{"version":"2.1.317","anchor":"malformed-mcp-tool-entries-withheld-from-the-model","canonical_anchor":"malformed-mcp-tool-entries-withheld-from-the-model","heading":"Broken MCP tool entries are no longer offered to Claude","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317\/e\/malformed-mcp-tool-entries-withheld-from-the-model","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317","markdown":"### Broken MCP tool entries are no longer offered to Claude\n\nMCP tools missing a server name or tool name are now left out of what Claude sees, with a one-time warning\n\n**Unclear.** Whether this filtering always runs or depends on a remote switch is not clear.\n\n**What**\n\nMCP servers are add-ons that give Claude extra tools. Claude Code now leaves out any MCP tool entry that has no server name or no tool name, and logs this warning once:\n\n\"At least one MCP tool was not offered to the model: its entry has no server name or tool name. Other MCP tools are not affected.\"\n\nThe same code also records when a resumed session was using a shared MCP key.\n\n**Why**\n\nThis affects which MCP tools Claude can use. If a tool you expect is missing, the warning points to a broken entry.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 1\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}