# io.github.stevemilton/x402-payagent-mcp (npm · @arispay/payagent-mcp)

Pay x402 APIs in USDC on Base, Solana, and BNB Chain with spend mandates, receipts, idempotency.

- Trust score: 83/100 (high trust)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-25

## Components

- npm · `@arispay/payagent-mcp`: 83/100 (this document), [markdown](https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp.md), [page](https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp)

## Channel facts

- Registry: `npm`
- Package: `@arispay/payagent-mcp`
- Version: `4.1.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-09-25.

- **Supply Chain Security**: 98/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - 33 of 107 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 28 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 74/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1209 tokens (~172/item across 7 items; 7 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 97/100
  - Stability observed for 29 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 94/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 83% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.
  - An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the io.github.stevemilton/x402-payagent-mcp server?

io.github.stevemilton/x402-payagent-mcp runs locally as an npm package, launched with npx -y @arispay/payagent-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add stevemilton-x402-payagent-mcp -- npx -y @arispay/payagent-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "stevemilton-x402-payagent-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@arispay/payagent-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "stevemilton-x402-payagent-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@arispay/payagent-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add stevemilton-x402-payagent-mcp -- npx -y @arispay/payagent-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "stevemilton-x402-payagent-mcp": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "@arispay/payagent-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add stevemilton-x402-payagent-mcp --command npx --arg -y --arg @arispay/payagent-mcp
```

### Hermes

```yaml
mcp_servers:
  stevemilton-x402-payagent-mcp:
    command: "npx"
    args: ["-y", "@arispay/payagent-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "stevemilton-x402-payagent-mcp": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "@arispay/payagent-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add stevemilton-x402-payagent-mcp -t stdio -c npx -a -y @arispay/payagent-mcp
```

### Other

```json
{
  "mcpServers": {
    "stevemilton-x402-payagent-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@arispay/payagent-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-25 (score 83, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-09-24 (score 83, 0)

- [security] Stability: 0.97 → pass

### 2026-09-23 (score 83, +1)

No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-21 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-19 (score 81, +1)

No change was recorded against any check on this day. Stability & Change Management went from 80 to 83. That category is still filling its 30-day observation window: 24 days of observed history at the previous scan, 25 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-17 (score 80, +1)

No change was recorded against any check on this day. Stability & Change Management went from 73 to 77. That category is still filling its 30-day observation window: 22 days of observed history at the previous scan, 23 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-14 (score 79, +1)

No change was recorded against any check on this day. Stability & Change Management went from 63 to 67. That category is still filling its 30-day observation window: 19 days of observed history at the previous scan, 20 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-09-12 (score 78, +1)

No change was recorded against any check on this day. Stability & Change Management went from 57 to 60. That category is still filling its 30-day observation window: 17 days of observed history at the previous scan, 18 at this one. The score rises as the window fills, whether or not the server changes.

## MCP tools (7)

### `setup` (~158 tokens)

Creates or recovers an ArisPay account for delegated custody and provisions a USDC payer wallet in one call (side effects: registers the email, creates a Coinbase CDP-managed wallet, writes credentials to ~/.payagent/config.json on this machine). Moves no money — it does NOT spend funds. Idempotent: re-running with the same email recovers the existing account and its wallets. Not needed in self-custody mode: if PAYAGENT_PRIVATE_KEY is set, skip setup entirely — pay works with the local key alone.

Input parameters:

- `email` (string, required): Email to register the account under. It is also the recovery key — use a real address.
- `name` (string): Human name. Falls back to the email local-part.

### `discover` (~172 tokens)

Searches the ArisPay marketplace for paid APIs by capability or plain-language intent, optionally budget-bounded (integer cents). Read-only — spends no money, needs no API key. Returns ranked candidates with endpoint URL, price in cents, health and verification flags. Select this to FIND an endpoint; then inspect to price a specific URL, then pay to call it.

Input parameters:

- `budgetCentsMax` (integer): Maximum acceptable price in INTEGER CENTS (500 = $5.00). Free listings always pass.
- `category` (string): Optional category filter (inference, data, media, search, social, infrastructure, trading, other).
- `limit` (integer): Max results (default 5, max 20).
- `query` (string, required): Capability or plain-language intent, e.g. 'flight search'.

### `inspect` (~87 tokens)

Fetches an x402-protected URL WITHOUT paying and reports its price, asset, network, and payment requirements. Read-only — spends no money, sends no payment header, needs no API key or account. Always safe. Select this before pay to know exactly what a resource costs.

Input parameters:

- `url` (string, required): The URL to inspect. Expected to return HTTP 402 with an x402 challenge.

### `pay` (~291 tokens)

SPENDS REAL MONEY — on-chain and irreversible. The complete machine payment path: makes the HTTP request, and if the server answers 402, selects the supported asset/network variant (USDC on Base/Ethereum/Polygon; delegated mode also settles Solana and BNB Chain variants), validates policy, pays, retries the request, and returns the response plus a structured machine-readable receipt. Requires an idempotencyKey: re-calling with a key that already paid returns the cached receipt and does NOT pay again. Mode selection: PAYAGENT_PRIVATE_KEY set → signs locally (self-custody; wallet balance is the only cap); otherwise pays through the stored ArisPay agent whose per-tx/daily/monthly mandate is enforced server-side BEFORE signing. Use inspect first to see the price. Do not use for ordinary unpaid HTTP requests.

Input parameters:

- `agent` (string): Optional name of a stored x402 payer agent (delegated mode).
- `body` (string)
- `headers` (object)
- `idempotencyKey` (string, required): Caller-chosen unique key for this payment intent (min 8 chars, e.g. a UUID). Re-calling with a key that already paid returns the cached receipt WITHOUT paying again. Use a fresh key for each new paym…
- `method` (string)
- `url` (string, required): The full URL of the API endpoint to call.

### `balance` (~111 tokens)

Read-only: shows the active payment identity — the stored ArisPay agent (delegated) or the PAYAGENT_PRIVATE_KEY-derived address (self-custody) — with its USDC deposit address, on-chain balance, and (delegated) spend-mandate limits. Spends no money, never pays. Select this to find where to send USDC, to confirm a deposit landed, or when a payment fails.

Input parameters:

- `agent` (string): Optional name of a locally-stored x402 agent.

### `history` (~102 tokens)

Read-only: lists recent payments — the server-side activity feed in delegated mode (newest first), or locally recorded receipts in self-custody mode. Spends no money. Select this to reconcile what was paid, retrieve a past receipt, or audit an agent's spending.

Input parameters:

- `agent` (string): Optional stored agent name — limits the feed to that wallet (delegated mode).
- `limit` (integer): Max entries (default 10, max 50).

### `check_payment_signal` (~288 tokens)

SPENDS REAL MONEY — 1¢ (USDC, Base mainnet) per UNCACHED call; a still-valid cached artifact returns WITHOUT spending, and an unknown resource is answered free. Buys ArisPay Signal: recent signed probe evidence about an x402 resource (did a real paid probe settle and deliver?) as an arispay.signal.v1 artifact, verified against the published JWKS. Use it BEFORE a material first payment to an unfamiliar resource, or after cached evidence expires. The decision denominator is CUMULATIVE exposure before the artifact expires — planned spend across all intended calls, or the expected cost of one failure, whichever is larger — not the price of the next call: an agent planning 100 calls to a 1¢ endpoint should check; an agent making a single 1¢ call should not. Skip it when cumulative exposure is at or below the 1¢ check price. Returns signed observational evidence with explicit freshness — NOT a guarantee, insurance, or endorsement. Network side effect: one HTTPS request to the Signal endpoint; payment side effect: the 1¢ x402 purchase on uncached calls.

Input parameters:

- `agent` (string): Optional name of a stored x402 payer agent (delegated mode).
- `resource` (string, required): The exact absolute HTTPS URL of the x402 resource you are about to pay. Signal evidence is keyed by this exact URL.

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp#diagnostics

## Score history

- 2026-09-25: 83
- 2026-09-24: 83
- 2026-09-23: 83
- 2026-09-22: 82
- 2026-09-21: 82
- 2026-09-20: 81
- 2026-09-19: 81
- 2026-09-18: 80
- 2026-09-17: 80
- 2026-09-16: 79
- 2026-09-15: 79
- 2026-09-14: 79
- 2026-09-13: 78
- 2026-09-12: 78
- 2026-09-11: 77
- 2026-09-10: 77
- 2026-09-09: 76
- 2026-09-08: 76
- 2026-09-07: 75
- 2026-09-06: 75
- 2026-09-05: 74
- 2026-09-04: 74
- 2026-09-03: 73
- 2026-09-02: 68
- 2026-09-01: 72
- 2026-08-31: 72
- 2026-08-30: 72
- 2026-08-29: 71
- 2026-08-28: 71
- 2026-08-27: 55

## Common questions

### What is the io.github.stevemilton/x402-payagent-mcp server?

io.github.stevemilton/x402-payagent-mcp is listed in the public MCP registry as io.github.stevemilton/x402-payagent-mcp. Pay x402 APIs in USDC on Base, Solana, and BNB Chain with spend mandates, receipts, idempotency. This page covers its npm package (@arispay/payagent-mcp).

### Is the io.github.stevemilton/x402-payagent-mcp server safe to use?

io.github.stevemilton/x402-payagent-mcp scores 83 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 25 September 2026. It declares no install or post-install scripts. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the io.github.stevemilton/x402-payagent-mcp server expose?

io.github.stevemilton/x402-payagent-mcp exposes 7 tools: setup, discover, inspect, pay, balance, and 2 more. Their descriptions and schemas cost roughly 1,209 tokens of context every time the server is loaded.

### Is the io.github.stevemilton/x402-payagent-mcp server still maintained?

io.github.stevemilton/x402-payagent-mcp is still listed as active in the MCP registry. We last reached this channel on 25 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What licence is the io.github.stevemilton/x402-payagent-mcp server under?

io.github.stevemilton/x402-payagent-mcp declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- npm package: https://www.npmjs.com/package/@arispay/payagent-mcp
- Socket report: https://socket.dev/npm/package/@arispay/payagent-mcp
- Repository: https://github.com/arispay-inc/payagent-mcp
- Website: https://arispay.app/
- Changelog RSS feed: https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp.json
- HTML version of this page: https://verifymcp.io/servers/stevemilton-x402-payagent-mcp/arispay-payagent-mcp