ACP clients own MCP server configuration via session/new.mcpServers and AcpAgent#configureMcpServers. The ACP session factory previously left enableMCP at its default (true), so createAgentSession ran discoverAndLoadMCPTools on every session/new and the resulting host MCP tools landed in the session tool registry alongside the client-supplied ones. search_tool_bm25 then surfaced only the host tools.
Force enableMCP: false on every session created through createAcpSessionFactory so on-disk discovery is bypassed in ACP mode. Non-ACP modes (omp interactive, print, RPC) keep auto-discovery.
Fixes#1234
roboomp
185615497c