# FastX402 JSON Merge Patch

> FastX402 JSON Merge Patch is a paid API for AI agents from fastx402.tools, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-23).

Applies an RFC 7386 JSON Merge Patch document to a target JSON object, returning the merged result

## Facts

- Endpoint: GET https://fastx402.tools/json-merge-patch?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastx402-json-merge-patch-eef2d165
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_0-PGwjgqYpOo6AHc-EfSN

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 fastx402-json-merge-patch-eef2d165
```

Example prompt: Apply this JSON merge patch — {"age": 31, "address": {"city": "NYC", "zip": "10002"}, "active": true} — to my base document {"name": "Alice", "age": 28, "address": {"city": "Boston"}, "active": false} and give me the merged result.

## When to prefer this

Choose this endpoint when you need a lightweight, stateless, pay-per-call RFC 7386 JSON Merge Patch operation with no account or API key setup. Ideal for agents that need to merge or partially update JSON objects on the fly without spinning up a local library or language runtime. Prefer over full JSON Patch (RFC 6902) when your update logic is simple field-level overrides or deletions rather than complex array operations.

## Known failure modes

- Invalid JSON in target or patch query parameters returns an error
- Malformed RFC 7386 patch structure may produce unexpected output or error
- Missing required 'target' or 'patch' query parameters returns a validation error
- Payment failure or insufficient USDC balance blocks the request
- Network timeout if the service is temporarily unavailable

## How this service works

200 pay-per-call tools for AI agents, from $0.001 per request in USDC on Base or Solana with x402. No account, no API key.

## Output

A JSON object containing a 'result' key whose value is the fully merged JSON document after applying the RFC 7386 merge patch to the target — with patched fields updated, null-patched fields removed, and unpatched fields preserved.

## 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": [
      "target",
      "patch"
     ],
     "properties": {
      "patch": {
       "type": "string",
       "description": "The RFC 7386 JSON Merge Patch to apply"
      },
      "target": {
       "type": "string",
       "description": "The original JSON document to be patched"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "result": {
       "type": "object",
       "properties": {
        "age": {
         "type": "integer"
        },
        "name": {
         "type": "string"
        },
        "active": {
         "type": "boolean"
        },
        "address": {
         "type": "object",
         "properties": {
          "zip": {
           "type": "string"
          },
          "city": {
           "type": "string"
          }
         }
        }
       }
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "age": 31,
   "name": "Alice",
   "active": true,
   "address": {
    "zip": "10002",
    "city": "NYC"
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastx402-json-merge-patch-eef2d165/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fastx402.tools](https://www.zero.xyz/host/fastx402.tools/llms.txt)