{"version":"2.1.195","anchor":"hook-matcher-warnings-for-mcp-server-patterns","canonical_anchor":"hook-matcher-warnings-for-mcp-server-patterns","heading":"Hook Matcher Warnings for MCP Server Patterns","tier":null,"area":null,"scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.195\/e\/hook-matcher-warnings-for-mcp-server-patterns","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.195","markdown":"### Hook Matcher Warnings for MCP Server Patterns\n\n**What**\n\nClaude Code now warns at startup if a hook matcher like `mcp__my_server` matches no known tool, because hook matchers are compared as exact strings \u2014 the correct pattern to match all tools from a server is `mcp__my_server__.*`.\n\n**Details**\n\n- Warning message: \"Hook matcher `mcp__server` matches no tool (it is compared as an exact string). To match all tools from this server, use `mcp__server__.*`. See CHANGELOG v2.1.195.\"\n- Only fires once per distinct matcher pattern per session.\n\n**Evidence**\n\nHook matcher warning (search for `\"matches no tool (it is compared as an exact string). To match all tools from this server, use \\`\"`)"}