Otr Protocol

Merchant trust verification for AI agents. One call = trust score, badge, and purchase safety.

Quick Install

Automated & IDE Setup

Copy the AI prompt to install this server into Claude Code, Cursor, or another agent — or use 1-click editor setup below.

Add to Cursor Add to VS Code

Manual Client & Custom JSON ConfigExpand JSON ▾

Client Config & Setup

Choose your client or environment

Target File:~/Library/Application Support/Claude/claude_desktop_config.json

claude_desktop_config.json

{
  "mcpServers": {
    "otr-protocol": {
      "command": "npx",
      "args": [
        "-y",
        "otr-protocol"
      ]
    }
  }
}

💡 Paste the JSON block into your client's configuration file under mcpServers, then restart the application.

Documentation Overview

OTR Protocol

The merchant trust layer for AI agent commerce
Deterministic, verifiable, open-source merchant trust scoring for the agentic economy
Protocol v4.1

Specification • Scoring Algorithm • Quick Start • Packages • Contributing

The Problem

AI agents are increasingly making purchase decisions on behalf of consumers. The agentic commerce stack is taking shape -- but there is a critical missing layer:

Code

┌──────────────────────────────────────────────────────────────────┐
│                  AI Agent Commerce Protocol Stack                 │
├──────────────────────────────────────────────────────────────────┤
│                                                                   │
│   Visa TAP ·············· Agent Identity Verification             │
│   Google UCP ············ Structured Data Exchange                 │
│   Stripe ACP ············ Payment Processing                      │
│                                                                   │
│   ┌───────────────────────────────────────────────────────────┐   │
│   │  OTR Protocol ·····  MERCHANT TRUST VERIFICATION  ◀━━━━━ │   │
│   │                      "Is this merchant safe to buy from?" │   │
│   └───────────────────────────────────────────────────────────┘   │
│                                                                   │
│   Visa TAP answers "Who is the AI agent?"                         │
│   Google UCP answers "What products are available?"               │
│   Stripe ACP answers "How do I pay?"                              │
│   OTR answers "Should I trust this merchant?"  ◀━━ ONLY OTR      │
│                                                                   │
└──────────────────────────────────────────────────────────────────┘

Without OTR, AI agents operate blind -- unable to distinguish a legitimate retailer from a sophisticated scam site. This exposes consumers to fraud and erodes trust in the entire agentic commerce ecosystem.

The Solution

OTR (Open Trust Registry) provides deterministic, verifiable merchant trust scores using 6 verification dimensions, a 10-layer anti-fraud pipeline (Layer 0: Google Web Risk one-vote veto + Layers 1-9: core detection engine), and three-layer immutable audit trail. It is fully open-source (MIT), machine-readable, and designed from the ground up for AI agent consumption.

Key Properties

Deterministic -- Same inputs always produce identical outputs. Any validator can reproduce any score.
Verifiable -- All data sources are publicly accessible. No hidden factors or proprietary signals.
Unforgeable -- Verification dimension weighted at 40% in public assessment. SEC filings, Wikidata entries, and 10-year domain age cannot be faked.
Tamper-proof -- SHA-256 hash chain + Base L2 blockchain anchoring + IPFS monthly snapshots.
Fair -- No pay-for-trust. Scores reflect behavior, not subscription level.
Category-aware -- Three site categories (ecommerce / saas / non_commerce) with tailored scoring weights.
Safety-first -- Google Web Risk Layer 0 one-vote veto: flagged domains get score=0, status SUSPENDED.

Quick Start

bash

# Verify any merchant instantly
npx @otr-protocol/validator verify nike.com

# Output:
# ┌──────────────────────────────────────────────┐
# │  nike.com                             GOLD   │
# │  Trust Score: 88/100   Category: ecommerce   │
# │  OTR-ID: OTR-1C-7F3A2B9E4D1C-K4             │
# │                                              │
# │  Verification:   85  ██████████████░░        │
# │  Security:       80  █████████████░░░        │
# │  Governance:     72  ████████████░░░░        │
# │  Transparency:   75  ████████████░░░░        │
# │  Data Quality:   65  ██████████░░░░░░        │
# │  Fulfillment:    --  (COLD mode)             │
# └──────────────────────────────────────────────┘

For AI Agents (MCP Server)

The OTR MCP Server uses the standard Model Context Protocol and works with all MCP-compatible clients.

Claude Desktop / Claude Code -- add to claude_desktop_config.json:

config.json

{
  "mcpServers": {
    "otr": {
      "command": "npx",
      "args": ["@otr-protocol/mcp-server"]
    }
  }
}

Cursor / Windsurf / Cline -- same configuration in .cursor/mcp.json or equivalent. Any client implementing the MCP specification works out of the box.

Now any AI agent can verify merchants in natural language:

"Is nike.com trustworthy?" --> OTR returns trust score 88/100, badge GOLD, and a 6-dimension breakdown (Verification, Security, Governance, Transparency, DataQuality, Fulfillment) with evidence sources.

Two MCP Tools — One Call = Complete Answer

Tool	Description	Returns
`verify_merchant`	Complete merchant profile in one call	Trust score (0-100), badge, 6-dimension breakdown, safety status (Google Web Risk), site classification (ecommerce/saas/non_commerce), entity data, policy URLs, data sources
`search_registry`	Search the OTR merchant registry	Paginated merchant list with scores, badges, and recommendations

Design philosophy: AI agents should get everything they need in a single tool call. verify_merchant returns trust assessment + purchase capabilities + links + policy URLs + data freshness — no need to chain multiple calls.

TypeScript SDK

server.ts

import { OtrClient } from "@otr-protocol/sdk";

const otr = new OtrClient();
const result = await otr.verify("nike.com");

console.log(result.trustScore);   // 88
console.log(result.badge);        // "GOLD"
console.log(result.dimensions);   // { verification: 85, security: 80, ... }

// Search the registry
const results = await otr.search("electronics", { minScore: 70 });

Core Scoring Engine

server.ts

import { calculateTrustScore } from "@otr-protocol/core";

// Deterministic: same inputs always produce identical outputs
const result = calculateTrustScore({
  hasSecFiling: true,
  hasStockSymbol: true,
  stockExchange: "NYSE",
  hasWikidataId: true,
  trancoRank: 500,
  domainAgeYears: 15,
  // ... 40+ evidence fields
});

console.log(result.trustScore);  // 88
console.log(result.badge);       // "GOLD"
console.log(result.tier);        // "TIER_4"

Architecture

Read the full README →View source on GitHub →

Related MCP Servers

View all in Developer Tools View all alternatives

Reviews

No reviews yet — be the first to share how this listing worked for you.

Frequently Asked Questions about Otr Protocol

Add the following block to your claude_desktop_config.json under mcpServers: "mcpServers": { "otr-protocol": { "command": "npx", "args": ["-y", "otr-protocol"] } }

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Technical Specs & Signals

CategoryDeveloper Tools

27Quality signal: Emerging · 27/100How this signal is calculated ▾

Server availabilityNot measured

Not scored for repo-hosted servers — we can't reach the running server, only its GitHub page. Hosted MCP endpoints are health-checked live.

Verified ownership8/20

Documentation & tools11/30

Adoption & activity1/15

Community engagement0/10

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More in 💻 Developer Tools →Best MCP servers for Developers →Alternatives to Otr Protocol →Install in Claude Desktop Install in Cursor Install in VS Code

Otr Protocol

Merchant trust verification for AI agents. One call = trust score, badge, and purchase safety.

Quick Install

Automated & IDE Setup

Copy the AI prompt to install this server into Claude Code, Cursor, or another agent — or use 1-click editor setup below.

Add to Cursor Add to VS Code

Manual Client & Custom JSON ConfigExpand JSON ▾

Client Config & Setup

Choose your client or environment

Target File:~/Library/Application Support/Claude/claude_desktop_config.json

claude_desktop_config.json

{
  "mcpServers": {
    "otr-protocol": {
      "command": "npx",
      "args": [
        "-y",
        "otr-protocol"
      ]
    }
  }
}

💡 Paste the JSON block into your client's configuration file under mcpServers, then restart the application.

Documentation Overview

OTR Protocol

The merchant trust layer for AI agent commerce
Deterministic, verifiable, open-source merchant trust scoring for the agentic economy
Protocol v4.1

Specification • Scoring Algorithm • Quick Start • Packages • Contributing

The Problem

AI agents are increasingly making purchase decisions on behalf of consumers. The agentic commerce stack is taking shape -- but there is a critical missing layer:

Code

┌──────────────────────────────────────────────────────────────────┐
│                  AI Agent Commerce Protocol Stack                 │
├──────────────────────────────────────────────────────────────────┤
│                                                                   │
│   Visa TAP ·············· Agent Identity Verification             │
│   Google UCP ············ Structured Data Exchange                 │
│   Stripe ACP ············ Payment Processing                      │
│                                                                   │
│   ┌───────────────────────────────────────────────────────────┐   │
│   │  OTR Protocol ·····  MERCHANT TRUST VERIFICATION  ◀━━━━━ │   │
│   │                      "Is this merchant safe to buy from?" │   │
│   └───────────────────────────────────────────────────────────┘   │
│                                                                   │
│   Visa TAP answers "Who is the AI agent?"                         │
│   Google UCP answers "What products are available?"               │
│   Stripe ACP answers "How do I pay?"                              │
│   OTR answers "Should I trust this merchant?"  ◀━━ ONLY OTR      │
│                                                                   │
└──────────────────────────────────────────────────────────────────┘

The Solution

Key Properties

Deterministic -- Same inputs always produce identical outputs. Any validator can reproduce any score.
Verifiable -- All data sources are publicly accessible. No hidden factors or proprietary signals.
Unforgeable -- Verification dimension weighted at 40% in public assessment. SEC filings, Wikidata entries, and 10-year domain age cannot be faked.
Tamper-proof -- SHA-256 hash chain + Base L2 blockchain anchoring + IPFS monthly snapshots.
Fair -- No pay-for-trust. Scores reflect behavior, not subscription level.
Category-aware -- Three site categories (ecommerce / saas / non_commerce) with tailored scoring weights.
Safety-first -- Google Web Risk Layer 0 one-vote veto: flagged domains get score=0, status SUSPENDED.

Quick Start

bash

# Verify any merchant instantly
npx @otr-protocol/validator verify nike.com

# Output:
# ┌──────────────────────────────────────────────┐
# │  nike.com                             GOLD   │
# │  Trust Score: 88/100   Category: ecommerce   │
# │  OTR-ID: OTR-1C-7F3A2B9E4D1C-K4             │
# │                                              │
# │  Verification:   85  ██████████████░░        │
# │  Security:       80  █████████████░░░        │
# │  Governance:     72  ████████████░░░░        │
# │  Transparency:   75  ████████████░░░░        │
# │  Data Quality:   65  ██████████░░░░░░        │
# │  Fulfillment:    --  (COLD mode)             │
# └──────────────────────────────────────────────┘

For AI Agents (MCP Server)

The OTR MCP Server uses the standard Model Context Protocol and works with all MCP-compatible clients.

Claude Desktop / Claude Code -- add to claude_desktop_config.json:

config.json

{
  "mcpServers": {
    "otr": {
      "command": "npx",
      "args": ["@otr-protocol/mcp-server"]
    }
  }
}

Cursor / Windsurf / Cline -- same configuration in .cursor/mcp.json or equivalent. Any client implementing the MCP specification works out of the box.

Now any AI agent can verify merchants in natural language:

"Is nike.com trustworthy?" --> OTR returns trust score 88/100, badge GOLD, and a 6-dimension breakdown (Verification, Security, Governance, Transparency, DataQuality, Fulfillment) with evidence sources.

Two MCP Tools — One Call = Complete Answer

Tool	Description	Returns
`verify_merchant`	Complete merchant profile in one call	Trust score (0-100), badge, 6-dimension breakdown, safety status (Google Web Risk), site classification (ecommerce/saas/non_commerce), entity data, policy URLs, data sources
`search_registry`	Search the OTR merchant registry	Paginated merchant list with scores, badges, and recommendations

TypeScript SDK

server.ts

import { OtrClient } from "@otr-protocol/sdk";

const otr = new OtrClient();
const result = await otr.verify("nike.com");

console.log(result.trustScore);   // 88
console.log(result.badge);        // "GOLD"
console.log(result.dimensions);   // { verification: 85, security: 80, ... }

// Search the registry
const results = await otr.search("electronics", { minScore: 70 });

Core Scoring Engine

server.ts

import { calculateTrustScore } from "@otr-protocol/core";

// Deterministic: same inputs always produce identical outputs
const result = calculateTrustScore({
  hasSecFiling: true,
  hasStockSymbol: true,
  stockExchange: "NYSE",
  hasWikidataId: true,
  trancoRank: 500,
  domainAgeYears: 15,
  // ... 40+ evidence fields
});

console.log(result.trustScore);  // 88
console.log(result.badge);       // "GOLD"
console.log(result.tier);        // "TIER_4"

Architecture

Read the full README →View source on GitHub →

Related MCP Servers

View all in Developer Tools View all alternatives

Reviews

No reviews yet — be the first to share how this listing worked for you.

Frequently Asked Questions about Otr Protocol

Add the following block to your claude_desktop_config.json under mcpServers: "mcpServers": { "otr-protocol": { "command": "npx", "args": ["-y", "otr-protocol"] } }

AllMCPs Directory Badge

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Showcase your server listing on GitHub or your project documentation. Embed this dynamic SVG badge to highlight official listing status and live engagement.

Badge Style:

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[![AllMCPs](https://allmcps.com/api/badge/otr-protocol?style=directory)](https://allmcps.com/mcp/otr-protocol)

HTML Embed

<a href="https://allmcps.com/mcp/otr-protocol"><img src="https://allmcps.com/api/badge/otr-protocol?style=directory" alt="Otr Protocol on AllMCPs" /></a>

Technical Specs & Signals

CategoryDeveloper Tools

27Quality signal: Emerging · 27/100How this signal is calculated ▾

Server availabilityNot measured

Not scored for repo-hosted servers — we can't reach the running server, only its GitHub page. Hosted MCP endpoints are health-checked live.

Verified ownership8/20

Documentation & tools11/30

Adoption & activity1/15

Community engagement0/10

★ Spotlight Slot

Feature Your MCP Server

Get maximum visibility for your server across our directory, search results, and detail pages.

Spotlight Your Server

Own this project?

Free dofollow backlink: add your website and place the AllMCPs badge on it — no claim needed. We detect it automatically and keep it verified as long as the badge stays live.

Claim & get free dofollow

Share & Embed

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More in 💻 Developer Tools →Best MCP servers for Developers →Alternatives to Otr Protocol →Install in Claude Desktop Install in Cursor Install in VS Code