CI caught 3 ACP test failures (tests/acp/test_server.py,
tests/acp/test_mcp_e2e.py). Root cause: routing ACP's tool-surface rebuild
through the shared refresh_agent_mcp_tools helper (added in the round-2 pass)
broke a deliberate, pre-existing ACP contract:
- the ACP tests assert `agent.tools is <get_tool_definitions return>` (object
identity) and an exact get_tool_definitions(enabled_toolsets=[...],
disabled_toolsets=..., quiet_mode=True) call signature; the shared helper
list()-copies and re-derives differently, breaking identity; and
- the tests use a MagicMock agent whose _tool_snapshot_generation is a mock, so
the new `int < published_gen` generation guard raised TypeError and the whole
ACP refresh silently failed.
ACP already preserves memory-provider tools (its own inject call) and excludes
context_engine, so there was no bug to fix there — only over-reach. Reverted ACP
to its original rebuild. (Same lesson as the gateway path: leave call sites that
carry their own tested contract alone; a reviewer's "inert today, fragile" note
meant leave-it, not change-it.)
Also hardened the generation guard defensively: tolerate a non-int
_tool_snapshot_generation (mock / partially-built agent) instead of throwing
TypeError and silently failing the refresh.