{"version":"2.1.311","anchor":"cached-mcp-servers-count-as-available-if-the-host-listed-the","canonical_anchor":"cached-mcp-servers-count-as-available-if-the-host-listed-the","heading":"Tool calls to cached MCP servers listed by the host are checked against offered tools","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.311\/e\/cached-mcp-servers-count-as-available-if-the-host-listed-the","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.311","markdown":"### Tool calls to cached MCP servers listed by the host are checked against offered tools\n\nCalls to a cached MCP server the host listed are now refused if the tool was not offered, as for connected servers\n\n**What**\n\nMCP (Model Context Protocol) servers provide extra tools to Claude Code. Claude Code refuses a call to a tool the server did not offer. That check used to apply only to servers that were connected. It now also applies to servers Claude Code has cached (kept from an earlier listing) when the host listed them.\n\n**Why**\n\nCalls to those cached servers are now held to the same list of offered tools, so a call to a tool that was not offered is refused.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 1\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}