# lookup_weather

Retrieves comprehensive weather data including current conditions, hourly, and daily forecasts. Specific Data Available: Temperature (Current, Feels Like, Max/Min, Heat Index), Wind (Speed, Gusts, Direction), Celestial Events (Sunrise/Sunset, Moon Phase), Precipitation (Type, Probability, Quantity/QPF), Atmospheric Conditions (UV Index, Humidity, Cloud Cover, Thunderstorm Probability), and Geocoded Location Address. Location & Location Rules (CRITICAL): The location for which weather data is requested is specified using the location field. This field is a 'oneof' structure, meaning you MUST provide a value for ONLY ONE of the three location sub-fields below to ensure an accurate weather data lookup. 1. Geographic Coordinates (lat_lng) * Use it when you are provided with exact lat/lng coordinates. * Example: {"location": {"lat_lng": {"latitude": 34.0522, "longitude": -118.2437}}} // Los Angeles 2. Place ID (place_id) * An unambiguous string identifier (Google Maps Place ID). * The place_id can be fetched from the search_places tool. * Example: {"location": {"place_id": "ChIJLU7jZClu5kcR4PcOOO6p3I0"}} // Eiffel Tower 3. Address String (address) * A free-form string that requires specificity for geocoding. * City & Region: Always include region/country (e.g., "London, UK", not "London"). * Street Address: Provide the full address (e.g., "1600 Pennsylvania Ave NW, Washington, DC"). * Postal/Zip Codes: MUST be accompanied by a country name (e.g., "90210, USA", NOT "90210"). * Example: {"location": {"address": "1600 Pennsylvania Ave NW, Washington, DC"}} Usage Modes: * Current Weather: Provide location only. Do not specify date and hour. * Hourly Forecast: Provide location, date, and hour (0-23). Use for specific times (e.g., "at 5 PM") or terms like "next few hours" or "later today". If the user specifies minute, round down to the nearest hour. Hourly forecast beyond 120 hours from now is not supported. Historical hourly weather is supported up to 24 hours in the past. * Daily Forecast: Provide location and date. Do not specify hour. Use for general day requests (e.g., "weather for tomorrow", "weather on Friday", "weather on 12/25"). If today's date is not in the context, you should clarify it with the user. Daily forecast beyond 10 days including today is not supported. Historical weather is not supported. Parameter Constraints: * Timezones: All date and hour inputs must be relative to the location's local time zone, not the user's time zone. * Date Format: Inputs must be separated into {year, month, day} integers. * Units: Defaults to METRIC. Set units_system to IMPERIAL for Fahrenheit/Miles if the user implies US standards or explicitly requests it. * The grounded output must be attributed to the source using the information from the attribution field when available.

Agent View of the PolicyLayer registry record for `lookup_weather`. HTML page: https://policylayer.com/tools/com-googleapis-mapstools-mcp/lookup-weather

## Facts

- Tool: `lookup_weather`
- Server: Mcp (`https://mapstools.googleapis.com/mcp`) — https://policylayer.com/tools/com-googleapis-mapstools-mcp.md
- Homepage: https://github.com/https://mapstools.googleapis.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 4 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `date` | object | no | Optional. The date of the required weather information. Note: This date is relative to the local timezone of the location specified in the location field. The d |
| `hour` | integer | no | Optional. The hour of the requested weather information, in 24-hour format (0-23). This value is relative to the local timezone of the location specified in the |
| `location` | object | yes | Required. The location to get the weather conditions for. |
| `unitsSystem` | string | no | Optional. The units system to use for the returned weather conditions. If not provided, the returned weather conditions will be in the metric system (default = |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "lookup_weather",
    "arguments": {
      "location": {}
    }
  }
}
```

## Why lookup_weather is rated Low

This tool performs pure data retrieval without side effects. It queries weather information and returns forecasts and current conditions. There is no capability to modify data, execute code, delete resources, or conduct financial transactions. The severity is low because misuse (e.g., requesting weather for many locations) causes minimal harm—only data queries with no destructive or systemic impact.

From the tool's own definition: "Tool description explicitly states it 'Retrieves comprehensive weather data' including temperature, wind, precipitation, atmospheric conditions, and location address."

## Use case

AI agents call lookup_weather to retrieve information from Mcp without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Mcp:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "lookup_weather": {}
  }
}
```

## Other tools on Mcp (4)

- `compute_routes` — Read — https://policylayer.com/tools/com-googleapis-mapstools-mcp/compute-routes.md
- `resolve_maps_urls` — Read — https://policylayer.com/tools/com-googleapis-mapstools-mcp/resolve-maps-urls.md
- `resolve_names` — Read — https://policylayer.com/tools/com-googleapis-mapstools-mcp/resolve-names.md
- `search_places` — Read — https://policylayer.com/tools/com-googleapis-mapstools-mcp/search-places.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=com-googleapis-mapstools-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-googleapis-mapstools-mcp