# FRED 30-Year Fixed Mortgage Rate Change Monitor

> FRED 30-Year Fixed Mortgage Rate Change Monitor is a paid API for AI agents from oracles-production.up.railway.app, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-14).

Returns newly detected FRED observations of the 30-year fixed mortgage rate, with value, date, and significance score, filtered by recency and importance.

## Facts

- Endpoint: GET https://oracles-production.up.railway.app/v1/econ-mortgage/changes
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fred-30-year-fixed-mortgage-rate-change-monitor-4c6f7414
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZFzqGNwmliV7hKBfBwfdW

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 fred-30-year-fixed-mortgage-rate-change-monitor-4c6f7414
```

Example prompt: Show me any new 30-year fixed mortgage rate changes detected since January 1, 2025, but only ones with a significance score of at least 5 — limit it to 20 results.

## When to prefer this

Use this endpoint when you need machine-readable, significance-scored change events for the 30-year fixed mortgage rate sourced from FRED, especially when you want to filter by recency or importance threshold. Prefer over raw FRED API calls when you need pre-processed change detection with scoring rather than raw time series data.

## Known failure modes

- FRED_API_KEY not configured — endpoint no-ops and returns empty or error response
- since parameter not ISO-8601 formatted — validation error
- limit out of range (must be 1-500) — 400 bad request
- min_significance out of range (must be 1-10) — 400 bad request
- FRED upstream unavailable — may return stale or empty results
- Payment of 0.05 USDC not provided — 402 Payment Required

## How this service works

New data prints of 30-year fixed mortgage rate since a timestamp (US Federal Reserve / FRED), with each % value and its observation date. Answers "did 30-year fixed mortgage rate change, and to what?"

## Output

A JSON object containing a count of changes, the source identifier, and an array of change objects each with a type, title, detail, summary, entityId, sourceUrl, detectedAt timestamp, significance score (1-10), and effectiveDate.

## 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",
     "properties": {
      "limit": {
       "type": "integer",
       "maximum": 500,
       "minimum": 1
      },
      "since": {
       "type": "string",
       "format": "date-time",
       "description": "Only changes detected after this ISO-8601 instant"
      },
      "min_significance": {
       "type": "integer",
       "maximum": 10,
       "minimum": 1,
       "description": "Keep only changes scored at least this"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "count": {
       "type": "integer"
      },
      "source": {
       "type": "string"
      },
      "changes": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "type": {
          "type": "string"
         },
         "title": {
          "type": "string"
         },
         "detail": {
          "type": "object"
         },
         "summary": {
          "type": "string"
         },
         "entityId": {
          "type": "string"
         },
         "sourceUrl": {
          "type": [
           "string",
           "null"
          ],
          "description": "Primary-source link for verification"
         },
         "detectedAt": {
          "type": "string",
          "format": "date-time"
         },
         "significance": {
          "type": "integer",
          "maximum": 10,
          "minimum": 1
         },
         "effectiveDate": {
          "type": [
           "string",
           "null"
          ]
         }
        }
       }
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fred-30-year-fixed-mortgage-rate-change-monitor-4c6f7414/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from oracles-production.up.railway.app](https://www.zero.xyz/host/oracles-production.up.railway.app/llms.txt)