About NullClear Arbiter
NullClear Arbiter is an MCP server for agents making HTTP 402 transactions through NullClear. It provides reputation checks, deferred schema escrow, and mandate verification to inform transaction decisions.
Key features
- 01On-chain reputation checks
- 02Deferred schema escrow for HTTP 402 calls
- 03Zero-spend handling for failures or malformed data
- 04KYA mandate and transaction-limit verification
Use cases
- 01Check an agent's clearing reliability before a transaction
- 02Make an HTTP 402 call with deferred escrow
- 03Verify liability backing and transaction limits
MCP support
The server exposes tools to MCP clients for reputation queries, escrow-backed HTTP 402 calls, and KYA mandate verification.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://api.nullclear.dev/mcpclaude mcp add --transport http mithgalalfayez-nullclear https://api.nullclear.dev/mcp{"mcpServers":{"mithgalalfayez-nullclear":{"type":"http","url":"https://api.nullclear.dev/mcp"}}}Open in Cursor{"servers":{"mithgalalfayez-nullclear":{"type":"http","url":"https://api.nullclear.dev/mcp"}}}Open in VS Code{"mcpServers":{"mithgalalfayez-nullclear":{"type":"http","url":"https://api.nullclear.dev/mcp"}}}{"mcpServers":{"mithgalalfayez-nullclear":{"serverUrl":"https://api.nullclear.dev/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
3| Parameter | Type | Required | Description |
|---|---|---|---|
| agentId | string | Yes | The ERC-8004 agent token ID or registered identifier (e.g. '124595') |
| chainId | number | No | Base chain ID (8453 for Mainnet, 84532 for Sepolia) |
Details
From the project README@nullclear/mcp
Model Context Protocol (MCP) server enabling autonomous AI agents (Claude Desktop, Cursor, Gemini, OpenAI Agents) to safely transact over HTTP 402 with NullClear deferred escrow and reputation scoring.
Exposed Tools
nullclear_check_reputation: Query an agent's on-chain trust score, clearing reliability, and Sybil wash-trade penalty flags.nullclear_escrow_x402_call: Perform an HTTP 402 call with deferred non-custodial schema escrow, guaranteeing $0 spent if the counterparty agent fails or returns malformed data.nullclear_verify_kya_mandate: Verify an agent's legal corporate liability backing and per-transaction limits.
Configuration
Add to your MCP client config (e.g., claude_desktop_config.json):
{
"mcpServers": {
"nullclear": {
"command": "node",
"args": ["/path/to/nullclear/packages/mcp-server/dist/index.js"],
"env": {
"ARBITER_URL": "https://arbiter.nullclear.dev",
"BUYER_PRIVATE_KEY": "0x..."
}
}
}
}
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.