cesium-mcp

addLabel

Add property-based text labels to GeoJSON features, returning the label count and success status.

Instructions

Add property-based text labels for GeoJSON features. Returns { success, data: { labelCount: integer }, message? }.

Input Schema

TableJSON Schema

Name	Required	Description
`data`	No	GeoJSON FeatureCollection object
`field`	Yes	Attribute field name for label text (e.g. "name", "population")
`style`	No	Label style (font, fillColor, outlineColor, scale, etc.)
`sessionId`	No	Target browser session ID for multi-browser routing (optional)
`resourceId`	No	Stored GeoJSON resource ID (mutually exclusive with data)

Output Schema

TableJSON Schema

Name	Required	Description	Default
`data`	No
`error`	No
`message`	No
`success`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed2 schema fields changedv1.139.22Oct 1, 2026

addedInput schema / properties / resourceId

Added value: +{
+  "description": "Stored GeoJSON resource ID (mutually exclusive with data)",
+  "maxLength": 200,
+  "minLength": 1,
+  "type": "string"
+}

changedInput schema / required

Previous value: -[
-  "data",
-  "field"
-]New value: +[
+  "field"
+]

Changed2 schema fields changedv1.139.19Aug 19, 2026

changedInput schema / properties / data / properties / features / items / properties / geometry / oneOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "description": "Coordinate tuple [longitude, latitude, optional height]",
-        "maxItems": 3,
-        "minItems": 2,
-        "prefixItems": [
-          {
-            "description": "Longitude in decimal degrees",
-            "maximum": 180,
-            "minimum": -180,
-            "type": "number"
-          },
-          {
-            "description": "Latitude in decimal degrees",
-            "maximum": 90,
-            "minimum": -90,
-            "type": "number"
-          },
-          {
-            "description": "Optional height in meters",
-            "maximum": 50000000,
-            "minimum": -12000,
-            "type": "number"
-          }
-        ],
-        "type": "array"
-      },
-      "type": {
-        "const": "Point"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "items": {
-          "description": "Coordinate tuple [longitude, latitude, optional height]",
-          "maxItems": 3,
-          "minItems": 2,
-          "prefixItems": [
-            {
-              "description": "Longitude in decimal degrees",
-              "maximum": 180,
-              "minimum": -180,
-              "type": "number"
-            },
-            {
-              "description": "Latitude in decimal degrees",
-              "maximum": 90,
-              "minimum": -90,
-              "type": "number"
-            },
-            {
-              "description": "Optional height in meters",
-              "maximum": 50000000,
-              "minimum": -12000,
-              "type": "number"
-            }
-          ],
-          "type": "array"
-        },
-        "minItems": 2,
-        "type": "array"
-      },
-      "type": {
-        "const": "LineString"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "items": {
-          "items": {
-            "description": "Coordinate tuple [longitude, latitude, optional height]",
-            "maxItems": 3,
-            "minItems": 2,
-            "prefixItems": [
-              {
-                "description": "Longitude in decimal degrees",
-                "maximum": 180,
-                "minimum": -180,
-                "type": "number"
-              },
-              {
-                "description": "Latitude in decimal degrees",
-                "maximum": 90,
-                "minimum": -90,
-                "type": "number"
-              },
-              {
-                "description": "Optional height in meters",
-                "maximum": 50000000,
-                "minimum": -12000,
-                "type": "number"
-              }
-            ],
-            "type": "array"
-          },
-          "minItems": 4,
-          "type": "array"
-        },
-        "minItems": 1,
-        "type": "array"
-      },
-      "type": {
-        "const": "Polygon"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "description": "Coordinate tuple [longitude, latitude, optional height]",
+        "items": {
+          "type": "number"
+        },
+        "maxItems": 3,
+        "minItems": 2,
+        "prefixItems": [
+          {
+            "description": "Longitude in decimal degrees",
+            "maximum": 180,
+            "minimum": -180,
+            "type": "number"
+          },
+          {
+            "description": "Latitude in decimal degrees",
+            "maximum": 90,
+            "minimum": -90,
+            "type": "number"
+          },
+          {
+            "description": "Optional height in meters",
+            "maximum": 50000000,
+            "minimum": -12000,
+            "type": "number"
+          }
+        ],
+        "type": "array"
+      },
+      "type": {
+        "const": "Point"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "items": {
+          "description": "Coordinate tuple [longitude, latitude, optional height]",
+          "items": {
+            "type": "number"
+          },
+          "maxItems": 3,
+          "minItems": 2,
+          "prefixItems": [
+            {
+              "description": "Longitude in decimal degrees",
+              "maximum": 180,
+              "minimum": -180,
+              "type": "number"
+            },
+            {
+              "description": "Latitude in decimal degrees",
+              "maximum": 90,
+              "minimum": -90,
+              "type": "number"
+            },
+            {
+              "description": "Optional height in meters",
+              "maximum": 50000000,
+              "minimum": -12000,
+              "type": "number"
+            }
+          ],
+          "type": "array"
+        },
+        "minItems": 2,
+        "type": "array"
+      },
+      "type": {
+        "const": "LineString"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "items": {
+          "items": {
+            "description": "Coordinate tuple [longitude, latitude, optional height]",
+            "items": {
+              "type": "number"
+            },
+            "maxItems": 3,
+            "minItems": 2,
+            "prefixItems": [
+              {
+                "description": "Longitude in decimal degrees",
+                "maximum": 180,
+                "minimum": -180,
+                "type": "number"
+              },
+              {
+                "description": "Latitude in decimal degrees",
+                "maximum": 90,
+                "minimum": -90,
+                "type": "number"
+              },
+              {
+                "description": "Optional height in meters",
+                "maximum": 50000000,
+                "minimum": -12000,
+                "type": "number"
+              }
+            ],
+            "type": "array"
+          },
+          "minItems": 4,
+          "type": "array"
+        },
+        "minItems": 1,
+        "type": "array"
+      },
+      "type": {
+        "const": "Polygon"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  }
+]

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "additionalProperties": false,
+  "properties": {
+    "data": {
+      "additionalProperties": false,
+      "properties": {
+        "labelCount": {
+          "minimum": 0,
+          "type": "integer"
+        }
+      },
+      "required": [
+        "labelCount"
+      ],
+      "type": "object"
+    },
+    "error": {
+      "type": "string"
+    },
+    "message": {
+      "type": "string"
+    },
+    "success": {
+      "type": "boolean"
+    }
+  },
+  "required": [
+    "success"
+  ],
+  "type": "object"
+}

Changed7 schema fields changedv1.139.18Aug 12, 2026

removedInput schema / $schema

Removed value: -"http://json-schema.org/draft-07/schema#"

removedInput schema / properties / data / properties / features / items / properties / geometry / anyOf

Removed value: -[
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "anyOf": [
-          {
-            "items": [
-              {
-                "description": "Longitude in decimal degrees",
-                "maximum": 180,
-                "minimum": -180,
-                "type": "number"
-              },
-              {
-                "description": "Latitude in decimal degrees",
-                "maximum": 90,
-                "minimum": -90,
-                "type": "number"
-              }
-            ],
-            "maxItems": 2,
-            "minItems": 2,
-            "type": "array"
-          },
-          {
-            "items": [
-              {
-                "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/0/properties/coordinates/anyOf/0/items/0"
-              },
-              {
-                "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/0/properties/coordinates/anyOf/0/items/1"
-              },
-              {
-                "description": "Optional height in meters",
-                "maximum": 50000000,
-                "minimum": -12000,
-                "type": "number"
-              }
-            ],
-            "maxItems": 3,
-            "minItems": 3,
-            "type": "array"
-          }
-        ],
-        "description": "Coordinate tuple [longitude, latitude, optional height]"
-      },
-      "type": {
-        "const": "Point",
-        "type": "string"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "items": {
-          "anyOf": [
-            {
-              "items": [
-                {
-                  "description": "Longitude in decimal degrees",
-                  "maximum": 180,
-                  "minimum": -180,
-                  "type": "number"
-                },
-                {
-                  "description": "Latitude in decimal degrees",
-                  "maximum": 90,
-                  "minimum": -90,
-                  "type": "number"
-                }
-              ],
-              "maxItems": 2,
-              "minItems": 2,
-              "type": "array"
-            },
-            {
-              "items": [
-                {
-                  "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/1/properties/coordinates/items/anyOf/0/items/0"
-                },
-                {
-                  "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/1/properties/coordinates/items/anyOf/0/items/1"
-                },
-                {
-                  "description": "Optional height in meters",
-                  "maximum": 50000000,
-                  "minimum": -12000,
-                  "type": "number"
-                }
-              ],
-              "maxItems": 3,
-              "minItems": 3,
-              "type": "array"
-            }
-          ],
-          "description": "Coordinate tuple [longitude, latitude, optional height]"
-        },
-        "minItems": 2,
-        "type": "array"
-      },
-      "type": {
-        "const": "LineString",
-        "type": "string"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "coordinates": {
-        "items": {
-          "items": {
-            "anyOf": [
-              {
-                "items": [
-                  {
-                    "description": "Longitude in decimal degrees",
-                    "maximum": 180,
-                    "minimum": -180,
-                    "type": "number"
-                  },
-                  {
-                    "description": "Latitude in decimal degrees",
-                    "maximum": 90,
-                    "minimum": -90,
-                    "type": "number"
-                  }
-                ],
-                "maxItems": 2,
-                "minItems": 2,
-                "type": "array"
-              },
-              {
-                "items": [
-                  {
-                    "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/2/properties/coordinates/items/items/anyOf/0/items/0"
-                  },
-                  {
-                    "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/2/properties/coordinates/items/items/anyOf/0/items/1"
-                  },
-                  {
-                    "description": "Optional height in meters",
-                    "maximum": 50000000,
-                    "minimum": -12000,
-                    "type": "number"
-                  }
-                ],
-                "maxItems": 3,
-                "minItems": 3,
-                "type": "array"
-              }
-            ],
-            "description": "Coordinate tuple [longitude, latitude, optional height]"
-          },
-          "minItems": 4,
-          "type": "array"
-        },
-        "minItems": 1,
-        "type": "array"
-      },
-      "type": {
-        "const": "Polygon",
-        "type": "string"
-      }
-    },
-    "required": [
-      "type",
-      "coordinates"
-    ],
-    "type": "object"
-  }
-]

addedInput schema / properties / data / properties / features / items / properties / geometry / oneOf

Added value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "description": "Coordinate tuple [longitude, latitude, optional height]",
+        "maxItems": 3,
+        "minItems": 2,
+        "prefixItems": [
+          {
+            "description": "Longitude in decimal degrees",
+            "maximum": 180,
+            "minimum": -180,
+            "type": "number"
+          },
+          {
+            "description": "Latitude in decimal degrees",
+            "maximum": 90,
+            "minimum": -90,
+            "type": "number"
+          },
+          {
+            "description": "Optional height in meters",
+            "maximum": 50000000,
+            "minimum": -12000,
+            "type": "number"
+          }
+        ],
+        "type": "array"
+      },
+      "type": {
+        "const": "Point"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "items": {
+          "description": "Coordinate tuple [longitude, latitude, optional height]",
+          "maxItems": 3,
+          "minItems": 2,
+          "prefixItems": [
+            {
+              "description": "Longitude in decimal degrees",
+              "maximum": 180,
+              "minimum": -180,
+              "type": "number"
+            },
+            {
+              "description": "Latitude in decimal degrees",
+              "maximum": 90,
+              "minimum": -90,
+              "type": "number"
+            },
+            {
+              "description": "Optional height in meters",
+              "maximum": 50000000,
+              "minimum": -12000,
+              "type": "number"
+            }
+          ],
+          "type": "array"
+        },
+        "minItems": 2,
+        "type": "array"
+      },
+      "type": {
+        "const": "LineString"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "coordinates": {
+        "items": {
+          "items": {
+            "description": "Coordinate tuple [longitude, latitude, optional height]",
+            "maxItems": 3,
+            "minItems": 2,
+            "prefixItems": [
+              {
+                "description": "Longitude in decimal degrees",
+                "maximum": 180,
+                "minimum": -180,
+                "type": "number"
+              },
+              {
+                "description": "Latitude in decimal degrees",
+                "maximum": 90,
+                "minimum": -90,
+                "type": "number"
+              },
+              {
+                "description": "Optional height in meters",
+                "maximum": 50000000,
+                "minimum": -12000,
+                "type": "number"
+              }
+            ],
+            "type": "array"
+          },
+          "minItems": 4,
+          "type": "array"
+        },
+        "minItems": 1,
+        "type": "array"
+      },
+      "type": {
+        "const": "Polygon"
+      }
+    },
+    "required": [
+      "type",
+      "coordinates"
+    ],
+    "type": "object"
+  }
+]

removedInput schema / properties / data / properties / features / items / properties / properties / anyOf

Removed value: -[
-  {
-    "additionalProperties": {},
-    "type": "object"
-  },
-  {
-    "type": "null"
-  }
-]

addedInput schema / properties / data / properties / features / items / properties / properties / type
```
Added value: +[
+  "object",
+  "null"
+]
```
removedInput schema / properties / data / properties / features / items / properties / type / type
```
Removed value: -"string"
```
removedInput schema / properties / data / properties / type / type
```
Removed value: -"string"
```

Changed7 schema fields changedv1.139.17Jul 29, 2026

changedInput schema / properties / data / additionalProperties
```
Previous value: -{}New value: +false
```

addedInput schema / properties / data / properties

Added value: +{
+  "features": {
+    "items": {
+      "additionalProperties": false,
+      "properties": {
+        "geometry": {
+          "anyOf": [
+            {
+              "additionalProperties": false,
+              "properties": {
+                "coordinates": {
+                  "anyOf": [
+                    {
+                      "items": [
+                        {
+                          "description": "Longitude in decimal degrees",
+                          "maximum": 180,
+                          "minimum": -180,
+                          "type": "number"
+                        },
+                        {
+                          "description": "Latitude in decimal degrees",
+                          "maximum": 90,
+                          "minimum": -90,
+                          "type": "number"
+                        }
+                      ],
+                      "maxItems": 2,
+                      "minItems": 2,
+                      "type": "array"
+                    },
+                    {
+                      "items": [
+                        {
+                          "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/0/properties/coordinates/anyOf/0/items/0"
+                        },
+                        {
+                          "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/0/properties/coordinates/anyOf/0/items/1"
+                        },
+                        {
+                          "description": "Optional height in meters",
+                          "maximum": 50000000,
+                          "minimum": -12000,
+                          "type": "number"
+                        }
+                      ],
+                      "maxItems": 3,
+                      "minItems": 3,
+                      "type": "array"
+                    }
+                  ],
+                  "description": "Coordinate tuple [longitude, latitude, optional height]"
+                },
+                "type": {
+                  "const": "Point",
+                  "type": "string"
+                }
+              },
+              "required": [
+                "type",
+                "coordinates"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "coordinates": {
+                  "items": {
+                    "anyOf": [
+                      {
+                        "items": [
+                          {
+                            "description": "Longitude in decimal degrees",
+                            "maximum": 180,
+                            "minimum": -180,
+                            "type": "number"
+                          },
+                          {
+                            "description": "Latitude in decimal degrees",
+                            "maximum": 90,
+                            "minimum": -90,
+                            "type": "number"
+                          }
+                        ],
+                        "maxItems": 2,
+                        "minItems": 2,
+                        "type": "array"
+                      },
+                      {
+                        "items": [
+                          {
+                            "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/1/properties/coordinates/items/anyOf/0/items/0"
+                          },
+                          {
+                            "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/1/properties/coordinates/items/anyOf/0/items/1"
+                          },
+                          {
+                            "description": "Optional height in meters",
+                            "maximum": 50000000,
+                            "minimum": -12000,
+                            "type": "number"
+                          }
+                        ],
+                        "maxItems": 3,
+                        "minItems": 3,
+                        "type": "array"
+                      }
+                    ],
+                    "description": "Coordinate tuple [longitude, latitude, optional height]"
+                  },
+                  "minItems": 2,
+                  "type": "array"
+                },
+                "type": {
+                  "const": "LineString",
+                  "type": "string"
+                }
+              },
+              "required": [
+                "type",
+                "coordinates"
+              ],
+              "type": "object"
+            },
+            {
+              "additionalProperties": false,
+              "properties": {
+                "coordinates": {
+                  "items": {
+                    "items": {
+                      "anyOf": [
+                        {
+                          "items": [
+                            {
+                              "description": "Longitude in decimal degrees",
+                              "maximum": 180,
+                              "minimum": -180,
+                              "type": "number"
+                            },
+                            {
+                              "description": "Latitude in decimal degrees",
+                              "maximum": 90,
+                              "minimum": -90,
+                              "type": "number"
+                            }
+                          ],
+                          "maxItems": 2,
+                          "minItems": 2,
+                          "type": "array"
+                        },
+                        {
+                          "items": [
+                            {
+                              "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/2/properties/coordinates/items/items/anyOf/0/items/0"
+                            },
+                            {
+                              "$ref": "#/properties/data/properties/features/items/properties/geometry/anyOf/2/properties/coordinates/items/items/anyOf/0/items/1"
+                            },
+                            {
+                              "description": "Optional height in meters",
+                              "maximum": 50000000,
+                              "minimum": -12000,
+                              "type": "number"
+                            }
+                          ],
+                          "maxItems": 3,
+                          "minItems": 3,
+                          "type": "array"
+                        }
+                      ],
+                      "description": "Coordinate tuple [longitude, latitude, optional height]"
+                    },
+                    "minItems": 4,
+                    "type": "array"
+                  },
+                  "minItems": 1,
+                  "type": "array"
+                },
+                "type": {
+                  "const": "Polygon",
+                  "type": "string"
+                }
+              },
+              "required": [
+                "type",
+                "coordinates"
+              ],
+              "type": "object"
+            }
+          ]
+        },
+        "id": {
+          "type": [
+            "string",
+            "number"
+          ]
+        },
+        "properties": {
+          "anyOf": [
+            {
+              "additionalProperties": {},
+              "type": "object"
+            },
+            {
+              "type": "null"
+            }
+          ],
+          "description": "Feature attributes used for labels and thematic styling"
+        },
+        "type": {
+          "const": "Feature",
+          "type": "string"
+        }
+      },
+      "required": [
+        "type",
+        "geometry",
+        "properties"
+      ],
+      "type": "object"
+    },
+    "type": "array"
+  },
+  "type": {
+    "const": "FeatureCollection",
+    "type": "string"
+  }
+}

addedInput schema / properties / data / required
```
Added value: +[
+  "type",
+  "features"
+]
```
addedInput schema / properties / field / maxLength
```
Added value: +100
```
addedInput schema / properties / field / minLength
```
Added value: +1
```
changedInput schema / properties / style / additionalProperties
```
Previous value: -{}New value: +false
```

addedInput schema / properties / style / properties

Added value: +{
+  "backgroundColor": {
+    "description": "CSS color such as #3B82F6 or rgba(59,130,246,0.8)",
+    "maxLength": 64,
+    "minLength": 1,
+    "type": "string"
+  },
+  "fillColor": {
+    "description": "CSS color such as #3B82F6 or rgba(59,130,246,0.8)",
+    "maxLength": 64,
+    "minLength": 1,
+    "type": "string"
+  },
+  "font": {
+    "maxLength": 100,
+    "minLength": 1,
+    "type": "string"
+  },
+  "outlineColor": {
+    "description": "CSS color such as #3B82F6 or rgba(59,130,246,0.8)",
+    "maxLength": 64,
+    "minLength": 1,
+    "type": "string"
+  },
+  "outlineWidth": {
+    "maximum": 10,
+    "minimum": 0,
+    "type": "number"
+  },
+  "pixelOffset": {
+    "items": {
+      "maximum": 1000,
+      "minimum": -1000,
+      "type": "number"
+    },
+    "maxItems": 2,
+    "minItems": 2,
+    "type": "array"
+  },
+  "scale": {
+    "exclusiveMinimum": 0,
+    "maximum": 10,
+    "type": "number"
+  },
+  "showBackground": {
+    "type": "boolean"
+  }
+}

Changed4 schema fields changedv1.139.14Apr 30, 2026

changedInput schema / properties / data / description

Previous value: -"GeoJSON FeatureCollection 对象"New value: +"GeoJSON FeatureCollection object"

changedInput schema / properties / field / description

Previous value: -"用作标注文本的属性字段名（如 \"name\"、\"population\"）"New value: +"Attribute field name for label text (e.g. \"name\", \"population\")"

addedInput schema / properties / sessionId

Added value: +{
+  "description": "Target browser session ID for multi-browser routing (optional)",
+  "type": "string"
+}

changedInput schema / properties / style / description

Previous value: -"标注样式（font, fillColor, outlineColor, scale 等）"New value: +"Label style (font, fillColor, outlineColor, scale, etc.)"

First observedv1.139.4Mar 15, 2026

TDQS

C2.9/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, and the description adds nothing beyond these. It does not explain the practical consequence of non-idempotency (e.g. whether repeated calls stack duplicate labels) or whether labels persist across sessions, which is the key behavioral question for a non-idempotent mutation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tightly written sentences with the purpose front-loaded and no filler. The trailing return-shape sentence is largely redundant given the tool already has an output schema, which keeps it short of a 5.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With a rich nested input schema, a full output schema and safety annotations, the description only needs to carry purpose and routing. It covers purpose but omits when-to-use routing and any note on non-idempotent behavior, leaving meaningful gaps for a mutation tool in a 30+ tool set.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and all five parameters are documented in the schema, so the baseline is 3. The phrase 'property-based' hints that the field parameter draws from feature properties, but adds no syntax or format detail beyond the schema's own examples.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('Add property-based text labels for GeoJSON features'), which is more precise than a bare 'add label' and implies labels derive from a feature attribute field. It does not, however, differentiate itself from nearby siblings such as addMarker or addGeoJsonLayer, which an agent must disambiguate on its own.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no guidance on when to use this tool versus siblings like addMarker or addGeoJsonLayer, nor when labels are preferable to markers. The mutually exclusive data vs resourceId choice is only implied by the schema, not by the description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.