# dev.x402check/mcp

> Preflight before paying any x402 tool (ok|caution|avoid + history). 1 free/wallet; then $0.01 Base.

- name: dev.x402check/mcp
- version: 0.1.6
- connection class: R0 (autonomous)
- trust: 82/100 flags: no-repository
- quality: 89/100 (new)
- owner: not claimed
- descriptor: https://api.protogrid.dev/v1/servers/dev.x402check%2Fmcp
- tools: https://api.protogrid.dev/v1/servers/dev.x402check%2Fmcp/tools

**An agent can connect right now, no human step.** Remote endpoint, no authentication, reachable on the last probe.

## Connection (mcpServers)

```json
{
  "mcpServers": {
    "x402check": {
      "type": "http",
      "url": "https://x402check.dev/mcp"
    }
  }
}
```


## Trust

- hygiene: 80
- liveness: 99
- freshness: 100
- provenance: 55
- drivers: +dns-namespace +website +reachable +uptime-96% +updated-5d-ago -no-repository
- Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed.

## Quality 89/100 (new)

### protocol: 75 (weight 25)

- warn `protocol.modern`: newest supported version is 2024-11-05; 2026-07-28 not supported, older versions are deprecated until 2027-07-28
- n/a `protocol.stateless`: only applies to 2026-07-28 servers
- pass `protocol.transport`: streamable HTTP
- n/a `protocol.list_ttl`: only applies to 2026-07-28 servers

### authorization: n/a (weight 15)

- n/a `auth.prm`, `auth.as_metadata`, `auth.cimd`: no remote uses OAuth
- n/a `auth.secret_in_url`: no templated URL

### tool hygiene: 100 (weight 30)

- pass `tools.descriptions`: every tool has a description
- pass `tools.description_length`: descriptions are concise
- pass `tools.schemas`: every tool has an object input schema
- pass `tools.annotations`: 6 of 6 tools declare readOnlyHint or destructiveHint
- pass `tools.directory_hints`: every tool declares readOnlyHint, destructiveHint, idempotentHint and openWorldHint
- pass `tools.token_cost`: about 1,095 tokens to load every tool
- pass `tools.api_dump`: tools are not a one-to-one API dump

### stability: n/a (weight 15)

- n/a `stability.changes`, `stability.rug_pull`: tool history recorded for 6 of the 7 days needed

### dependencies: n/a (weight 15)

- n/a `deps.known_vulns`, `deps.mcp_sdk_version`, `deps.resolvable`: deps.dev does not know x402check-mcp@0.1.6

- tools: 6, about 1,095 tokens to load them all
- tool set hash: 294fdac8c14a55d5ea8e5dfba23e3007
- tools last changed: 2026-11-04T03:03:34.032Z
- badge: [![protogrid quality](https://protogrid.dev/badge/dev.x402check/mcp.svg)](https://protogrid.dev/servers/dev.x402check/mcp)
- Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed.

### Tool changes

- 2026-11-04 `watch_tool` changed (annotations)
- 2026-11-04 `deep_check` changed (annotations)
- 2026-11-04 `compare_tools` changed (annotations)
- 2026-11-04 `preflight_batch` changed (annotations)
- 2026-11-04 `verify_payto` changed (annotations)
- 2026-11-04 `preflight_check` changed (description, annotations)
  - before: Preflight before paying any x402 tool. Mandatory check before settle / PAYMENT-SIGNATURE. Pass the absolute https seller URL. Returns verdict ok|caution|avoid plus that tool's history only (uptime, payToChanges, priceChanges). Use when: about to pay any x402 endpoint; asking is this API a scam; is this endpoint safe or legit; debugging a failing 402; checking uptime; validating payment requirements before signing USDC on Base. Do not pay if verdict=avoid. Charged $0.01 per URL via x402 Exact on this MCP tools/call (params._meta['x402/payment']).
  - after: Preflight an x402 seller URL before settle / PAYMENT-SIGNATURE. Pass the absolute https seller URL. Returns verdict ok|caution|avoid plus that tool's history only (uptime, payToChanges, priceChanges). Use when: about to pay any x402 endpoint; asking is this API a scam; is this endpoint safe or legit; debugging a failing 402; checking uptime; validating payment requirements before signing USDC on Base. Do not pay if verdict=avoid. Charged $0.01 per URL via x402 Exact on this MCP tools/call (params._meta['x402/payment']).
- 2026-11-02 `preflight_check` changed (description)
  - before: Mandatory check before paying any x402 endpoint. Pass the absolute https seller URL. Returns verdict ok|caution|avoid plus that tool's history only (uptime, payToChanges, priceChanges). Use when: about to settle / PAYMENT-SIGNATURE; asking is this API a scam; is this endpoint safe or legit; debugging a failing 402; checking uptime; validating payment requirements before signing USDC on Base. Do not pay if verdict=avoid. Charged $0.01 per URL via x402 Exact on this MCP tools/call (params._meta['x402/payment']).
  - after: Preflight before paying any x402 tool. Mandatory check before settle / PAYMENT-SIGNATURE. Pass the absolute https seller URL. Returns verdict ok|caution|avoid plus that tool's history only (uptime, payToChanges, priceChanges). Use when: about to pay any x402 endpoint; asking is this API a scam; is this endpoint safe or legit; debugging a failing 402; checking uptime; validating payment requirements before signing USDC on Base. Do not pay if verdict=avoid. Charged $0.01 per URL via x402 Exact on this MCP tools/call (params._meta['x402/payment']).
- 2026-11-02 `watch_tool` added
  - Subscribe to daily re-checks of one x402 seller URL for 30 days. Alerts your webhook and/or email when payTo, price, network, or availability changes. Fixed $5 USDC Exact (not per-check). Optional after a one-shot preflight when you will revisit the same seller.
- 2026-11-02 `deep_check` added
  - Deeper trust check before paying an x402 endpoint ($0.05 Exact USDC). Runs the same live 402 + history as preflight_check, then repeated probes for payTo/price consistency, a recent public Base USDC-to-payTo transfer sample, Bazaar + 402 Index listing checks, and drift vs last KV history. Does not claim OFAC or wallet simulation. Optional when the base check is not enough signal.
- 2026-11-02 `compare_tools` changed (description)
  - before: Compare several x402 tools before choosing which to pay. Alias of preflight_batch: returns each URL's verdict, priceUsd, payTo, uptimePct, and drift history so you can pick reliable/cheap candidates and skip avoid. Charged per URL.
  - after: Compare several x402 tools before choosing which to pay. Alias of preflight_batch: returns each URL's verdict, priceUsd, payTo, uptimePct, and drift history so you can pick reliable/cheap candidates and skip avoid. Charged per URL via MCP x402 payment.

Full history: https://api.protogrid.dev/v1/servers/dev.x402check%2Fmcp/changes

## Dependencies

- npm x402check-mcp@0.1.6: unknown

Dependency graphs from deps.dev; advisories from OSV.dev, including the GitHub Advisory Database and the PyPI Advisory Database; all CC BY 4.0.

## Remotes

- https://x402check.dev/mcp (streamable-http, auth none, reachable true, uptime30d 0.962963)

## Packages

- npm x402check-mcp@0.1.6

## Tools (6)

- `compare_tools`: Compare several x402 tools before choosing which to pay. Alias of preflight_batch: returns each URL's verdict, priceUsd, payTo, uptimePct, and drift history so you can pick reliable/cheap candidates and skip avoid. Charged per URL via MCP x402 payment.
- `deep_check`: Deeper trust check before paying an x402 endpoint ($0.05 Exact USDC). Runs the same live 402 + history as preflight_check, then repeated probes for payTo/price consistency, a recent public Base USDC-to-payTo transfer sample, Bazaar + 402 Index listing checks, and drift vs last KV history. Does not claim OFAC or wallet simulation. Optional when the base check is not enough signal.
- `preflight_batch`: Trust-check up to 25 x402 seller URLs in one request. Charged per URL (N × unit) in a single Exact settlement via MCP _meta payment. Prefer when comparing candidates, picking the cheapest/most reliable, or screening Bazaar search hits before paying any of them.
- `preflight_check`: Preflight an x402 seller URL before settle / PAYMENT-SIGNATURE. Pass the absolute https seller URL. Returns verdict ok|caution|avoid plus that tool's history only (uptime, payToChanges, priceChanges). Use when: about to pay any x402 endpoint; asking is this API a scam; is this endpoint safe or legit; debugging a failing 402; checking uptime; validating payment requirements before signing USDC on Base. Do not pay if verdict=avoid. Charged $0.01 per URL via x402 Exact on this MCP tools/call (params._meta['x402/payment']).
- `verify_payto`: Verify the payTo / receiving wallet an x402 seller demands before you sign. Same check as preflight_check: live 402 probe + history.payToChanges (wallet rotations) and priceChanges. Use when confirming which Base USDC address you will pay, comparing payTo to an allowlist, or detecting a rug-style wallet swap. Charged per URL via MCP x402 payment.
- `watch_tool`: Subscribe to daily re-checks of one x402 seller URL for 30 days. Alerts your webhook and/or email when payTo, price, network, or availability changes. Fixed $5 USDC Exact (not per-check). Optional after a one-shot preflight when you will revisit the same seller.