{"version":"2.1.236","anchor":"old-style-mcp-tool-output-rewrites-from-hooks-are-no-longer-","canonical_anchor":"old-style-mcp-tool-output-rewrites-from-hooks-are-no-longer-","heading":"Old-style MCP tool-output rewrites from hooks are no longer applied silently","tier":"notice","area":"Hooks","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.236\/e\/old-style-mcp-tool-output-rewrites-from-hooks-are-no-longer-","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.236","markdown":"### Old-style MCP tool-output rewrites from hooks are no longer applied silently\n\nA hook using only the older MCP output field no longer silently rewrites tool results.\n\n**What**\n\nA PostToolUse hook that sets only the older `updatedMCPToolOutput` field, without the newer `updatedToolOutput`, no longer has its rewrite applied quietly; the result is marked as suppressed instead.\n\n**Details**\n\n- Separately, MCP resource text is now run through a sanitizer before being handed to the model under \"Full contents of resource:\".\n\n**Evidence**\n\n`u.legacyMcpRewriteSuppressed = !0;`\n\n- Area: Hooks\n- Names: `updatedToolOutput`, `updatedMCPToolOutput`\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 3\/5"}