{"version":"2.1.315","anchor":"mcp-serve-tool-host-permission-rules-from-unreadable-settin","canonical_anchor":"mcp-serve-tool-host-permission-rules-from-unreadable-settin","heading":"Tool server mode keeps permission rules when a settings file cannot be read","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.315\/e\/mcp-serve-tool-host-permission-rules-from-unreadable-settin","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.315","markdown":"### Tool server mode keeps permission rules when a settings file cannot be read\n\nWhen Claude Code runs as a tool server, a settings file that fails to load no longer silently drops all its permission rules\n\n**What**\n\nWith `mcp serve`, Claude Code acts as a tool server that other programs can call. Permission rules are settings that say which actions are allowed, refused, or need asking. Loading them from your settings files now handles failures differently:\n\n- If a settings file is briefly unreadable, Claude Code uses the version it last read.\n\n- If a settings file did not load at all, Claude Code logs that none of that file's permission rules apply and carries on with the other settings file.\n\nBefore, an unreadable file simply gave no rules.\n\n**Why**\n\nThis stops refusal and ask rules from quietly disappearing just because a settings file could not be read for a moment, and makes it visible when a file's rules are not in force.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}