{"version":"2.1.307","anchor":"mcp-client-onerror-hook-installed-once-per-client","canonical_anchor":"mcp-client-onerror-hook-installed-once-per-client","heading":"MCP error handling is no longer added more than once per connection","tier":"notice","area":"MCP","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.307\/e\/mcp-client-onerror-hook-installed-once-per-client","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.307","markdown":"### MCP error handling is no longer added more than once per connection\n\nClaude Code now sets up its error handling for an MCP server connection only once, instead of adding it again each time\n\n**What**\n\nMCP (Model Context Protocol) is the standard Claude Code uses to connect to outside servers that give it extra tools. Claude Code adds its own error handling to each MCP connection. It now keeps track of which connections already have it, so it is added only once per connection. Before, it was added again every time.\n\n**Why**\n\nThis stops errors from being handled several times over, for example after a server reconnects.\n\n- Area: MCP\n- Tier: You'll notice\n- Useful: 1\/5\n- Signal: 0\/5\n- Scope: individual\n- Heads-up: no"}