{"version":"2.1.310","anchor":"tool-list-withholds-standard-key-tools-unless-an-unresolved","canonical_anchor":"tool-list-withholds-standard-key-tools-unless-an-unresolved","heading":"Some MCP tools can now be left out of a session's tool list","tier":"notice","area":"MCP","scope":"individual","heads_up":true,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.310\/e\/tool-list-withholds-standard-key-tools-unless-an-unresolved","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.310","markdown":"### Some MCP tools can now be left out of a session's tool list\n\nMCP tools that carry a standard key can now be left out of the tools Claude is offered when a new condition is not met\n\n**Unclear.** It is not clear which MCP tools carry a standard key or what condition decides whether they are kept.\n\n**What**\n\nMCP tools come from outside servers you connect to Claude Code. When Claude Code builds the list of tools Claude may use, it now also leaves out any MCP tool that carries a standard key, an extra label some MCP tools have, whenever a new condition based on the tool list is not met.\n\nThe existing filtering by `--tools` is unchanged. A tool left out that way still produces the warning that it \"is not on this session's --tools list and no deny rule names it; withheld. Name it in --tools to offer it\".\n\n**Why**\n\nSome MCP tools may no longer appear in a session even though nothing you configured removes them.\n\n- Area: MCP\n- Names: `--tools`\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 3\/5\n- Scope: individual\n- Heads-up: yes"}