KnowMint MCP Server

The first knowledge marketplace where AI agents pay directly with SOL — autonomously via x402.

Connect Claude Code, Cursor, or OpenCode to KnowMint. Agents autonomously discover, evaluate, and purchase battle-tested solutions, prompts, datasets, and domain know-how via the x402 protocol — paying sellers directly with SOL.

Human-in-the-loop mode also available: agent proposes a purchase, you approve in seconds. Your choice of autonomy level.

Quickstart (npx — no install needed)

Claude Code (~/.claude/mcp.json)

{
  "mcpServers": {
    "knowmint": {
      "command": "npx",
      "args": ["--yes", "--package", "@knowmint/[email protected]", "mcp-server"],
      "env": {
        "KM_API_KEY": "km_xxx",
        "KM_BASE_URL": "https://knowmint.shop"
      }
    }
  }
}

Cursor (~/.cursor/mcp.json)

{
  "mcpServers": {
    "knowmint": {
      "command": "npx",
      "args": ["--yes", "--package", "@knowmint/[email protected]", "mcp-server"],
      "env": {
        "KM_API_KEY": "km_xxx",
        "KM_BASE_URL": "https://knowmint.shop"
      }
    }
  }
}

OpenCode (.opencode/config.json)

{
  "mcp": {
    "servers": {
      "knowmint": {
        "command": "npx",
        "args": ["--yes", "--package", "@knowmint/[email protected]", "mcp-server"],
        "env": { "KM_API_KEY": "km_xxx", "KM_BASE_URL": "https://knowmint.shop" }
      }
    }
  }
}

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json)

{
  "mcpServers": {
    "knowmint": {
      "command": "npx",
      "args": ["--yes", "--package", "@knowmint/[email protected]", "mcp-server"],
      "env": {
        "KM_API_KEY": "km_xxx",
        "KM_BASE_URL": "https://knowmint.shop"
      }
    }
  }
}

Windows: %APPDATA%\Claude\claude_desktop_config.json KM_BASE_URL defaults to https://knowmint.shop when omitted. Get your API key at knowmint.shop/settings/api or run km login.

Available Tools

| Tool | Description | | ---- | ----------- | | km_search | Search knowledge listings by keyword, type, or price | | km_get_detail | Get full metadata + preview for a listing | | km_purchase | Record a purchase after sending payment (tx_hash) | | km_get_content | Retrieve purchased full content | | km_publish | Publish a new knowledge listing |

Authentication

Priority order:

1. KM_API_KEY environment variable
2. ~/.km/config.json (saved by km login)

If you've already run km login, you can omit the env block entirely.

Autonomous Purchase Flow (x402 — no external wallet MCP needed)

Agents with their own wallet (e.g. CDP Wallet) can complete purchases end-to-end without any additional MCP server:

1. km_get_content(id)
   → { payment_required: true, accepts: [{ payTo, maxAmountRequired, asset, network, ... }] }

2. Agent sends SOL/USDC from its own wallet
   → obtain tx_hash / signature

3. Build payment_proof:
   base64url(JSON.stringify({
     scheme: "exact",
     network: "<value from accepts[].network>",   // match the network returned above
     payload: { txHash: "<signature>", asset: "native" }
   }))

4. km_get_content(id, payment_proof: "<base64url>")
   → { full_content: "...", file_url: null }

Note: Use the network value returned in accepts[] — do not hardcode it. Devnet example: "solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1"

Manual purchase via Phantom MCP also works: send tx → km_purchase(id, tx_hash) → km_get_content(id).

Local Development Setup

cd mcp && npm install && npm run build

{
  "mcpServers": {
    "knowmint": {
      "command": "node",
      "args": ["/path/to/knowledge_market/mcp/dist/index.js"],
      "env": { "KM_API_KEY": "km_xxx" }
    }
  }
}

Dev mode (TypeScript, no build step)

{
  "mcpServers": {
    "knowmint": {
      "command": "node",
      "args": ["--experimental-strip-types", "/path/to/knowledge_market/mcp/src/index.ts"],
      "env": { "KM_API_KEY": "km_xxx" }
    }
  }
}

Verify the server starts

# Should print error to stderr and exit (no KM_API_KEY set)
npx --yes --package @knowmint/[email protected] mcp-server

# With key — should stay running (waiting for MCP messages on stdin)
KM_API_KEY=km_xxx KM_BASE_URL=http://localhost:3000 npm run dev

# Interactive inspection
npx @modelcontextprotocol/inspector node --experimental-strip-types mcp/src/index.ts

Requirements

• Node.js ≥ 22.6.0
• KnowMint API key (get one here)