How do I connect an AI agent to blackwall-x402-guardrail?

Use the MCP streamable HTTP endpoint https://mcp.blackwalltier.com.

Faceabot

Catalog › com.blackwalltier/blackwall-x402-guardrail

Is blackwall-x402-guardrail reliable?

Being measured Measurement in progress: 1 check(s) so far. A verdict needs at least 3 checks.

En français : Mesure en cours. Faceabot teste cet outil lui-même, en continu, sans dépendre de ce que son auteur affirme.

What it does

Keyless hosted MCP: pre-signature x402 payment verdict (GO/HOLD/STOP) with a signed receipt.

Source: official MCP registry (registry.modelcontextprotocol.io) · version 0.1.2 · publisher website

Connect your agent

{
  "mcpServers": {
    "blackwall-x402-guardrail": {
      "url": "https://mcp.blackwalltier.com"
    }
  }
}

Or ask Faceabot first: MCP tool check_reliability {"id":"com.blackwalltier/blackwall-x402-guardrail"} on https://faceabot.com/api/mcp.

Does it actually do the job?

Not tested with a real task yet. Faceabot only runs real tasks on tools that declare themselves read-only (readOnlyHint), with a neutral sample input.

Faceabot measurements

When	Answers	Real task	Latency
2026-10-06 12:05 UTC	✅ ok	—	4077 ms

Method: MCP initialize then tools/list from Faceabot (FaceabotProbe/1.0), plus one read-only tool call with a neutral input when the server declares one, repeated over time. This checks that the server is up and speaks MCP correctly; it does not certify the quality or safety of each tool. How measurement works.

More from the same publisher

blackwall Not measured yet

API-key pre-action risk gate: any irreversible agent action (money, SQL, delete, email).

Package npm : blackwall-mcp · website · measurements and details

Publisher of blackwall-x402-guardrail?

Show your measured reliability on your README or website:

[![Measured by Faceabot](https://faceabot.com/badge/com.blackwalltier/blackwall-x402-guardrail.svg)](https://faceabot.com/tools/com.blackwalltier/blackwall-x402-guardrail)

Data in JSON: /api/catalog?id=com.blackwalltier/blackwall-x402-guardrail · Stop probes: POST /api/reliability/opt-out

AI agents: all of this is available without keys over MCP https://faceabot.com/api/mcp · HTTP https://faceabot.com/api/catalog?q=… · Guide : llms.txt

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