diff --git a/nix/host-modules/swarm-grafana/dashboards/agents.json b/nix/host-modules/swarm-grafana/dashboards/agents.json
index 2ee0cb4a..85bffbc2 100644
--- a/nix/host-modules/swarm-grafana/dashboards/agents.json
+++ b/nix/host-modules/swarm-grafana/dashboards/agents.json
@@ -5,7 +5,7 @@
   "tags": ["hyperhive", "agents"],
   "timezone": "utc",
   "schemaVersion": 39,
-  "version": 1,
+  "version": 2,
   "editable": true,
   "refresh": "1m",
   "time": {
@@ -715,6 +715,274 @@
           "sort": "desc"
         }
       }
+    },
+    {
+      "id": 40,
+      "type": "stat",
+      "title": "Subagent cost",
+      "description": "sum(increase(claude_code.cost.usage{subagent!=\"\"})). `hive-subagent-mcp` stamps a `subagent=<name>` resource attribute (alongside the parent's own `agent=<name>`) on every claude_code.* sample a spawned subagent turn emits — this label already existed, it just wasn't plotted anywhere.",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "@datasourceUid@"
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 8,
+        "x": 0,
+        "y": 35
+      },
+      "targets": [
+        {
+          "refId": "A",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "@datasourceUid@"
+          },
+          "expr": "sum(increase({__name__=\"claude_code.cost.usage\", hive=~\"$hive\", agent=~\"$agent\", subagent!=\"\"}[$__range]))",
+          "instant": true,
+          "legendFormat": "subagent cost"
+        }
+      ],
+      "fieldConfig": {
+        "defaults": {
+          "unit": "currencyUSD",
+          "decimals": 2,
+          "color": {
+            "mode": "fixed",
+            "fixedColor": "text"
+          },
+          "mappings": []
+        },
+        "overrides": []
+      },
+      "options": {
+        "graphMode": "none",
+        "colorMode": "value",
+        "textMode": "value",
+        "reduceOptions": {
+          "calcs": ["lastNotNull"],
+          "fields": "",
+          "values": false
+        }
+      }
+    },
+    {
+      "id": 41,
+      "type": "stat",
+      "title": "Subagent turns",
+      "description": "claude_code.session.count where subagent!=\"\" — a proxy for subagent turns, same PROXY caveat as the plain 'CLI sessions started' tile above.",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "@datasourceUid@"
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 8,
+        "x": 8,
+        "y": 35
+      },
+      "targets": [
+        {
+          "refId": "A",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "@datasourceUid@"
+          },
+          "expr": "sum(increase({__name__=\"claude_code.session.count\", hive=~\"$hive\", agent=~\"$agent\", subagent!=\"\"}[$__range]))",
+          "instant": true,
+          "legendFormat": "subagent turns"
+        }
+      ],
+      "fieldConfig": {
+        "defaults": {
+          "unit": "short",
+          "decimals": 0,
+          "color": {
+            "mode": "fixed",
+            "fixedColor": "text"
+          },
+          "mappings": []
+        },
+        "overrides": []
+      },
+      "options": {
+        "graphMode": "none",
+        "colorMode": "value",
+        "textMode": "value",
+        "reduceOptions": {
+          "calcs": ["lastNotNull"],
+          "fields": "",
+          "values": false
+        }
+      }
+    },
+    {
+      "id": 42,
+      "type": "stat",
+      "title": "Subagent cost share",
+      "description": "Subagent cost as a fraction of all cost in the selected range — 'basically free' is a claim this tile can actually check.",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "@datasourceUid@"
+      },
+      "gridPos": {
+        "h": 4,
+        "w": 8,
+        "x": 16,
+        "y": 35
+      },
+      "targets": [
+        {
+          "refId": "A",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "@datasourceUid@"
+          },
+          "expr": "sum(increase({__name__=\"claude_code.cost.usage\", hive=~\"$hive\", agent=~\"$agent\", subagent!=\"\"}[$__range])) / sum(increase({__name__=\"claude_code.cost.usage\", hive=~\"$hive\", agent=~\"$agent\"}[$__range]))",
+          "instant": true,
+          "legendFormat": "subagent share"
+        }
+      ],
+      "fieldConfig": {
+        "defaults": {
+          "unit": "percentunit",
+          "decimals": 1,
+          "color": {
+            "mode": "fixed",
+            "fixedColor": "text"
+          },
+          "mappings": []
+        },
+        "overrides": []
+      },
+      "options": {
+        "graphMode": "none",
+        "colorMode": "value",
+        "textMode": "value",
+        "reduceOptions": {
+          "calcs": ["lastNotNull"],
+          "fields": "",
+          "values": false
+        }
+      }
+    },
+    {
+      "id": 43,
+      "type": "bargauge",
+      "title": "Cost by subagent name",
+      "description": "claude_code.cost.usage summed over the selected range, split by the caller-chosen `subagent` name (e.g. an exploration/relabeling task's session name) rather than which agent spawned it.",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "@datasourceUid@"
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 0,
+        "y": 39
+      },
+      "targets": [
+        {
+          "refId": "A",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "@datasourceUid@"
+          },
+          "expr": "sum by (subagent) (increase({__name__=\"claude_code.cost.usage\", hive=~\"$hive\", agent=~\"$agent\", subagent!=\"\"}[$__range]))",
+          "instant": true,
+          "legendFormat": "{{subagent}}"
+        }
+      ],
+      "fieldConfig": {
+        "defaults": {
+          "unit": "currencyUSD",
+          "decimals": 2,
+          "color": {
+            "mode": "fixed",
+            "fixedColor": "purple"
+          },
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "purple",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "options": {
+        "displayMode": "basic",
+        "orientation": "horizontal",
+        "showUnfilled": true,
+        "valueMode": "text",
+        "reduceOptions": {
+          "calcs": ["lastNotNull"],
+          "fields": "",
+          "values": false
+        }
+      }
+    },
+    {
+      "id": 44,
+      "type": "bargauge",
+      "title": "Subagent cost by parent agent",
+      "description": "Same claude_code.cost.usage{subagent!=\"\"}, grouped by the spawning agent's own `agent` label instead — which agent's subagent habit is actually costing something.",
+      "datasource": {
+        "type": "prometheus",
+        "uid": "@datasourceUid@"
+      },
+      "gridPos": {
+        "h": 7,
+        "w": 12,
+        "x": 12,
+        "y": 39
+      },
+      "targets": [
+        {
+          "refId": "A",
+          "datasource": {
+            "type": "prometheus",
+            "uid": "@datasourceUid@"
+          },
+          "expr": "sum by (agent) (increase({__name__=\"claude_code.cost.usage\", hive=~\"$hive\", agent=~\"$agent\", subagent!=\"\"}[$__range]))",
+          "instant": true,
+          "legendFormat": "{{agent}}"
+        }
+      ],
+      "fieldConfig": {
+        "defaults": {
+          "unit": "currencyUSD",
+          "decimals": 2,
+          "color": {
+            "mode": "fixed",
+            "fixedColor": "blue"
+          },
+          "thresholds": {
+            "mode": "absolute",
+            "steps": [
+              {
+                "color": "blue",
+                "value": null
+              }
+            ]
+          }
+        },
+        "overrides": []
+      },
+      "options": {
+        "displayMode": "basic",
+        "orientation": "horizontal",
+        "showUnfilled": true,
+        "valueMode": "text",
+        "reduceOptions": {
+          "calcs": ["lastNotNull"],
+          "fields": "",
+          "values": false
+        }
+      }
     }
   ]
 }