Open-Meteo MCP Server

JMA Forecast

jma_forecast

Read-onlyIdempotent

Fetch JMA weather forecasts by specifying one model (e.g., jma_msm) per request. For multi-model comparison, make parallel calls with provider-specific tools.

Instructions

Get weather forecast from Japan Meteorological Agency (JMA) models. IMPORTANT: Specify exactly one JMA model in the models parameter (e.g., "jma_msm" or "jma_gsm") — only one model per request is supported. For multi-model comparison, make one parallel tool call per model using the appropriate provider-specific tool.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`tilt`	No	Solar panel tilt in degrees (0 = flat, 90 = vertical); with `azimuth`, sets global_tilted_irradiance.
`daily`	No
`hourly`	No
`models`	No
`azimuth`	No	Solar panel azimuth in degrees (0 = south, -90 = east, 90 = west, ±180 = north); used with `tilt`.
`current`	No	Variables to return for the current time.
`end_date`	No	Date in YYYY-MM-DD format.
`end_hour`	No	Timestamp YYYY-MM-DDTHH:MM; hourly-precision alternative to start_date/end_date.
`latitude`	Yes
`timezone`	No	IANA time zone (e.g. "Europe/Paris"), or "auto" for the location's own. Default GMT.
`longitude`	Yes
`past_days`	No	Days before today to include, in addition to the forecast.
`past_hours`	No	Hours before now to include; alternative to `past_days`.
`start_date`	No	Date in YYYY-MM-DD format.
`start_hour`	No	Timestamp YYYY-MM-DDTHH:MM; hourly-precision alternative to start_date/end_date.
`timeformat`	No		iso8601
`minutely_15`	No	Variables to return at 15-minute resolution.
`forecast_days`	No	Days to forecast, starting today.
`cell_selection`	No	Grid cell to use near a coastline: prefer "land", prefer "sea", or the "nearest" cell.
`forecast_hours`	No	Hours to forecast; alternative to `forecast_days`.
`current_weather`	No	Legacy current-conditions summary; prefer `current`.
`wind_speed_unit`	No		kmh
`temperature_unit`	No		celsius
`precipitation_unit`	No		mm

Schema Changelog

Changes observed during successful MCP inspections.

Changed34 schema fields changedv2.5.0Sep 28, 2026

addedInput schema / $schema

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

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / azimuth

Added value: +{
+  "description": "Solar panel azimuth in degrees (0 = south, -90 = east, 90 = west, ±180 = north); used with `tilt`.",
+  "maximum": 180,
+  "minimum": -180,
+  "type": "number"
+}

addedInput schema / properties / cell_selection

Added value: +{
+  "description": "Grid cell to use near a coastline: prefer \"land\", prefer \"sea\", or the \"nearest\" cell.",
+  "enum": [
+    "land",
+    "sea",
+    "nearest"
+  ],
+  "type": "string"
+}

addedInput schema / properties / current

Added value: +{
+  "description": "Variables to return for the current time.",
+  "items": {
+    "anyOf": [
+      {
+        "enum": [
+          "temperature_2m",
+          "relative_humidity_2m",
+          "dewpoint_2m",
+          "dew_point_2m",
+          "apparent_temperature",
+          "precipitation_probability",
+          "precipitation",
+          "rain",
+          "showers",
+          "snowfall",
+          "snow_depth",
+          "weather_code",
+          "pressure_msl",
+          "surface_pressure",
+          "cloud_cover",
+          "cloud_cover_low",
+          "cloud_cover_mid",
+          "cloud_cover_high",
+          "visibility",
+          "evapotranspiration",
+          "et0_fao_evapotranspiration",
+          "vapour_pressure_deficit",
+          "wind_speed_10m",
+          "wind_speed_80m",
+          "wind_speed_120m",
+          "wind_speed_180m",
+          "wind_direction_10m",
+          "wind_direction_80m",
+          "wind_direction_120m",
+          "wind_direction_180m",
+          "wind_gusts_10m",
+          "temperature_80m",
+          "temperature_120m",
+          "temperature_180m",
+          "soil_temperature_0cm",
+          "soil_temperature_6cm",
+          "soil_temperature_18cm",
+          "soil_temperature_54cm",
+          "soil_moisture_0_to_1cm",
+          "soil_moisture_1_to_3cm",
+          "soil_moisture_3_to_9cm",
+          "soil_moisture_9_to_27cm",
+          "soil_moisture_27_to_81cm",
+          "uv_index",
+          "uv_index_clear_sky",
+          "is_day",
+          "sunshine_duration",
+          "wet_bulb_temperature_2m",
+          "total_column_integrated_water_vapour",
+          "cape",
+          "lifted_index",
+          "convective_inhibition",
+          "freezing_level_height",
+          "boundary_layer_height_pbl",
+          "shortwave_radiation",
+          "direct_radiation",
+          "diffuse_radiation",
+          "direct_normal_irradiance",
+          "global_tilted_irradiance",
+          "terrestrial_radiation",
+          "shortwave_radiation_instant",
+          "direct_radiation_instant",
+          "diffuse_radiation_instant",
+          "direct_normal_irradiance_instant",
+          "global_tilted_irradiance_instant",
+          "terrestrial_radiation_instant",
+          "wind_speed_200m",
+          "wind_direction_200m",
+          "snow_height",
+          "updraft",
+          "lightning_potential"
+        ],
+        "type": "string"
+      },
+      {
+        "description": "Pressure-level variable <variable>_<level>hPa, e.g. \"temperature_850hPa\".",
+        "pattern": "^(temperature|relative_humidity|cloud_cover|wind_speed|wind_direction|geopotential_height|vertical_velocity)_(30|50|70|100|150|200|250|300|400|500|600|700|800|850|900|925|950|975|1000)hPa$",
+        "type": "string"
+      }
+    ]
+  },
+  "type": "array"
+}

changedInput schema / properties / current_weather / description

Previous value: -"Include current weather conditions"New value: +"Legacy current-conditions summary; prefer `current`."

removedInput schema / properties / daily / description

Removed value: -"Daily weather variables to retrieve"

changedInput schema / properties / daily / items / enum

Previous value: -[
-  "temperature_2m_max",
-  "temperature_2m_min",
-  "apparent_temperature_max",
-  "apparent_temperature_min",
-  "precipitation_sum",
-  "weather_code",
-  "sunrise",
-  "sunset",
-  "wind_speed_10m_max",
-  "wind_gusts_10m_max",
-  "wind_direction_10m_dominant",
-  "shortwave_radiation_sum",
-  "uv_index_max"
-]New value: +[
+  "weather_code",
+  "temperature_2m_max",
+  "temperature_2m_min",
+  "apparent_temperature_max",
+  "apparent_temperature_min",
+  "sunrise",
+  "sunset",
+  "daylight_duration",
+  "sunshine_duration",
+  "uv_index_max",
+  "uv_index_clear_sky_max",
+  "rain_sum",
+  "showers_sum",
+  "snowfall_sum",
+  "precipitation_sum",
+  "precipitation_hours",
+  "precipitation_probability_max",
+  "wind_speed_10m_max",
+  "wind_gusts_10m_max",
+  "wind_direction_10m_dominant",
+  "shortwave_radiation_sum",
+  "et0_fao_evapotranspiration",
+  "temperature_2m_mean",
+  "apparent_temperature_mean",
+  "cape_mean",
+  "cape_max",
+  "cape_min",
+  "cloud_cover_mean",
+  "cloud_cover_max",
+  "cloud_cover_min",
+  "dewpoint_2m_mean",
+  "dewpoint_2m_max",
+  "dewpoint_2m_min",
+  "dew_point_2m_mean",
+  "dew_point_2m_max",
+  "dew_point_2m_min",
+  "et0_fao_evapotranspiration_sum",
+  "growing_degree_days_base_0_limit_50",
+  "leaf_wetness_probability_mean",
+  "leaf_wetness_probability_max",
+  "leaf_wetness_probability_min",
+  "precipitation_probability_mean",
+  "precipitation_probability_min",
+  "relative_humidity_2m_mean",
+  "relative_humidity_2m_max",
+  "relative_humidity_2m_min",
+  "snowfall_water_equivalent_sum",
+  "pressure_msl_mean",
+  "pressure_msl_max",
+  "pressure_msl_min",
+  "surface_pressure_mean",
+  "surface_pressure_max",
+  "surface_pressure_min",
+  "updraft_max",
+  "visibility_mean",
+  "visibility_max",
+  "visibility_min",
+  "wind_gusts_10m_mean",
+  "wind_gusts_10m_min",
+  "wind_speed_10m_mean",
+  "wind_speed_10m_min",
+  "wet_bulb_temperature_2m_mean",
+  "wet_bulb_temperature_2m_max",
+  "wet_bulb_temperature_2m_min",
+  "vapour_pressure_deficit_max"
+]

addedInput schema / properties / end_date

Added value: +{
+  "description": "Date in YYYY-MM-DD format.",
+  "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
+  "type": "string"
+}

addedInput schema / properties / end_hour

Added value: +{
+  "description": "Timestamp YYYY-MM-DDTHH:MM; hourly-precision alternative to start_date/end_date.",
+  "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}$",
+  "type": "string"
+}

removedInput schema / properties / forecast_days / default
```
Removed value: -7
```

changedInput schema / properties / forecast_days / description

Previous value: -"Number of forecast days"New value: +"Days to forecast, starting today."

addedInput schema / properties / forecast_hours

Added value: +{
+  "description": "Hours to forecast; alternative to `forecast_days`.",
+  "maximum": 9007199254740991,
+  "minimum": 0,
+  "type": "integer"
+}

removedInput schema / properties / hourly / description

Removed value: -"Hourly weather variables to retrieve"

addedInput schema / properties / hourly / items / anyOf

Added value: +[
+  {
+    "enum": [
+      "temperature_2m",
+      "relative_humidity_2m",
+      "dewpoint_2m",
+      "dew_point_2m",
+      "apparent_temperature",
+      "precipitation_probability",
+      "precipitation",
+      "rain",
+      "showers",
+      "snowfall",
+      "snow_depth",
+      "weather_code",
+      "pressure_msl",
+      "surface_pressure",
+      "cloud_cover",
+      "cloud_cover_low",
+      "cloud_cover_mid",
+      "cloud_cover_high",
+      "visibility",
+      "evapotranspiration",
+      "et0_fao_evapotranspiration",
+      "vapour_pressure_deficit",
+      "wind_speed_10m",
+      "wind_speed_80m",
+      "wind_speed_120m",
+      "wind_speed_180m",
+      "wind_direction_10m",
+      "wind_direction_80m",
+      "wind_direction_120m",
+      "wind_direction_180m",
+      "wind_gusts_10m",
+      "temperature_80m",
+      "temperature_120m",
+      "temperature_180m",
+      "soil_temperature_0cm",
+      "soil_temperature_6cm",
+      "soil_temperature_18cm",
+      "soil_temperature_54cm",
+      "soil_moisture_0_to_1cm",
+      "soil_moisture_1_to_3cm",
+      "soil_moisture_3_to_9cm",
+      "soil_moisture_9_to_27cm",
+      "soil_moisture_27_to_81cm",
+      "uv_index",
+      "uv_index_clear_sky",
+      "is_day",
+      "sunshine_duration",
+      "wet_bulb_temperature_2m",
+      "total_column_integrated_water_vapour",
+      "cape",
+      "lifted_index",
+      "convective_inhibition",
+      "freezing_level_height",
+      "boundary_layer_height_pbl",
+      "shortwave_radiation",
+      "direct_radiation",
+      "diffuse_radiation",
+      "direct_normal_irradiance",
+      "global_tilted_irradiance",
+      "terrestrial_radiation",
+      "shortwave_radiation_instant",
+      "direct_radiation_instant",
+      "diffuse_radiation_instant",
+      "direct_normal_irradiance_instant",
+      "global_tilted_irradiance_instant",
+      "terrestrial_radiation_instant",
+      "wind_speed_200m",
+      "wind_direction_200m",
+      "snow_height",
+      "updraft",
+      "lightning_potential"
+    ],
+    "type": "string"
+  },
+  {
+    "description": "Pressure-level variable <variable>_<level>hPa, e.g. \"temperature_850hPa\".",
+    "pattern": "^(temperature|relative_humidity|cloud_cover|wind_speed|wind_direction|geopotential_height|vertical_velocity)_(30|50|70|100|150|200|250|300|400|500|600|700|800|850|900|925|950|975|1000)hPa$",
+    "type": "string"
+  }
+]

removedInput schema / properties / hourly / items / enum

Removed value: -[
-  "temperature_2m",
-  "relative_humidity_2m",
-  "dewpoint_2m",
-  "apparent_temperature",
-  "pressure_msl",
-  "surface_pressure",
-  "cloud_cover",
-  "wind_speed_10m",
-  "wind_direction_10m",
-  "wind_gusts_10m",
-  "shortwave_radiation",
-  "precipitation",
-  "rain",
-  "snowfall",
-  "precipitation_probability",
-  "weather_code",
-  "visibility",
-  "uv_index"
-]

removedInput schema / properties / hourly / items / type
```
Removed value: -"string"
```
removedInput schema / properties / latitude / description
```
Removed value: -"Latitude in WGS84 coordinate system"
```
removedInput schema / properties / longitude / description
```
Removed value: -"Longitude in WGS84 coordinate system"
```

addedInput schema / properties / minutely_15

Added value: +{
+  "description": "Variables to return at 15-minute resolution.",
+  "items": {
+    "enum": [
+      "temperature_2m",
+      "relative_humidity_2m",
+      "dew_point_2m",
+      "apparent_temperature",
+      "precipitation",
+      "rain",
+      "snowfall",
+      "snowfall_height",
+      "freezing_level_height",
+      "sunshine_duration",
+      "weather_code",
+      "wind_speed_10m",
+      "wind_speed_80m",
+      "wind_speed_100m",
+      "wind_direction_10m",
+      "wind_direction_80m",
+      "wind_direction_100m",
+      "wind_gusts_10m",
+      "visibility",
+      "cape",
+      "lightning_potential",
+      "is_day"
+    ],
+    "type": "string"
+  },
+  "type": "array"
+}

addedInput schema / properties / models

Added value: +{
+  "enum": [
+    "jma_seamless",
+    "jma_msm",
+    "jma_msm_upper_level",
+    "jma_gsm"
+  ],
+  "type": "string"
+}

changedInput schema / properties / past_days / description

Previous value: -"Include past days data"New value: +"Days before today to include, in addition to the forecast."

removedInput schema / properties / past_days / enum
```
Removed value: -[
-  1,
-  2
-]
```
addedInput schema / properties / past_days / maximum
```
Added value: +92
```
addedInput schema / properties / past_days / minimum
```
Added value: +1
```

addedInput schema / properties / past_hours

Added value: +{
+  "description": "Hours before now to include; alternative to `past_days`.",
+  "maximum": 9007199254740991,
+  "minimum": 0,
+  "type": "integer"
+}

removedInput schema / properties / precipitation_unit / description
```
Removed value: -"Precipitation unit"
```

addedInput schema / properties / start_date

Added value: +{
+  "description": "Date in YYYY-MM-DD format.",
+  "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
+  "type": "string"
+}

addedInput schema / properties / start_hour

Added value: +{
+  "description": "Timestamp YYYY-MM-DDTHH:MM; hourly-precision alternative to start_date/end_date.",
+  "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}$",
+  "type": "string"
+}

removedInput schema / properties / temperature_unit / description
```
Removed value: -"Temperature unit"
```

addedInput schema / properties / tilt

Added value: +{
+  "description": "Solar panel tilt in degrees (0 = flat, 90 = vertical); with `azimuth`, sets global_tilted_irradiance.",
+  "maximum": 90,
+  "minimum": 0,
+  "type": "number"
+}

addedInput schema / properties / timeformat

Added value: +{
+  "default": "iso8601",
+  "enum": [
+    "iso8601",
+    "unixtime"
+  ],
+  "type": "string"
+}

changedInput schema / properties / timezone / description

Previous value: -"Timezone for timestamps (e.g., Europe/Paris, America/New_York)"New value: +"IANA time zone (e.g. \"Europe/Paris\"), or \"auto\" for the location's own. Default GMT."

removedInput schema / properties / wind_speed_unit / description
```
Removed value: -"Wind speed unit"
```

First observedv1.1.3Jan 31, 2026

TDQS

A4.3/5.0

Behavior4/5

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

Annotations already declare read-only, idempotent, open-world, and non-destructive. The description adds a key operational constraint beyond annotations: only one model per request is supported, and multi-model requires parallel calls. It doesn't discuss rate limits or data latency, but the core behavioral limit is disclosed.

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

Conciseness5/5

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

Three sentences, front-loaded with purpose and the critical constraint. No redundant or vague wording; every sentence earns its place.

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?

For a 24-parameter forecast tool with no output schema, the description covers the unique single-model constraint but omits crucial context: which JMA model variant to choose for a given use case, the regional coverage of JMA models, and default behaviors (e.g., timezone). The schema covers many parameters, but the description leaves important selection guidance to inference.

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

Parameters4/5

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

Schema description coverage is 63% (mid-range), and the description adds critical meaning for the `models` parameter: it must be a single JMA model (e.g., jma_msm, jma_gsm), which the schema's string type alone does not convey. It provides no additional semantics for the other 23 parameters, but the most important constraint is captured.

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

Purpose5/5

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

States a specific verb 'Get weather forecast' and resource 'JMA models', clearly identifying the provider. Distinguishes from sibling provider-specific forecasts by naming JMA and the models parameter, and routes multi-model comparison to provider-specific tools.

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

Usage Guidelines4/5

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

Explicitly instructs to specify exactly one model per request and how to handle multi-model comparison (one parallel call per model using the appropriate provider-specific tool). It doesn't state when to prefer JMA over other providers (e.g., geographic coverage), but the provider-specific context makes the intended use clear.

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

Deploy Server

JMA Forecast

Instructions

Input Schema

Schema Changelog

TDQS

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