MCP SSH Server

Instructions

Implementation Reference

• src/index.ts:1127-1153 (handler)

  Handler function that parses empty input schema, retrieves all stored credentials from the in-memory Map, formats a safe list (hiding sensitive data like passwords/keys), and returns a text response listing available credentials with metadata.

  private async handleListCredentials(args: unknown) {
    ListCredentialsSchema.parse(args);
    
    const credentials = Array.from(credentialStore.entries()).map(([id, cred]) => ({
      credentialId: id,
      host: cred.host,
      port: cred.port,
      username: cred.username,
      hasPassword: !!cred.password,
      hasPrivateKey: !!cred.privateKeyPath,
      createdAt: cred.createdAt,
      lastUsed: cred.lastUsed
    }));
  
    return {
      content: [
        {
          type: 'text',
          text: credentials.length > 0 
            ? `Saved credentials:\n${credentials.map(c => 
                `- ${c.credentialId}: ${c.username}@${c.host}:${c.port} (${c.hasPassword ? 'password' : 'key'}) - Last used: ${c.lastUsed}`
              ).join('\n')}`
            : 'No saved credentials found',
        },
      ],
    };
  }

• src/index.ts:137-138 (schema)

  Zod schema for tool input validation. Defines an empty object since the tool requires no parameters.

  const ListCredentialsSchema = z.object({});

• src/index.ts:388-396 (registration)

  Tool metadata registration in the ListToolsRequestHandler response. Specifies the tool name, description, and JSON input schema advertised to clients.

  {
    name: 'ssh_list_credentials',
    description: 'List all saved SSH credentials',
    inputSchema: {
      type: 'object',
      properties: {},
      required: []
    },
  },

• src/index.ts:507-508 (registration)

  Dispatch registration in the CallToolRequestHandler switch statement, mapping tool name to the handler method.

  case 'ssh_list_credentials':
    return await this.handleListCredentials(args);

• src/index.ts:46-47 (helper)

  In-memory Map storing SSH credentials by ID, used by the handler to list credentials. Defined globally in the module.

  const credentialStore = new Map<string, StoredCredential>();