What
MCP (Model Context Protocol) servers are outside programs that give Claude extra tools. When Claude Code's own config includes a "memory" MCP server for account memory, any other server with that name is now removed from your server list. Names are compared after normalising them.
- The removed servers are recorded as
reservedNameRefusalsand passed to the/mcpdialog. - Pending or rejected project approvals for a refused name are dropped.
/mcpno longer shows "No MCP servers configured" when the only thing left to show is such a refusal.- A warning notification for these refusals has been added, but in this build it has nothing to show, so no warning appears yet.
Why
If you have your own MCP server called "memory", it will disappear in sessions that have account memory. /mcp no longer claims you have no servers configured when this is the reason the list is short.
Names in the bundle/mcp
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Confirmed since
Anthropic's documentation has since written up /mcp, on Hooks reference.
* **[MCP tool hooks](#mcp-tool-hook-fields)** (`type: "mcp_tool"`): call a tool on a configured [MCP server](/docs/en/mcp). The tool's text output is treated like command-hook stdout.hooks see the edit
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
Which names count as reserved, what policy turns the refusal on, and what `/mcp` shows in place of the empty message are not settled.
Anthropic's documentation agrees
Anthropic's documentation has since written up /mcp, on Hooks reference.
Anthropic's release notes agree
Fixed MCP sign-in for a server with no valid URL failing with an opaque SDK error; /mcp no longer offers Authenticate for such servers