# Plonk Circuit Builder MCP

> Plonk Circuit Builder MCP is a paid API for AI agents from api.m2mcent.com, paid per call via x402, $0.4/call, status unknown (last checked 2026-10-12).

Builds and processes PLONK zero-knowledge proof circuits from input data

## Facts

- Endpoint: POST https://api.m2mcent.com/plonk-circuit-builder-mcp/api/process?utm_source=zero.xyz
- Price: $0.4/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/plonk-circuit-builder-mcp-e7c44526
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HQZ9TGfHA7zDiigDrqfTD

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 plonk-circuit-builder-mcp-e7c44526 -d '<json body>'
```

Example prompt: Can you build me a PLONK zero-knowledge circuit for my constraint data: 'x * y = z where x and y are private inputs and z is public'?

## When to prefer this

Choose this endpoint when you need to programmatically build or compile PLONK-based zero-knowledge proof circuits as part of a cryptographic workflow, zkRollup pipeline, or privacy-preserving application. Prefer it over general ZK tooling when you need a hosted, pay-per-use PLONK circuit builder that integrates directly into an agentic workflow without local toolchain setup.

## Known failure modes

- Invalid or malformed circuit data string returns a parsing or validation error
- Unsupported constraint types may cause compilation failure
- Malformed JSON input results in 400-level error
- Payment failure or insufficient USDC balance blocks the call via x402
- Overly complex circuits may exceed processing limits or time out

## How this service works

The premier global index of 1,069 monetized MCP nodes across 205 specialized subdomains. Gasless USDC runtime settlements via x402 V2 Spec on Base L2. Save 95% token context.

## Output

Returns a compiled PLONK circuit artifact, which may include the constraint system, proving key, verification key, and any circuit-specific metadata needed to generate or verify zero-knowledge proofs.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/plonk-circuit-builder-mcp-e7c44526/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.m2mcent.com](https://www.zero.xyz/host/api.m2mcent.com/llms.txt)