# Deterministic A2A Broken-JSON Repair & Schema Validator

> Deterministic A2A Broken-JSON Repair & Schema Validator is a paid API for AI agents from prompt-guard.agentdiet.dev, paid per call via MPP, $0.002/call, status unknown (last checked 2026-10-21).

Repairs malformed, truncated, or markdown-wrapped LLM JSON outputs (trailing commas, single quotes, markdown fences) so multi-agent pipelines stay stable

## Facts

- Endpoint: GET https://prompt-guard.agentdiet.dev/v1/json-validator?utm_source=zero.xyz
- Price: $0.002/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: prompt-guard.agentdiet.dev
- Website: https://prompt-guard.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/prompt-guard-agentdiet-dev-deterministic-a2a-broken-json-repair-e8e3a23e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ElFrE94S64vQ4l6tJG2Uj

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 prompt-guard-agentdiet-dev-deterministic-a2a-broken-json-repair-e8e3a23e
```

Example prompt: Fix this broken JSON from my LLM — it has trailing commas and markdown backtick fences wrapping it: ```{"name": "Alice", "age": 30,}```

## When to prefer this

Use this endpoint when you need deterministic, rule-based JSON repair in a multi-agent pipeline — particularly when LLM outputs contain predictable syntax errors like trailing commas, markdown fences, or single quotes. Prefer this over custom parsing code when you want a reliable, paid microservice that handles these common LLM output artifacts without hallucinating or guessing at content.

## Known failure modes

- Input is so severely malformed that deterministic repair is impossible — returns error indicating unrecoverable structure
- Input string is empty or missing (minLength:1 violated) — returns validation error
- JSON is ambiguous after truncation and cannot be completed deterministically — may return partial result or error
- Network timeout or service unavailability — returns HTTP 5xx
- Payment not completed via x402 protocol — returns HTTP 402 requiring payment

## How this service works

Repairs truncated or malformed LLM JSON outputs (trailing commas, markdown fences, single quotes) so multi-agent pipelines never crash. (Live x402 v2, IETF MPP & MCP endpoint at https://prompt-guard.agentdiet.dev/v1/json-validator)

## Output

A repaired, valid JSON object derived from the malformed input string, with syntax errors corrected — trailing commas removed, markdown fences stripped, single quotes converted to double quotes, and truncated structures completed where possible.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "raw_json"
 ],
 "properties": {
  "raw_json": {
   "type": "string",
   "minLength": 1,
   "description": "Malformed, truncated, or markdown-wrapped JSON string to deterministically repair"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/prompt-guard-agentdiet-dev-deterministic-a2a-broken-json-repair-e8e3a23e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from prompt-guard.agentdiet.dev](https://www.zero.xyz/host/prompt-guard.agentdiet.dev/llms.txt)