# JSON Lines Stringify

> JSON Lines Stringify is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Serializes an array of JSON objects into compact newline-delimited JSON Lines (JSONL) format with counts and a versioned result contract

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/json-lines-stringify?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/json-lines-stringify-4dd537cc
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KU4AaLO1jBEGs-kl0Eg6z

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 json-lines-stringify-4dd537cc -d '<json body>'
```

Example prompt: Take these structured records and serialize them as compact JSON Lines — one JSON object per line — so I can hand the result off to a downstream tool that only accepts JSONL format.

## When to prefer this

Choose this endpoint when an agent needs a deterministic, bounded, stateless JSONL serialization with a versioned result contract and line-count metadata — particularly before handing structured data to a downstream tool that enforces a strict JSONL input contract. Prefer over ad-hoc client-side serialization when auditability, count verification, or a standardized result envelope matters.

## Known failure modes

- Input array exceeds 256 items — request rejected with a bounds error
- Individual objects exceed 128 properties — validation error returned
- Malformed or non-serializable input values cause serialization failure
- Empty items array returns zero-line output with count of 0
- Network or payment processing failure returns 402 or 5xx error

## How this service works

JSON Lines Stringify: JSON Lines Stringify serializes bounded JSON values as compact newline-delimited JSON from bounded caller-supplied values without an external provider. Call JSON Lines Stringify before an agent hands structured data or a batch plan to a downstream tool with a stricter contract. Returns the bounded transformation or validation finding with counts, normalized values, and a versioned result contract for JSON Lines Stringify as versioned deterministic JSON. Price: $0.001 USDC…

## Output

Returns a versioned deterministic JSON result containing the JSONL-formatted string (each input object serialized on its own line), a count of lines produced, normalized values, and a versioned result contract identifier. No data is retained after processing.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "items": {
   "type": "array",
   "items": {
    "type": "object",
    "maxProperties": 128,
    "additionalProperties": true
   },
   "maxItems": 256,
   "description": "Items supplied to JSON Lines Stringify; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "text": "{\"id\":1}\n{\"id\":2}",
   "line_count": 2
  },
  "schema": "delx/util-json-lines-stringify/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "0e0bc9cb6b5f1b41ed89071cc8222f2bbc6b2c97af66c03cd0d24ac5102d86af",
   "external_calls": 0
  },
  "operation": "data_batch:json_lines_stringify"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/json-lines-stringify-4dd537cc/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)