# Hmac Generate — MCP tool `findutils:hmac_generate`

Compute an HMAC of a message with a secret key. Returns hex digest.

- Category: encoding
- MCP server: https://mcp.findutils.com/ (Streamable HTTP, no API keys, 120 req/min per IP)
- REST endpoint: POST https://api.findutils.com/api/tools/hmac-generate/execute (no API keys, 60 req/min per IP)
- Reference page: https://findutils.com/mcp/hmac-generate/
- Same tool on the other surface: https://findutils.com/api/hmac-generate/

## Connect

```bash
claude mcp add findutils --transport http https://mcp.findutils.com/
```

Claude Desktop (`claude_desktop_config.json`):

```json
{
  "mcpServers": {
    "findutils": {
      "url": "https://mcp.findutils.com/"
    }
  }
}
```

## Call the tool (verified example)

```bash
curl -X POST https://mcp.findutils.com/ \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/call",
    "params": {
      "name": "hmac_generate",
      "arguments": {
        "message": "hi",
        "secret": "k",
        "algorithm": "SHA-256"
      }
    }
  }'
```

## Input schema

| Argument | Type | Required | Description |
|---|---|---|---|
| `message` | string | yes | The message to authenticate. |
| `secret` | string | yes | The secret key. |
| `algorithm` | string (SHA-256 \| SHA-512) | no | HMAC algorithm. Defaults to SHA-256. Default: `"SHA-256"`. |

Example arguments (verified):

```json
{
  "message": "hi",
  "secret": "k",
  "algorithm": "SHA-256"
}
```

## Also a REST endpoint

```bash
curl -X POST https://api.findutils.com/api/tools/hmac-generate/execute \
  -H "Content-Type: application/json" \
  -d '{
    "message": "hi",
    "secret": "k",
    "algorithm": "SHA-256"
  }'

# Parameter schema
curl https://api.findutils.com/api/tools/hmac-generate
```

Full REST reference: https://findutils.com/api/hmac-generate/ · OpenAPI 3.1 spec: https://findutils.com/api/openapi.json

---
Full catalog: POST https://mcp.findutils.com/ with method `tools/list` · https://findutils.com/mcp/ · https://findutils.com/llms.txt