@juny-klave/mcp

MCP server that gives Claude the ability to negotiate prices on your behalf — autonomously, privately, and with cryptographic proof of the outcome.

What it does

KLAVE connects Claude to a bilateral negotiation engine. You describe what you want in plain English; Claude calls KLAVE, runs the negotiation through multiple rounds, and reports back with the settled price and a ZK proof reference. Your ceiling is cryptographically bound to the authorization token and never appears in any response — the seller never sees your budget.

What You Can Negotiate

Anything with a price. KLAVE does not require pre-existing listings, platform partnerships, or pre-seeded scenarios. If it has an asking price and you have a ceiling, KLAVE can negotiate it.

Freight and logistics

"Negotiate 200 FEU containers Shanghai to Rotterdam. They're asking $2,806. My ceiling is $2,700."

Software and SaaS

"Get me a better price on this CRM license. 500 seats, they want $75,000 annually. I won't go above $58,000."

Employment and contracts

"A contractor is asking $185/hour for a 6-month engagement. My budget is $150/hour. Negotiate it."

Real estate

"Negotiate our office lease renewal. Landlord wants $42/sqft. We need to be at $35 or below."

Legal and settlement

"Negotiate a settlement. The other party is asking $250,000. My ceiling is $180,000."

Any bilateral negotiation

"They're asking [X]. I won't pay more than [Y]. Negotiate."

Prerequisites

• Node.js 18+
• Claude Desktop or Claude Code
• A KLAVE API key — get one at klavecommerce.com

Install in Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "klave": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://klave1-production.up.railway.app/mcp/sse",
        "--header",
        "x-api-key:YOUR_API_KEY"
      ]
    }
  }
}

Replace YOUR_API_KEY with your key from klavecommerce.com.

Install in Claude Code

claude mcp add klave \
  --transport sse \
  "https://klave1-production.up.railway.app/mcp/sse" \
  --header "x-api-key:YOUR_API_KEY"

Run locally (stdio)

git clone https://github.com/juny-klave/klave-mcp.git
cd klave-mcp
npm install
npm run build

Then point Claude Desktop at the local build:

{
  "mcpServers": {
    "klave": {
      "command": "node",
      "args": ["/absolute/path/to/klave-mcp/dist/index.js"],
      "env": {
        "KLAVE_API_URL": "https://klave1-production.up.railway.app",
        "KLAVE_API_KEY": "YOUR_API_KEY"
      }
    }
  }
}

The 4 tools

| Tool | What it does | |---|---| | klave_negotiate | Start a negotiation — any subject, any industry, any price range | | klave_advance | Advance one round — call in a loop until SETTLED or TERMINATED | | klave_status | Get current state and full round history at any time | | klave_verify | Get the ZK proof confirming the settlement was conducted fairly |

Tool sequence

klave_negotiate        ← describe what you're negotiating and your ceiling
klave_advance (loop)   ← advance round by round until SETTLED
klave_status           ← check progress at any time
klave_verify           ← get cryptographic proof after settlement

Privacy guarantees

• Your ceiling (ceiling_price) is passed to the negotiation engine and never appears in any tool response.
• The seller's floor price is derived server-side and never a field in any API response.
• leaks_detected in verify responses is sourced from the server — never hardcoded.
• Every negotiation generates an auditable ZK proof.

Environment variables (local mode)

| Variable | Default | Description | |---|---|---| | KLAVE_API_URL | https://klave1-production.up.railway.app | KLAVE REST API base URL | | KLAVE_API_KEY | (empty) | API key | | TRANSPORT | stdio | stdio (Claude Desktop/Code) or http (remote/SSE) | | PORT | 3002 | HTTP port when TRANSPORT=http |

Getting an API key

Sign up at klavecommerce.com/docs.

Developer SDK

If you're building an agent that needs to authorize negotiation programmatically, see the KLAVE SDK (@juny-klave/sdk).

License

MIT