docs: update

docs/API.md

@@ -15,12 +15,18 @@ The SPORE system provides a comprehensive RESTful API for monitoring and control
 
 | Endpoint | Method | Description | Response |
 |----------|--------|-------------|----------|
-| `/api/node/status` | GET | System resource information and API endpoint registry | System metrics and API catalog |
+| `/api/node/status` | GET | System resource information | System metrics |
 | `/api/node/endpoints` | GET | API endpoints and parameters | Detailed endpoint specifications |
 | `/api/cluster/members` | GET | Cluster membership and node health information | Cluster topology and health status |
 | `/api/node/update` | POST | Handle firmware updates via OTA | Update progress and status |
 | `/api/node/restart` | POST | Trigger system restart | Restart confirmation |
 
+### Monitoring API
+
+| Endpoint | Method | Description | Response |
+|----------|--------|-------------|----------|
+| `/api/monitoring/resources` | GET | CPU, memory, filesystem, and uptime | System resource metrics |
+
 ### Network Management API
 
 | Endpoint | Method | Description | Response |
@@ -140,7 +146,7 @@ Controls the execution state of individual tasks. Supports enabling, disabling,
 
 #### GET /api/node/status
 
-Returns comprehensive system resource information including memory usage, chip details, and a registry of all available API endpoints.
+Returns comprehensive system resource information including memory usage and chip details. For a list of available API endpoints, use `/api/node/endpoints`.
 
 **Response Fields:**
 - `freeHeap`: Available RAM in bytes
@@ -168,7 +174,7 @@ Returns comprehensive system resource information including memory usage, chip d
 
 #### GET /api/node/endpoints
 
-Returns detailed information about all available API endpoints, including their parameters, types, and validation rules.
+Returns detailed information about all available API endpoints, including their parameters, types, and validation rules. Methods are returned as strings (e.g., "GET", "POST").
 
 **Response Fields:**
 - `endpoints[]`: Array of endpoint capability objects
@@ -236,6 +242,54 @@ Initiates an over-the-air firmware update. The firmware file should be uploaded
 
 Triggers a system restart. The response will be sent before the restart occurs.
 
+### Monitoring
+
+#### GET /api/monitoring/resources
+
+Returns real-time system resource metrics.
+
+Response Fields:
+- `cpu.current_usage`: Current CPU usage percent
+- `cpu.average_usage`: Average CPU usage percent
+- `cpu.max_usage`: Max observed CPU usage
+- `cpu.min_usage`: Min observed CPU usage
+- `cpu.measurement_count`: Number of measurements
+- `cpu.is_measuring`: Whether measurement is active
+- `memory.free_heap`: Free heap bytes
+- `memory.total_heap`: Total heap bytes (approximate)
+- `memory.heap_fragmentation`: Fragmentation percent (0 on ESP8266)
+- `filesystem.total_bytes`: LittleFS total bytes
+- `filesystem.used_bytes`: Used bytes
+- `filesystem.free_bytes`: Free bytes
+- `filesystem.usage_percent`: Usage percent
+- `system.uptime_ms`: Uptime in milliseconds
+Example Response:
+```json
+{
+  "cpu": {
+    "current_usage": 3.5,
+    "average_usage": 2.1,
+    "max_usage": 15.2,
+    "min_usage": 0.0,
+    "measurement_count": 120,
+    "is_measuring": true
+  },
+  "memory": {
+    "free_heap": 48748,
+    "total_heap": 81920,
+    "heap_fragmentation": 0
+  },
+  "filesystem": {
+    "total_bytes": 65536,
+    "used_bytes": 10240,
+    "free_bytes": 55296,
+    "usage_percent": 15.6
+  },
+  "system": {
+    "uptime_ms": 123456
+  }
+}
+```
 ### Network Management
 
 #### GET /api/network/status