# Relaystation Data Union

> Relaystation Data Union is a paid API for AI agents from api.relaystation.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Concatenates multiple tables into a single dataset using an ordered key-union schema, safely stacking rows from heterogeneous sources.

## Facts

- Endpoint: POST https://api.relaystation.ai/v1/data/union
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/relaystation-data-union-84c9b20b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6asNAxkpunmpfD33_rWF7

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 relaystation-data-union-84c9b20b -d '<json body>'
```

Example prompt: Stack my two sales datasets into one unified table — the Q1 results and Q2 results have slightly different columns, so use a key-union schema to safely merge them without losing any fields.

## When to prefer this

Choose this endpoint when you need to vertically stack or union multiple tabular datasets that may have different but overlapping column schemas, and you want the result to safely include all columns from all sources without data loss. It is particularly well-suited for ETL pipelines, report consolidation, and merging exports from heterogeneous systems where schema normalization is needed automatically.

## Known failure modes

- Mismatched key types across tables causing schema resolution failure
- Input tables too large for per-call MB budget, requiring chunking
- Malformed input table format (unsupported serialization format)
- Empty or null table inputs returning an empty result or error
- Column name collisions with conflicting data types across sources

## How this service works

$0.0002/MB. Concatenate tables with an ordered key-union schema — stack datasets safely. 1¢ x402 min; remainder auto-credits — relaystation.ai/penny

## Output

Returns a single unified table whose schema is the ordered key-union of all input tables' columns, with rows from all inputs stacked in order and missing column values filled with nulls where a source table lacked that column. Billed at $0.0002/MB with a 1¢ minimum; any remainder is auto-credited.

## 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": {
     "properties": {}
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST",
      "PUT",
      "PATCH"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/relaystation-data-union-84c9b20b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relaystation.ai](https://www.zero.xyz/host/api.relaystation.ai/llms.txt)