{"version":"2.1.323","anchor":"mcp-tool-call-refusal-limit-field-in-host-protocol","canonical_anchor":"mcp-tool-call-refusal-limit-field-in-host-protocol","heading":"Host programs can be told an MCP server hit its refusal limit","tier":"notice","area":"SDK","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.323\/e\/mcp-tool-call-refusal-limit-field-in-host-protocol","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.323","markdown":"### Host programs can be told an MCP server hit its refusal limit\n\nHost programs can now get a `refusal_limit` error when an MCP tool call is refused because its server reached a refusal limit\n\n**Unclear.** It is not stated where the refusal limit is set or what value it has.\n\n**What**\n\nA host program is software that embeds Claude Code and answers its permission questions. MCP (Model Context Protocol) servers are add-ons that give Claude extra tools. Error replies sent to hosts can now carry a `refusal_limit` field.\n\nThe field means a tool call was refused without being judged, because that MCP server's checked calls had reached a refusal limit. The error code `mcp_call_refusal_limit` is used for calls that were not staged.\n\n**Why**\n\nHosts can now tell a call refused by this per-server limit apart from other refusals.\n\n- Area: SDK\n- Names: `refusal_limit`\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5\n- Scope: individual\n- Heads-up: no"}