{"version":"2.1.323","anchor":"tool-list-permission-hook-denied-tools-are-filtered-from-th","canonical_anchor":"tool-list-permission-hook-denied-tools-are-filtered-from-th","heading":"Tools blocked by your deny rules are now removed from a security hook's tool list","tier":"notice","area":"Permissions","scope":"both","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.323\/e\/tool-list-permission-hook-denied-tools-are-filtered-from-th","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.323","markdown":"### Tools blocked by your deny rules are now removed from a security hook's tool list\n\nA built-in security hook now strips any tool matching `permissions.deny`, including whole MCP servers, from the tool list\n\n**Unclear.** It is not known which sessions run this security hook, so it may not apply to every setup.\n\n**What**\n\n`permissions.deny` is the setting that lists tool uses Claude must refuse. A built-in security hook (a check Claude Code runs on the list of available tools) now removes any tool matching those rules from that list. That includes rules that block every tool from one MCP server, an add-on that supplies extra tools. It does this whether the step before it succeeded or failed. If the settings cannot be read, it reports \"sec-default could not read the tool list\".\n\n**Why**\n\nTools you have denied no longer slip back into the list through this hook.\n\n- Area: Permissions\n- Names: `permissions.deny`\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: both\n- Heads-up: no"}