{"version":"2.1.296","anchor":"hook-commands-get-an-on-failure-field-continue-or-block","canonical_anchor":"hook-commands-get-an-on-failure-field-continue-or-block","heading":"Hooks gain an on_failure field, and cloud launches report built-in tool count","tier":"use","area":"Hooks","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.296\/e\/hook-commands-get-an-on-failure-field-continue-or-block","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.296","markdown":"### Hooks gain an on_failure field, and cloud launches report built-in tool count\n\nHook commands accept an on_failure value of continue or block that cloud hook comparison now includes, and cloud launches report built-in tool count\n\n**Unclear.** It is not clear that setting on_failure changes anything yet, since nothing was found that acts on it.\n\n**What**\n\nHooks are commands you configure to run automatically at certain points, for example before a tool runs.\n\n- Hook commands accept a new `on_failure` field, set to `continue` or `block`. It can be left out, and an invalid value falls back to `block`. What reads this field at runtime was not traced, so its effect is not confirmed.\n\n- The signature Claude Code uses to compare cloud hooks now includes `onFailure`, unless it is `block`. Before, it only left out `cloud`.\n\n- When a headless cloud session (one running on Anthropic's servers without the interactive screen) is launched, its launch report now includes `builtin_tools_count`, the number of built-in tools passed in.\n\n**Why**\n\nThe new field suggests hook authors may be able to choose whether a failing hook stops the action or lets it continue. Until it is confirmed to have an effect, treat `block` as the behaviour you get.\n\n- Area: Hooks\n- Names: `on_failure`\n- Tier: Use it now\n- Useful: 5\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}