# Hono MCP (Model Context Protocol)

Connect Hono to a Model Context Protocol (MCP) server over HTTP Streaming Transport.

## Streamable HTTP Transport

```ts
import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
import { StreamableHTTPTransport } from '@hono/mcp'
import { Hono } from 'hono'

const app = new Hono()

// Your MCP server implementation
const mcpServer = new McpServer({
  name: 'my-mcp-server',
  version: '1.0.0',
})

// Initialize the transport
const transport = new StreamableHTTPTransport()

app.all('/mcp', async (c) => {
  if (!mcpServer.isConnected()) {
    // Connect the mcp with the transport
    await mcpServer.connect(transport)
  }

  return transport.handleRequest(c)
})

export default app
```

## Auth

The simplest way to setup MCP Auth when using 3rd party auth providers.

```ts
import { Hono } from 'hono'
import { simpleMcpAuthRouter } from '@hono/mcp'

const app = new Hono()

app.route(
  '/',
  simpleMcpAuthRouter({
    issuer: '[auth provider domain]',
    resourceServerUrl: new URL('http://localhost:3000/mcp'),
  })
)

// ...
// Logic to connect with the transport
```

For implementing custom auth, check out the docs - <https://honohub.dev/docs/hono-mcp>

## Author

Aditya Mathur <https://github.com/mathuraditya724>

## License

MIT


Supply Chain Attack on Axios Pulls Malicious Dependency from npm

@hono/mcp

yusukebe

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Bad semver

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Bad dependency semver

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Bidirectional unicode control characters

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Bin script confusion

This Chrome extension includes content scripts that execute JavaScript on specified websites.

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Chrome: Content Script

This Chrome extension requests host permissions to access specific websites or domains.

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Chrome: Host Permission

This Chrome extension requests permissions to access browser APIs, user data, or system features.

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This Chrome extension requests wildcard host permissions that grant broad access to websites.

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Chrome: Wildcard Host Permission

Semantic versions published out of chronological order.

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Chronological version anomaly

Project maintainer's SSH key has been compromised.

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Compromised SSH key

What do I need to know about license files?

Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

What is a critical CVE?

Title

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Contains a high severity Common Vulnerability and Exposure (CVE).

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High CVE

Uses debug, reflection and dynamic code execution features.

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Debug access

The maintainer of the package marked it as deprecated. This could indicate that a single version should not be used, or that the package is no longer maintained and any new vulnerabilities will not be fixed.

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Deprecated

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Possible typosquat attack

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Dynamic require

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Empty package

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File dependency

Accesses the file system, and could potentially read sensitive data.

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Filesystem access

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Wildcard dependency

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An input argument to this GitHub Action is being passed back as an output. If a user of this action passes untrusted input, it could be used in an insecure manner by consuming workflows.

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An input argument to this GitHub Action flows into a dangerous sink (such as shell command execution). This could allow a malicious user to inject commands or exploit the action.

GitHub Actions: Input argument flows to dangerous sink

A GitHub context variable (such as issue title, PR description, or comment body) is being exported as an environment variable. These context values are user-controlled and could be exploited by subsequent workflow steps.

GitHub Actions: GitHub context variable exported as environment variable

A GitHub context variable (such as issue title, PR description, or comment body) is being passed back as an output. These context values are user-controlled and could be exploited by consuming workflows.

GitHub Actions: GitHub context variable passed back as output

A GitHub context variable (such as issue title, PR description, or comment body) flows into a dangerous sink (such as shell command execution). This is a critical security issue that could allow command injection or code execution attacks.

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An environment variable flows into a dangerous sink (such as shell command execution). If this environment variable comes from an untrusted source, it could be exploited to inject commands.

GitHub Actions: Environment variable flows to dangerous sink

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Git dependency

Contains a dependency which resolves to a GitHub URL. Dependencies fetched from GitHub specifiers are not immutable can be used to inject untrusted code or reduce the likelihood of a reproducible install.

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GitHub dependency

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AI-detected potential code anomaly

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AI-detected possible typosquat

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AI-detected potential malware

AI has determined that this package may contain potential security issues or vulnerabilities.

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AI-detected potential security risk

Contains native code (e.g., compiled binaries or shared libraries). Including native code can obscure malicious behavior.

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Contains a dependency which resolves to a remote HTTP URL which could be used to inject untrusted code and reduce overall package reliability.

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Network access

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

@hono/mcp

Hono MCP (Model Context Protocol)

Streamable HTTP Transport

Auth

Author

License

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