{"version":"2.1.277","anchor":"tool-input-json-parse-failures-now-log-mcp-status-and-richer","canonical_anchor":"tool-input-json-parse-failures-now-log-mcp-status-and-richer","heading":"Tool-input JSON parse failures now log MCP status and richer Zod error detail","tier":"internal","area":"Tool Validation","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.277\/e\/tool-input-json-parse-failures-now-log-mcp-status-and-richer","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.277","markdown":"### Tool-input JSON parse failures now log MCP status and richer Zod error detail\n\nTool-input JSON parse failure logs now show whether the tool was an MCP tool and give richer Zod error detail\n\n**What**\n\nWhen Claude Code fails to parse a tool's input as JSON, the internal telemetry event `tengu_tool_input_json_parse_fail` now records an `isMcp` field noting whether the tool came from an MCP server (a way of connecting external tools to Claude Code). Related error logging for schema-normalization failures (checked with a library called Zod) now includes the tool's display name, the list of specific Zod issue codes, and the length of the error message, instead of a single flattened error string.\n\n**Why**\n\nThis gives more structured detail for diagnosing why a tool call's input failed to parse, without changing what happens for the user in the moment.\n\n- Area: Tool Validation\n- Tier: Under the hood\n- Useful: 1\/5\n- Signal: 1\/5"}