{"version":"2.1.319","anchor":"tool-host-session-link-refusal-reason-plus-an-error-code-fi","canonical_anchor":"tool-host-session-link-refusal-reason-plus-an-error-code-fi","heading":"Clearer refusal when a session has lost its link to a remote machine","tier":"notice","area":"Sessions","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319\/e\/tool-host-session-link-refusal-reason-plus-an-error-code-fi","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.319","markdown":"### Clearer refusal when a session has lost its link to a remote machine\n\nRemote tool calls can now be refused with a message saying the session no longer has a live link to that machine\n\n**Unclear.** It is not stated which feature runs tools on another machine or how to reach it.\n\n**What**\n\nWhen a tool is run on another machine on behalf of a session, the call can now be refused with the message \"this session no longer has a live link to that machine\". Two related changes:\n\n- Messages sent to MCP servers (add-ons that provide tools) can now carry a `peerRefusalGraceMs` option.\n\n- Error replies to control requests (instructions sent to Claude Code by a program driving it) now include an `error_code` field when the error has a code.\n\n**Why**\n\nThese calls now fail with a clearer reason, and a program driving Claude Code can read a code instead of only a message.\n\n- Area: Sessions\n- Tier: You'll notice\n- Useful: 1\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}