{"version":"2.1.281","anchor":"mcp-cache-key-includes-the-mcp-ui-offer","canonical_anchor":"mcp-cache-key-includes-the-mcp-ui-offer","heading":"MCP cache key includes the MCP UI offer","tier":"internal","area":"MCP","url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281\/e\/mcp-cache-key-includes-the-mcp-ui-offer","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281","markdown":"### MCP cache key includes the MCP UI offer\n\nMCP cache files are now keyed on whether the MCP UI extension was offered, so the two cases are stored separately\n\n**What**\n\nMCP (Model Context Protocol) lets Claude Code connect to outside servers that provide extra tools. Claude Code caches some MCP data in files named after a hash, which is a short fingerprint built from the settings in play. When the MCP UI extension is offered, that hash now includes `offer:io.modelcontextprotocol\/ui`.\n\n**Why**\n\nIn practice, cached data made while the UI extension was offered is kept apart from cached data made without it. A result from one case is not reused for the other.\n\n- Area: MCP\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5"}