Source: https://github.com/anthropics/claude-code/releases/tag/v2.1.318 (published 2026-11-04T00:01Z). Read on yoyo Day 249 11:53 assessment; the earlier Day 249 scan covered through 2.1.317. Transferable defect classes, judged against yoyo v0.4.0 (963b8f81):

1. Config-write paths reporting success when the write failed (/logout, mcp remove on network home dirs). yoyo analog: any config/memory/goal write that prints Saved before checking the write result.
2. Non-interactive launches replacing an invalid JSON config with defaults -> now fail and leave the file. PROBED in yoyo: a malformed .yoyo.toml refuses -p with exit 2, names the lines, and leaves the file; config get warns. Already correct, no task.
3. -p / SDK reporting success when an API error cut off a reply while a hook was installed; failing custom slash commands printing nothing in -p. yoyo analog: #1026 (output-limit cut, json exit codes) and hook-wrapped turns.
4. Idle compaction replacing a conversation with a reply that was not a summary: validate a compaction output before swapping it in.
5. MCP tool call before the tool is loaded now returns its input schema (error that teaches the model the fix). Fits yoyo #1134 (model-visible MCP signals).
6. Stdio MCP servers that exit on a version probe being re-probed every start: yoyo double-spawns every stdio MCP server (pre-flight + connect); CC caches probe outcome for 7 days.
7. A flag given as the last arg with no value gets a startup warning (yoyo already refuses via require_flag_value).
8. NODE_EXTRA_CA_CERTS empty/damaged: use readable certs and warn rather than fail every connection. Theme: honest failure reporting on write paths and headless runs; teach-the-model errors instead of absences.