feat: add configurable tool loop detection

docs/gateway/configuration-reference.md

@@ -1417,6 +1417,39 @@ Controls elevated (host) exec access:
 }
 ```
 
+### `tools.loopDetection`
+
+Tool-loop safety checks are **disabled by default**. Set `enabled: true` to activate detection.
+Settings can be defined globally in `tools.loopDetection` and overridden per-agent at `agents.list[].tools.loopDetection`.
+
+```json5
+{
+  tools: {
+    loopDetection: {
+      enabled: true,
+      historySize: 30,
+      warningThreshold: 10,
+      criticalThreshold: 20,
+      globalCircuitBreakerThreshold: 30,
+      detectors: {
+        genericRepeat: true,
+        knownPollNoProgress: true,
+        pingPong: true,
+      },
+    },
+  },
+}
+```
+
+- `historySize`: max tool-call history retained for loop analysis.
+- `warningThreshold`: repeating no-progress pattern threshold for warnings.
+- `criticalThreshold`: higher repeating threshold for blocking critical loops.
+- `globalCircuitBreakerThreshold`: hard stop threshold for any no-progress run.
+- `detectors.genericRepeat`: warn on repeated same-tool/same-args calls.
+- `detectors.knownPollNoProgress`: warn/block on known poll tools (`process.poll`, `command_status`, etc.).
+- `detectors.pingPong`: warn/block on alternating no-progress pair patterns.
+- If `warningThreshold >= criticalThreshold` or `criticalThreshold >= globalCircuitBreakerThreshold`, validation fails.
+
 ### `tools.web`
 
 ```json5