# Calendar Systems Moon Calendar

> Calendar Systems Moon Calendar is a paid API for AI agents from calendar-systems.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Returns all lunar phase events (new moon, first quarter, full moon, last quarter) for a given month in UTC, with exact times and a blue-moon flag.

## Facts

- Endpoint: GET https://calendar-systems.x402tookit.com/moon-calendar?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/calendar-systems-moon-calendar-9a55ae8f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_w4-WF_UH4r25u7SIxlthN

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 calendar-systems-moon-calendar-9a55ae8f
```

Example prompt: What are all the moon phases for March 2025, and is there a blue moon that month? I need the exact UTC times for each new moon, first quarter, full moon, and last quarter.

## When to prefer this

Use this endpoint when you need a complete list of all lunar phase events for a specific calendar month, especially when you need exact UTC times or need to detect blue moons. Prefer this over a single-phase lookup when you want the full monthly lunar picture rather than just the current or next phase.

## Known failure modes

- Month parameter outside 1900–2100 range returns an error
- Malformed month string (not YYYY-MM) causes validation failure
- Degraded flag set to true if data source is partially unavailable
- Missing required 'month' query parameter results in a bad-request error

## How this service works

All new moons, first quarters, full moons and last quarters in a month (UTC) with times and a blue-moon flag.

## Output

Returns a structured object containing arrays of UTC datetime strings for new moons, first quarters, full moons, and last quarters within the specified month, along with counts, a boolean blue-moon flag, a summary, the source, and optional disclaimer or degraded-service indicators.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "month"
     ],
     "properties": {
      "month": {
       "type": "string",
       "description": "YYYY-MM, 1900 to 2100"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "month": {
       "type": [
        "null",
        "string"
       ]
      },
      "events": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "object",
        "properties": {
         "utc": {
          "type": [
           "null",
           "string"
          ]
         },
         "phase": {
          "type": [
           "null",
           "string"
          ]
         }
        }
       }
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "blueMoon": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "newMoons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "fullMoons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "newMoonCount": {
       "type": [

… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/calendar-systems-moon-calendar-9a55ae8f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from calendar-systems.x402tookit.com](https://www.zero.xyz/host/calendar-systems.x402tookit.com/llms.txt)