# Moon Phase Lookup

> Moon Phase Lookup is a paid API for AI agents from astro.openverbs.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-14).

Returns the moon phase for a given calendar date and UTC time

## Facts

- Endpoint: POST https://astro.openverbs.com/v1/moon-phase
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/moon-phase-lookup-0b2ad1da
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aoNPrhdg22XjwomoPcXhw

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability moon-phase-lookup-0b2ad1da -d '<json body>'
```

Example prompt: What is the moon phase on July 4, 2025 at 9pm UTC?

## When to prefer this

Choose this endpoint when you need a precise, programmatic lookup of the moon phase for any historical or future date, especially when you need a specific UTC time component alongside the date. Prefer this over general almanac queries when integrating lunar phase data into an automated workflow, event planner, or astrology application.

## Known failure modes

- Missing required fields (year, month, day) returns a validation error
- Day value out of range for the given month may return an error or unexpected result
- Year outside 1–9999 range returns a validation error
- Invalid month value (outside 1–12) returns a validation error
- Network timeout or service unavailability returns a 5xx error
- Hour or minute out of valid range returns a validation error

## How this service works

Compute the Moon's phase name, age in days since the last new moon and illuminated fraction (0..1) for a UTC date/time. Uses the mean synodic month (29.53 days).

## Output

Returns the moon phase for the specified date and time, including the phase name (e.g., new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, waning crescent), phase angle or illumination percentage, and other relevant lunar cycle details.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "year",
      "month",
      "day"
     ],
     "properties": {
      "day": {
       "type": "integer",
       "maximum": 31,
       "minimum": 1
      },
      "hour": {
       "type": "integer",
       "maximum": 23,
       "minimum": 0,
       "description": "UTC hour. Default 12."
      },
      "year": {
       "type": "integer",
       "maximum": 9999,
       "minimum": 1
      },
      "month": {
       "type": "integer",
       "maximum": 12,
       "minimum": 1
      },
      "minute": {
       "type": "integer",
       "maximum": 59,
       "minimum": 0,
       "description": "Default 0."
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/moon-phase-lookup-0b2ad1da/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from astro.openverbs.com](https://www.zero.xyz/host/astro.openverbs.com/llms.txt)