diff --git a/backend/app/schemas/agents.py b/backend/app/schemas/agents.py
index 6713199..17ec7c1 100644
--- a/backend/app/schemas/agents.py
+++ b/backend/app/schemas/agents.py
@@ -84,7 +84,7 @@ class AgentBase(SQLModel):
     heartbeat_config: dict[str, Any] | None = Field(
         default=None,
         description="Runtime heartbeat behavior overrides for this agent.",
-        examples=[{"interval_seconds": 30, "missing_tolerance": 120}],
+        examples=[{"every": "10m", "target": "last", "includeReasoning": False}],
     )
     identity_profile: dict[str, Any] | None = Field(
         default=None,
@@ -173,7 +173,7 @@ class AgentUpdate(SQLModel):
     heartbeat_config: dict[str, Any] | None = Field(
         default=None,
         description="Optional heartbeat policy override.",
-        examples=[{"interval_seconds": 45}],
+        examples=[{"every": "15m", "target": "last", "includeReasoning": False}],
     )
     identity_profile: dict[str, Any] | None = Field(
         default=None,
diff --git a/backend/app/services/openclaw/provisioning.py b/backend/app/services/openclaw/provisioning.py
index 02545cc..ff47851 100644
--- a/backend/app/services/openclaw/provisioning.py
+++ b/backend/app/services/openclaw/provisioning.py
@@ -113,10 +113,15 @@ def _templates_root() -> Path:
     return _repo_root() / "templates"
 
 
+_VALID_HEARTBEAT_KEYS = frozenset(DEFAULT_HEARTBEAT_CONFIG.keys())
+
+
 def _heartbeat_config(agent: Agent) -> dict[str, Any]:
     merged = DEFAULT_HEARTBEAT_CONFIG.copy()
     if isinstance(agent.heartbeat_config, dict):
-        merged.update(agent.heartbeat_config)
+        for key, value in agent.heartbeat_config.items():
+            if key in _VALID_HEARTBEAT_KEYS:
+                merged[key] = value
     return merged