# NullClear Arbiter (npm · @nullclear/mcp)

Autonomous x402 payment schema-escrow arbiter, spend firewall, failover & ERC-8004 Sybil oracle

- Trust score: 67/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-17

## Components

- remote · `api.nullclear.dev`: 64/100, [markdown](https://verifymcp.io/servers/mithgalalfayez-nullclear/api.md), [page](https://verifymcp.io/servers/mithgalalfayez-nullclear/api)
- npm · `@nullclear/mcp`: 67/100 (this document), [markdown](https://verifymcp.io/servers/mithgalalfayez-nullclear/nullclear-mcp.md), [page](https://verifymcp.io/servers/mithgalalfayez-nullclear/nullclear-mcp)

## Channel facts

- Registry: `npm`
- Package: `@nullclear/mcp`
- Version: `1.1.1`
- 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 2026-10-17.

- **Supply Chain Security**: 99/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - 31 of 111 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 0 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 64/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 524 tokens (~174/item across 3 items; 3 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 0/100
  - Stability observed for 0 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 98/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 94% of tool parameters carry a description.
- **Tool Safety**: 75/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - 0 of 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "nullclear_escrow_x402_call" implies "execute" and declares no destructiveHint at all, which the MCP spec reads as destructive by default.
  - An AI judge read all 3 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.

**Unverified: 1 category.** A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

## Install

### How do I install the NullClear Arbiter MCP server?

NullClear Arbiter runs locally as an npm package, launched with npx -y @nullclear/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 mithgalalfayez-nullclear -- npx -y @nullclear/mcp
```

### Cursor

```json
{
  "mcpServers": {
    "mithgalalfayez-nullclear": {
      "command": "npx",
      "args": [
        "-y",
        "@nullclear/mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "mithgalalfayez-nullclear": {
      "command": "npx",
      "args": [
        "-y",
        "@nullclear/mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add mithgalalfayez-nullclear -- npx -y @nullclear/mcp
```

### opencode

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

### OpenClaw

```bash
openclaw mcp add mithgalalfayez-nullclear --command npx --arg -y --arg @nullclear/mcp
```

### Hermes

```yaml
mcp_servers:
  mithgalalfayez-nullclear:
    command: "npx"
    args: ["-y", "@nullclear/mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "mithgalalfayez-nullclear": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "@nullclear/mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add mithgalalfayez-nullclear -t stdio -c npx -a -y @nullclear/mcp
```

### Other

```json
{
  "mcpServers": {
    "mithgalalfayez-nullclear": {
      "command": "npx",
      "args": [
        "-y",
        "@nullclear/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.

### 2026-10-17 (score 67, +28)

- [security improvement] Injection markers: unverified → pass
- [security] First check of Judged manipulation: pass
- [functional improvement] Tool coverage: unverified → 100
- [functional improvement] Stability: unverified → 0.00
- [functional improvement] MCP protocol: unverified → pass
- [functional] First check of Schema quality: fail
- [functional] First check of Schema quality: fail
- [functional] First check of Tool coverage: 94
- [functional] First check of Destructive annotations: 0
- [functional] First check of Schema quality: good

### 2026-10-16 (score 39)

First indexed and scored.

## MCP tools (3)

### `nullclear_check_reputation` (~85 tokens)

Inspect an AI agent's trust score (0-100), clearing reliability, Sybil wash-trade penalty flags, and corporate KYA backing on Base

Input parameters:

- `agentId` (string, required): The ERC-8004 agent token ID or registered identifier
- `chainId` (number): Base chain ID (8453 for Mainnet, 84532 for Sepolia)

### `nullclear_escrow_x402_call` (~346 tokens)

Execute an x402-gated HTTP API call through NullClear deferred schema escrow. The arbiter guarantees payment is only settled if upstream returns valid data matching your schema contract. If the seller hallucinates or crashes, $0 is spent. Users can test immediately against https://api.nullclear.dev/v1/sandbox/market-feed (or fail over from https://api.nullclear.dev/v1/sandbox/hallucinating-seller to https://api.nullclear.dev/v1/sandbox/market-feed) with zero wallet setup.

Input parameters:

- `buyerPrivateKey` (string): Optional buyer private key (defaults to BUYER_PRIVATE_KEY environment variable)
- `fallbacks` (array): Ordered fallback candidates for autonomous multi-seller failover routing (max 3)
- `invariants` (array): Deep value invariants (numeric bounds, regex, forbidden substrings, timestamp freshness)
- `jsonSchema` (object): JSON Schema draft-07 contract that response must strictly satisfy
- `method` (string)
- `minTrustScore` (number): Minimum acceptable trust score for seller (0-100, default 50)
- `rejectRefusals` (boolean): Reject canonical LLM refusal strings (default: true)
- `requiredFields` (array): Dot-notation field paths that must exist in response (e.g. ['data.price'])
- `sellerAgentId` (string): Seller's agent ID for reputation check and Sybil wash-trade gating
- `spendPolicy` (object): Outbound spend firewall limits (maxPerCallAtomic, maxDailyWalletAtomic)
- `targetUrl` (string, required): Upstream API endpoint demanding x402 payment

### `nullclear_verify_kya_mandate` (~93 tokens)

Verify an agent's Know Your Agent (KYA) corporate liability mandate, active validity, and whether a proposed transaction amount is within corporate limits

Input parameters:

- `agentId` (string, required): The ERC-8004 agent token ID
- `chainId` (number): Base chain ID (default 8453)
- `transactionAmountUsd` (number, required): Amount in USD intended to spend in the transaction

## Diagnostics

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

## Score history

- 2026-10-17: 67
- 2026-10-16: 39

## Common questions

### What is the NullClear Arbiter MCP server?

NullClear Arbiter is an MCP server listed in the public MCP registry as io.github.mithgalalfayez/nullclear. Autonomous x402 payment schema-escrow arbiter, spend firewall, failover & ERC-8004 Sybil oracle. This page covers its npm package (@nullclear/mcp).

### Is the NullClear Arbiter MCP server safe to use?

NullClear Arbiter scores 67 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 17 October 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 NullClear Arbiter MCP server expose?

NullClear Arbiter exposes 3 tools: nullclear_check_reputation, nullclear_escrow_x402_call, nullclear_verify_kya_mandate. Their descriptions and schemas cost roughly 524 tokens of context every time the server is loaded.

### Is the NullClear Arbiter MCP server still maintained?

NullClear Arbiter is still listed as active in the MCP registry. We last reached this channel on 17 October 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 NullClear Arbiter MCP server under?

NullClear Arbiter 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/@nullclear/mcp
- Socket report: https://socket.dev/npm/package/@nullclear/mcp
- Repository: https://github.com/Nullclear-Protocol/nullclear
- Website: https://nullclear.dev/
- Changelog RSS feed: https://verifymcp.io/servers/mithgalalfayez-nullclear/nullclear-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/mithgalalfayez-nullclear/nullclear-mcp.json
- HTML version of this page: https://verifymcp.io/servers/mithgalalfayez-nullclear/nullclear-mcp