What probably matters to youSection of the release
What
An environment variable is a named value set before a program starts. Claude Code now reads CLAUDE_CODE_PLUGIN_REMOTE_MCP_REACHABLE_HOSTS_HINT as a comma-separated list of hosts. It is used when Claude Code finds remote MCP servers (outside tool servers) that come with plugins. Each entry can be:
a plain host name in ASCII letters
a wildcard name such as *.example.com
an IP address
Entries must not include a scheme such as https:// or a port. If any entry cannot be read, Claude Code logs a warning and ignores the whole list until every entry is valid. The plugin server lookup can also be told to ignore the list.
Why
This lets whatever runs Claude Code tell it which hosts remote plugin MCP servers can actually reach. One bad entry turns the whole hint off, so check the list if it seems to have no effect.
Two sources agreeTwo things we can check say the same as this entry.
Anthropic's release notes agreeFixed a case where certificate errors behind a TLS-inspecting proxy persisted when the proxy itself is reached over https://
The name it cites is new in this buildNew in this build: CLAUDE_CODE_PLUGIN_REMOTE_MCP_REACHABLE_HOSTS_HINT
