Sun Position Grounding Data for AI Agents
The tool
Ground agents in verifiable solar altitude and azimuth data so daylight and siting answers rest on real astronomy, not estimates.
Once your client is connected to the VerveContext MCP server, this appears in its tool list as SunPositionGroundingDataforAIAgents. It is read-only and open-world: it fetches, it never mutates anything on your side, so most clients will call it without asking you to confirm.
{
"name": "SunPositionGroundingDataforAIAgents",
"arguments": {
"lat": "37.7749",
"lon": "-122.4194"
}
}What that looks like in a conversation
You don't name the tool — the model picks it. Asking about 37.7749 in the terms this source covers is enough for it to reach for SunPositionGroundingDataforAIAgents on its own.
Connecting
One server URL covers every source in the catalog, including this one. Authorization is OAuth — the client opens a browser once and there is no key to paste into a config file.
{
"mcpServers": {
"vervecontext": {
"url": "https://api.vervecontext.com/v1/mcp"
}
}
}https://api.vervecontext.com/v1/mcpPer-client setup — Claude Desktop, Cursor, VS Code, ChatGPT — is on the MCP setup page.
Arguments
These are the properties on the tool's inputSchema, so a well-behaved client validates them before the call is made.
| Argument | Type | Example | Description |
|---|---|---|---|
latRequired | number | 37.7749 | The latitude of the location |
lonRequired | number | -122.4194 | The longitude of the location |
datePremium | string | 01-16-2026 | The date to get the sun position data for (MM-DD-YYYY) |
time | string | 14:30 | The time of day for the calculation (HH:mm format, 24-hour), read in the timezone of the coordinates. Defaults to 00:00 if not provided |
timezone | string | America/Los_Angeles | IANA timezone to read the date and time in, such as America/Los_Angeles. Defaults to the timezone of the coordinates |
What the model gets back
The result carries a structuredContent object matching the tool's declared outputSchema, so a client can read fields without parsing prose. status is "ok" on success and error is null; a null field means the value wasn't available for that input, not that the call failed.
{
"status": "ok",
"error": null,
"data": {
"date": "01-16-2026",
"time": "14:30",
"timezone": "America/Los_Angeles",
"timestampUTC": "2026-01-16T22:30:00.000Z",
"coordinates": {
"latitude": 37.7749,
"longitude": -122.4194
},
"sun": {
"altitude": 0.41616137328975444,
"azimuth": 0.5817558808515568,
"altitudeDegrees": 23.844,
"azimuthDegrees": 33.332,
"compassBearing": 213.332,
"isDaylight": true,
"declination": -20.7961,
"rightAscension": 19.9228,
"hourAngle": 2.174,
"distance": 0.983786
},
"equationOfTime": -9.88,
"airMass": 2.454,
"clearSky": {
"directNormal": 702.4,
"globalHorizontal": 284.9
},
"shadowRatio": 2.254,
"panelAim": {
"tilt": 66.07,
"azimuth": 213.44
}
}
}Fields
| Field | Type | Example | Description |
|---|---|---|---|
date | string | Date the position was calculated for | |
time | string | Time of day the position was calculated for | |
timezone | string | IANA timezone the date and time were read in, resolved from the coordinates unless one was given | |
timestampUTC | string | The instant the position was calculated for, in UTC, so the answer is unambiguous | |
coordinates | object | The point on Earth the position was calculated from | |
└ coordinates.latitude | number | Latitude used for the calculation | |
└ coordinates.longitude | number | Longitude used for the calculation | |
sun | object | Where the sun sits in the sky at that time and place | |
└ sun.altitude | number | Height of the sun above the horizon, in radians; negative when the sun is below the horizon. Multiply by 180/PI for degrees | |
└ sun.azimuth | number | Direction of the sun, in radians measured from due south and increasing westward. Multiply by 180/PI for degrees, then add 180 for a compass bearing | |
└ sun.altitudeDegrees | number | Height of the sun above the horizon in degrees; negative when below | |
└ sun.azimuthDegrees | number | Direction of the sun in degrees from due south, increasing westward | |
└ sun.compassBearing | number | Direction of the sun as a compass bearing, 0 for north and 180 for south | |
└ sun.isDaylight | boolean | Whether the sun is above the horizon at this time and place | |
└ sun.declinationPremium | number | Angle of the sun north or south of the celestial equator, in degrees | |
└ sun.rightAscensionPremium | number | Position of the sun along the celestial equator, in hours | |
└ sun.hourAnglePremium | number | Hours since the sun crossed the local meridian; negative before solar noon | |
└ sun.distancePremium | number | Distance from Earth to the sun in astronomical units | |
equationOfTimePremium | number | Minutes a sundial reads ahead of the clock at this date; negative when it reads behind | |
airMassPremium | number | How much atmosphere the sunlight crosses, as a multiple of straight overhead; null after dark | |
clearSkyPremium | object | Cloudless-sky irradiance estimate in watts per square metre; null after dark | |
└ clearSky.directNormalPremium | number | Irradiance on a surface aimed straight at the sun, which is what a tracker sees | |
└ clearSky.globalHorizontalPremium | number | Irradiance on a flat horizontal surface | |
shadowRatioPremium | number | Length of the shadow cast by an object, per unit of its height; null after dark | |
panelAimPremium | object | Where to point a solar panel to face the sun squarely at this moment; null after dark | |
└ panelAim.tiltPremium | number | Degrees to tilt the panel back from vertical | |
└ panelAim.azimuthPremium | number | Compass bearing to point the panel at |
Why ground on it
A model can produce something that looks like this answer from its training data, and be confidently out of date or simply wrong. This source returns the current value with a shape you can check, which is the difference between an answer you can cite and one you have to hedge.
Point an evaluation at timestampUTC: it is the field most worth pinning a claim to, and it is either present and current or absent — never plausibly invented.
Failure modes
Errors come back as tool errors with a sentence the model can act on, not a bare status code.
| Status | What it means |
|---|---|
400 / 422 | The arguments didn't validate. The message names the offending one. |
401 | The OAuth session is invalid or expired — reconnect the server. |
403 | Out of credits. Not a bad key — the month's allowance is spent. |
404 | This source isn't part of VerveContext. Check the catalog. |
429 | Brief rate limit. Retrying after a moment succeeds. |
Other ways to use Sun Position Grounding Data for AI Agents
Set up Sun Position Grounding Data for AI Agents on VerveContext, or reach the same source a different way. Your VerveContext account and credits work on all of them — one key, one balance.
Frequently asked questions
Do I have to tell the agent to use SunPositionGroundingDataforAIAgents?
No. The tool's name and description are in the model's context once the server is connected, so it selects the tool when the question calls for it. Naming it explicitly works too and is useful when you want to force the call.
Does connecting the server expose every tool at once?
Yes — one connection lists the whole VerveContext catalog. Clients with a tool budget can usually filter the list; the credit cost is per call, so an unused tool costs nothing.
What does a call cost?
1 credit each time the tool actually runs. A model that reasons about the tool without calling it costs nothing.
Is there a REST version of this?
Yes — the same source is available as a plain HTTPS endpoint on APIVerve, linked above. Same data, same credits, same account.