Hashing MCP Server with SHA-256 and MD5

Overview

This MCP (Model Context Protocol) hashing server provides a lightweight HTTP service for generating checksums and cryptographic hashes using SHA-256 and MD5. It is designed to sit alongside model-serving or data-processing components and produce fast, reproducible digests of payloads for integrity checks, deduplication, audit logs, and lightweight verification in distributed systems.

Hashing at the MCP layer is useful when you want to avoid transmitting or storing raw sensitive data (such as financial records or personally identifiable information) while retaining a verifiable representation. SHA-256 offers strong integrity guarantees suitable for tamper-evidence, and MD5 provides a very fast checksum for non-security uses such as quick deduplication or compatibility with legacy systems.

Features

• HTTP API for on-demand hash generation
• Support for SHA-256 and MD5 output formats (hex and base64)
• Small footprint suitable for containerized deployment
• Optional configuration for port, allowed algorithms, and logging
• Examples for curl, Python, and Node.js clients
• Useful for integrity checks, deduplication, and audit trails in finance workflows

Installation / Configuration

Clone the repository and run with Docker (recommended) or build locally.

Docker:

git clone https://github.com/kanad13/MCP-Server-for-Hashing.git
cd MCP-Server-for-Hashing
docker build -t mcp-hashing .
docker run -p 8080:8080 --env PORT=8080 mcp-hashing

Local build (if the project is implemented in Go or a compiled language):

git clone https://github.com/kanad13/MCP-Server-for-Hashing.git
cd MCP-Server-for-Hashing
# Example for Go-based project
go build -o mcp-hashing ./cmd/server
./mcp-hashing --port 8080

Example configuration file (config.json):

{
  "port": 8080,
  "allowed_algorithms": ["sha256", "md5"],
  "log_level": "info",
  "max_payload_bytes": 1048576
}

Environment variables (common options):

• PORT — HTTP port (default 8080)
• LOG_LEVEL — log verbosity (debug/info/warn/error)
• ALLOWED_ALGORITHMS — comma-separated list (e.g. “sha256,md5”)
• MAX_PAYLOAD_BYTES — limit on request body size

API (example)

POST /hash Request:

POST /hash HTTP/1.1
Content-Type: application/json

{
  "algorithm": "sha256",
  "format": "hex",        // "hex" or "base64"
  "data": "hello world"   // raw text or base64-encoded binary
}

Response:

{
  "algorithm": "sha256",
  "format": "hex",
  "digest": "a948904f2f0f479b8f8197694b30184b0d2e42e4f..."
}

Example curl (SHA-256 hex):

curl -sS -X POST http://localhost:8080/hash \
  -H "Content-Type: application/json" \
  -d '{"algorithm":"sha256","format":"hex","data":"hello world"}'

Available Tools / Resources

• CLI: curl for quick ad-hoc checks
• Verification tools: sha256sum and md5sum on Unix-like systems
• SDK examples: small Python and Node.js snippets for integrating with the API

Python example:

import requests
resp = requests.post("http://localhost:8080/hash", json={
    "algorithm": "sha256",
    "format": "hex",
    "data": "hello world"
})
print(resp.json()["digest"])

Node.js example:

const fetch = require('node-fetch');
(async () => {
  const r = await fetch('http://localhost:8080/hash', {
    method: 'POST',
    headers: {'Content-Type':'application/json'},
    body: JSON.stringify({algorithm: 'md5', format: 'hex', data: 'file content'})
  });
  console.log(await r.json());
})();

Supported algorithms (typical):

Use Cases

• Financial record integrity: Generate SHA-256 hashes of transaction batches to store in an audit log separate from raw records. This creates an immutable reference you can later verify without exposing sensitive fields.
• Fast deduplication: Use MD5 checksums for quick identification of duplicate files or messages in ingestion pipelines where collision risk is acceptable.
• Inter-service verification: Microservices can exchange digest values instead of entire payloads to confirm consistency after transmission, reducing bandwidth and storage.
• Offline verification: Produce hash manifests for nightly exports so auditors can verify that datasets were unchanged using standard tools (sha256sum / md5sum).
• Privacy-preserving telemetry: Store hashes of personally identifiable strings for analytics correlation without storing the cleartext values.

Best Practices

• Prefer SHA-256 for any security-critical use. Reserve MD5 for non-security checks where speed or legacy compatibility matters.
• Limit payload size and validate input to avoid denial-of-service risks.
• Use HTTPS in production to protect data-in-transit when sending sensitive payloads for hashing.
• Log only metadata (algorithm, size, request ID) and avoid logging raw data to protect privacy and maintain compliance in finance contexts.

This MCP hashing server provides a simple, auditable way to generate and verify digests tailored to data-intensive and privacy-sensitive workflows.