What probably matters to youSection of the release
Unclear It is not clear what supplies handed_listing or whether this is switched on for ordinary local sessions.
What
MCP servers are outside programs that give Claude Code extra tools. --mcp-config is the option that loads them from JSON files or strings. Two related things changed in how this configuration is read:
File paths: the paths of files given to --mcp-config are now kept for the whole session (flagMcpConfigFilePaths, cleared on reset). For each one that is a file, both the path and its real location on disk are collected and passed to a new registration step, which checks them against the scan of allowed folders. Before, the file was read with no path registration.
Handed listings: a server's config can now include a handed_listing string next to its url. The parser returns these as handedListings, and startup passes them on as handedMcpListings. In headless mode, a listing (its startup handshake plus tools_list, with an at timestamp) is accepted only for a dynamic http server whose URL matches. A listing older than 600 seconds is dropped. When connecting, cached servers can now have their capabilities, server details and instructions filled from a stored handshake. What supplies this data and whether it is switched on was not traced.
Why
A program hosting Claude Code can hand over a server's tool list ahead of time, so Claude Code can skip asking the server for it, which affects how quickly tools are available at startup.
Read from
Names in the bundlehanded_listing
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtIt is not clear what supplies handed_listing or whether this is switched on for ordinary local sessions.
