact-addon-tool-local-preview-runtime-dia","canonical_anchor":"new-check-artifact-addon-tool-local-preview-runtime-dia","heading":"New \"check\" artifact addon tool: local preview + runtime diagnostics, dark-launched behind two flags","tier":"soon","area":"Artifacts","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.257\/e\/new-check-artifact-addon-tool-local-preview-runtime-dia","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.257","markdown":"### New \"check\" artifact addon tool: local preview + runtime diagnostics, dark-launched behind two flags\n\nA new check artifact addon previews a page locally and reads viewers' runtime diagnostics, behind two env vars.\n\nA new \"check\" artifact addon tool (`addon: \"check\"`) offers local page preview plus runtime diagnostics for viewers, described as letting you \"preview a page locally and read viewers' runtime diagnostics.\" It's added to the addon list alongside the existing comments and data artifact addons, but only exposed when either `CLAUDE_CODE_ARTIFACT_VERIFY` (or the `tengu_osier_pylon_trace` gate) or `CLAUDE_CODE_ARTIFACT_PREVIEW` (or the `tengu_cobalt_plinth_aspen` gate) is enabled. The verify path is forced off whenever `CLAUDE_CODE_REMOTE` is set, and the preview path additionally requires a headless-Chrome finder module to be compiled into the build, otherwise it throws \"artifact preview is not compiled into this build.\" All paths are off by default.\n\n- Flag `tengu_osier_pylon_trace`: Not enough to say (read for one account on one subscription tier against v2.1.257; this account: no value returned, anonymous baseline: no value returned, compiled default: off) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Flag `tengu_cobalt_plinth_aspen`: Not enough to say (read for one account on one subscription tier against v2.1.257; this account: no value returned, anonymous baseline: no value returned, compiled default: off) These values were read against a different version of Claude Code, so treat them as the nearest reading available instead of one taken on this release.\n- Area: Artifacts\n- Names: `CLAUDE_CODE_ARTIFACT_VERIFY`, `CLAUDE_CODE_ARTIFACT_PREVIEW`\n- Tier: Nothing to try yet\n- Useful: 5\/5\n- Signal: 5\/5\n- Present in the build but not switched on"}