{"version":"2.1.321","anchor":"remote-mcp-hook-calls-get-clearer-errors-on-oversize-results","canonical_anchor":"remote-mcp-hook-calls-get-clearer-errors-on-oversize-results","heading":"MCP tool hooks now explain when a result is too large","tier":"notice","area":"Hooks","scope":"individual","heads_up":false,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.321\/e\/remote-mcp-hook-calls-get-clearer-errors-on-oversize-results","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.321","markdown":"### MCP tool hooks now explain when a result is too large\n\nWhen an MCP tool hook gets a result that is too large, it now gives no verdict and says the tool must send a smaller answer\n\n**What**\n\nA hook is an action Claude Code runs automatically at set points, and an `mcp_tool` hook does this by calling a tool from an MCP server, an outside program that provides tools. These hooks now run an extra check for refusals specific to the tool. When the tool's result or message is too large, the hook reports an error saying it gave no verdict and that the tool must send a smaller answer if this keeps happening.\n\n**Why**\n\nAn oversized result now leads to a clear outcome, where the hook makes no decision and explains why, instead of a bare error.\n\n- Area: Hooks\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 1\/5\n- Scope: individual\n- Heads-up: no"}