PreToolUse matchers miss external MCP namespaces; raw output enters context

Current state (v1.0.103)

hooks/hooks.json PreToolUse covers: Bash, WebFetch, Read, Grep, Agent, and three mcp__plugin_context-mode_context-mode__ctx_* tools. PostToolUse matcher is broad (Bash|...|mcp__) and catches everything post-execution.

Symptom

Large MCP returns reach the agent unfiltered before PostToolUse fires. PreToolUse can't route them through ctx_execute or warn the agent first, because the matcher list doesn't include them.

Concrete examples of large unbounded returns:

• mcp__slack-* channel history, conversation search (50+ messages)
• mcp__plugin_telegram__* message content, attachments
• mcp__claude_ai_Google_Drive__* file content, search results
• any future notion / obsidian-cli style MCP server

Proposal

Add PreToolUse matchers for external MCP namespaces. Two shapes:

1. A broader pattern: mcp__(?!plugin_context-mode_).*. Covers all external MCPs and avoids recursing into context-mode.
2. A per-namespace allowlist that grows as new MCPs are added.

Option 1 scales without manual upkeep. pretooluse.mjs already runs for ctx_* calls, so the existing routing logic should apply.

Workaround

Local edit to hooks/hooks.json, lost on plugin upgrade.

Happy to PR option 1 if that's the direction you'd take.