ToolSearch blocks all deferred tool access when data exfiltration classifier is temporarily unavailable

Summary

When the data exfiltration classifier goes down, ToolSearch returns an error and blocks all deferred tool loading for the duration of the outage. Since deferred tools cannot be invoked without first loading them via ToolSearch, any MCP tool not already loaded in the session becomes completely inaccessible.

Error message

The data exfiltration classifier is temporarily unavailable, so ToolSearch cannot be used right now.
Wait briefly and then try this action again. If it keeps failing, continue with other tasks that
don't require this action and come back to it later. Note: reading files, searching code, and other
read-only operations do not require the classifier and can still be used.
(dacEnabled=true, hasExtraBody=false)

Steps to reproduce

1. Trigger (or wait for) a temporary DAC outage
2. In a Claude Code session, attempt to call ToolSearch to load any deferred tool
3. Receive the error above
4. All deferred MCP tools remain inaccessible for the session until the classifier recovers

Impact

• Any workflow that relies on deferred tools (e.g., Slack, GitHub, Google Drive MCP) is fully blocked
• The agent cannot recover gracefully — even retrying after a few seconds fails if the outage persists
• No fallback path exists; there's no way to load tools outside of ToolSearch

Expected behavior

One or more of:

1. Graceful degradation: Allow ToolSearch to load tools without classifier check during outage (or with a lower-confidence fallback)
2. Session cache: Tools loaded earlier in the session should remain available regardless of classifier state
3. Better error guidance: If degradation isn't possible, surface a clearer message with which specific tools are still usable

Environment

• Platform: macOS (darwin 25.3.0)
• Session context: mid-session ToolSearch call to load Grep, Glob
• dacEnabled: true, hasExtraBody: false