diff --git a/scripts/release.py b/scripts/release.py
index eaea6681b94..055dda01347 100755
--- a/scripts/release.py
+++ b/scripts/release.py
@@ -1200,6 +1200,7 @@ AUTHOR_MAP = {
     "cine.dreamer.one@gmail.com": "LeonSGP43",
     "Lubrsy706@users.noreply.github.com": "Lubrsy706",
     "niyant@spicefi.xyz": "spniyant",
+    "256398740+nicha16@users.noreply.github.com": "nicha16",  # PR #54139 partial salvage (re-register tools after park revival)
     "olafthiele@gmail.com": "olafthiele",
     "oncuevtv@gmail.com": "sprmn24",
     "programming@olafthiele.com": "olafthiele",
diff --git a/tests/tools/test_mcp_parked_self_probe.py b/tests/tools/test_mcp_parked_self_probe.py
new file mode 100644
index 00000000000..95decf096e0
--- /dev/null
+++ b/tests/tools/test_mcp_parked_self_probe.py
@@ -0,0 +1,108 @@
+"""Tests for the parked-server self-probe revival path (#57129).
+
+Parking deregisters a server's tools, so no tool call can reach the
+circuit-breaker half-open probe or ``_signal_reconnect`` — the only
+things that set ``_reconnect_event``. The parked wait must therefore be
+timed: the run task wakes on ``_PARKED_RETRY_INTERVAL`` and attempts one
+revival probe on its own.
+"""
+
+import asyncio
+
+import pytest
+
+
+@pytest.mark.no_isolate
+def test_parked_server_self_probes_and_revives(monkeypatch, tmp_path):
+    """A parked server must revive on its own once the backend recovers,
+    without any explicit _reconnect_event.set()."""
+    monkeypatch.setenv("HERMES_HOME", str(tmp_path))
+
+    from tools import mcp_tool
+    from tools.mcp_tool import MCPServerTask
+
+    monkeypatch.setattr(mcp_tool, "_MAX_RECONNECT_RETRIES", 1)
+    # Keep the self-probe cadence tiny so the test is fast.
+    monkeypatch.setattr(mcp_tool, "_PARKED_RETRY_INTERVAL", 0.05)
+
+    _real_sleep = asyncio.sleep
+
+    async def _fast_sleep(_delay, *a, **kw):
+        await _real_sleep(0)
+
+    monkeypatch.setattr(mcp_tool.asyncio, "sleep", _fast_sleep)
+
+    state = {
+        "transport_calls": 0,
+        "deregistered": 0,
+        "backend_up": False,
+        "revived_registration": 0,
+    }
+
+    async def _scenario():
+        class _Task(MCPServerTask):
+            def _is_http(self):
+                return False
+
+            def _deregister_tools(self):
+                state["deregistered"] += 1
+                self._registered_tool_names = []
+
+            def _register_discovered_tools_if_needed(self):
+                if self._ready.is_set() and not self._registered_tool_names:
+                    state["revived_registration"] += 1
+                    self._registered_tool_names = ["srv__tool"]
+
+            async def _run_stdio(self, config):
+                state["transport_calls"] += 1
+                if state["transport_calls"] == 1:
+                    # First connect succeeds (sets _ready), then dies.
+                    self.session = object()
+                    self._ready.set()
+                    self.session = None
+                    raise RuntimeError("backend outage begins")
+                if not state["backend_up"]:
+                    raise RuntimeError("backend still down")
+                # Backend recovered: establish a session and park in the
+                # lifecycle wait like the real transport does.
+                self.session = object()
+                self._register_discovered_tools_if_needed()
+                await self._wait_for_lifecycle_event()
+
+        task = _Task("srv")
+        task._registered_tool_names = ["srv__tool"]
+
+        run_task = asyncio.ensure_future(task.run({"command": "x"}))
+
+        # Let it exhaust the budget (1 retry) and park.
+        for _ in range(2000):
+            await _real_sleep(0)
+            if state["deregistered"] >= 1:
+                break
+        assert state["deregistered"] >= 1, "server never parked"
+        assert not run_task.done(), "run task exited instead of parking"
+
+        # The backend comes back. NOTHING sets _reconnect_event — revival
+        # must come from the timed self-probe alone.
+        state["backend_up"] = True
+        for _ in range(200):
+            await _real_sleep(0.01)
+            if task.session is not None:
+                break
+
+        assert task.session is not None, (
+            "parked server never self-probed back to life "
+            f"(transport_calls={state['transport_calls']})"
+        )
+        assert state["revived_registration"] >= 1, (
+            "revived server did not re-register its tools"
+        )
+
+        task._shutdown_event.set()
+        task._reconnect_event.set()
+        try:
+            await asyncio.wait_for(run_task, timeout=2)
+        except (asyncio.TimeoutError, asyncio.CancelledError, Exception):
+            run_task.cancel()
+
+    asyncio.run(_scenario())