Expose only selectable tools over MCP server - #127
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The MCP list and call handlers exposed every non-hidden tool, including system tools that agents auto-include based on context. They now gate on AIToolDefinitionEntry.IsSelectable() so system and hidden tools are never listed or callable over MCP, even when ExposeAllTools is true. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
MikeAlhayek
approved these changes
Aug 10, 2026
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Summary
The MCP server list and call handlers (
WithCrestAppsHandlers()) exposed every non-hidden tool, including system tools that agents auto-include based on context. Both handlers now gate onAIToolDefinitionEntry.IsSelectable()(!IsSystemTool && !Hidden), so system and hidden tools are never listed or callable over MCP — even whenExposeAllToolsistrue. Tool instances are unchanged (user-created, always selectable).This restores the intended behavior:
release/1.0filtered only!Hidden, so it also leaked non-hidden system tools; this fix applies the framework's existing selectable-tool concept to MCP.Changes
ResolveAllowedCodeTool) to selectable tools onlyExposeAllToolslisting; system tool rejected by call handlermcp/server.mdexposure section +changelog/1.1.0.mdFixes entryValidation
Co-authored-by: Copilot 223556219+Copilot@users.noreply.github.com