v0.43.0

Changed

• validation::is_valid_mcp_tool_format accepts the server-only MCP form. The function is in the Public/Unstable tier and its signature is unchanged, but it now returns true for mcp__<server> where it previously returned false, so a downstream caller relying on the stricter behavior will see a change. Whitespace in the server segment is newly rejected.

Fixed

• [[overrides]] had no effect on any skill rule. Reported as Windows-specific path matching, but the platform was incidental: SkillValidator's internal ValidationContext stored the &LintConfig that PerFileLintConfig derefs to, so the per-file override layer was discarded before any is_rule_enabled call. Every AS-* and CC-SK-* rule ignored [[overrides]] on all platforms, with no way to suppress one for a single file. The context now holds the per-file view, and an end-to-end regression test covers the case (closes #1277).
• CC-SK-008/CC-AG-009/CC-AG-010 rejected the documented server-only MCP form. mcp__playwright errored while the doc-equivalent mcp__playwright__* passed, even though the permissions reference lists both as valid ways to name every tool from one server. Both forms are now accepted. A glob in the server segment (mcp__supabase-*, mcp__*) is still rejected, since a rule must name a specific configured server, and the tool segment may still glob (mcp__github__get_*).
• Unknown-tool false positives on current built-in tools. Workflow, Artifact, ReportFindings, SendUserFile, and EndConversation are in the built-in tools reference but were missing from CC-SK-008's known-tools list. CC-AG-009/010's list was further behind - 26 documented tools absent, including the Cron*/Task* families, PowerShell, LSP, ToolSearch, and the worktree and MCP-resource tools - so a subagent declaring any of them failed. Tools that subagents never receive stay listed: Claude Code filters those from the resolved pool rather than rejecting the name.