# x402-agent-suite MPP Session Create/Retrieve

> x402-agent-suite MPP Session Create/Retrieve is a paid API for AI agents from x402-agent-suite-production.up.railway.app, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-02).

Creates or retrieves a Multi-Payment Protocol (MPP) session on Base or Solana after x402 micropayment, returning session state, settlement info, and next steps.

## Facts

- Endpoint: POST https://x402-agent-suite-production.up.railway.app/api/mpp/session?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-agent-suite-mpp-session-create-retrieve-e84a1661
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bgGWmlUAztLwMhvYDJb-v

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 x402-agent-suite-mpp-session-create-retrieve-e84a1661 -d '<json body>'
```

Example prompt: Start an MPP session for my agent on Base using x402 — I expect around 50 calls at roughly $0.03 USDC each, and I need the session ID and settlement details so I can track usage.

## When to prefer this

Use this endpoint when an AI agent needs to establish or resume a metered MPP session backed by x402 micropayments on Base or Solana, especially when you need session-level tracking of API call consumption, per-call USDC pricing, and settlement status. Prefer this over direct per-call payment when amortizing costs across many calls or when you need facilitator-backed session management.

## Known failure modes

- Payment not received or insufficient — session not created, 402 response
- Invalid HTTP method (only GET/HEAD/DELETE accepted for input.method) — validation error
- Unsupported chain — session creation fails with chain error
- Session not found on retrieval — returns not-found or empty session
- Network timeout to Base/Solana RPC — settlement status unavailable

## How this service works

Creates or retrieves an MPP session after payment on Base or Solana.

## Output

Returns a JSON object with ok/success flags, a session object (sessionId, status, chain, agentId, expectedCalls, callsUsed, avgPricePerCallUsdc), settlement details (network, callsSettled, plannedCalls, estimatedTotalUsdc, facilitatorUrl), facilitator info with MPP docs link, a confidence score, list of checks passed, a recommendation string, a savings note, and next steps as a string array.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {}
 }
}
```

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "ok",
      "status",
      "success",
      "action",
      "session",
      "settlement",
      "recommendation",
      "facilitator",
      "nextSteps",
      "savingsNote",
      "confidence",
      "checks_passed"
     ],
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "action": {
       "type": "string"
      },
      "status": {
       "type": "string"
      },
      "session": {
       "type": "object",
       "required": [
        "sessionId",
        "status",
        "chain",
        "agentId",
        "expectedCalls",
        "callsUsed",
        "avgPricePerCallUsdc"
       ],
       "properties": {
        "chain": {
         "type": "string"
        },
        "status": {
         "type": "string"
        },
        "agentId": {
         "type": "string"
        },
        "callsUsed": {
         "type": "number"
        },
        "sessionId": {
         "type": "string"
        },
        "expectedCalls": {
         "type": "number"
        },
        "avgPricePerCallUsdc": {
         "type": "number"
        }
       }
      },
      "success": {
       "type": "boolean"
      },
      "nextSteps": {
       "type": "array",
       "items": {
        "type": "string"
       }
      },
      "confidence": {
       "type": "number"
      },
      "settlement": {
       "type": "object",
       "required": [
        "status",
        "sessionId",
        "network",
        "chain",
        "agentId",
        "callsSettled",
        "plannedCalls",
        "estimatedTotalUsdc",
        "facilitatorUrl"
       ],
       "properties": {
        "chain": {
         "type": "string"
        },
        "status": {
         "type": "string"
        },
        "agentId": {
         "type": "string"
        },
        "netw
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "session": {
   "status": "open",
   "sessionId": "mpp_example"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-agent-suite-mpp-session-create-retrieve-e84a1661/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-agent-suite-production.up.railway.app](https://www.zero.xyz/host/x402-agent-suite-production.up.railway.app/llms.txt)