{"version":"2.1.317","anchor":"deferred-mcp-tool-lookup-waits-for-sdk-servers","canonical_anchor":"deferred-mcp-tool-lookup-waits-for-sdk-servers","heading":"Claude Code waits for SDK-provided MCP servers before reporting their tools missing","tier":"notice","area":"SDK","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317\/e\/deferred-mcp-tool-lookup-waits-for-sdk-servers","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.317","markdown":"### Claude Code waits for SDK-provided MCP servers before reporting their tools missing\n\nWhen looking up a tool from an MCP server supplied through the SDK, Claude Code now keeps waiting until that server has connected\n\n**What**\n\nMCP servers give Claude extra tools, and a program using the SDK can supply its own. When Claude Code looks up one of their tools, it now keeps checking while that server is still connecting. Before, this wait only applied to other kinds of MCP servers.\n\n**Why**\n\nThis may stop \"tool not found\" errors just after an SDK-supplied server starts.\n\n- Area: SDK\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}