PowerShell MCP Server

Implementation Reference

• src/index.ts:193-256 (handler)

  Handler function that retrieves detailed help for a PowerShell command using Get-Help -Full, structures the output as JSON, executes via powershell command, and returns markdown content or error.

  async ({ command }: { command: string }) => {
    try {
      const psCommand = `
        $Help = Get-Help ${command} -Full
        $Output = [PSCustomObject]@{
          Name = $Help.Name
          Synopsis = $Help.Synopsis
          Syntax = $Help.Syntax | Out-String
          Description = $Help.Description | Out-String
          Parameters = $Help.Parameters.Parameter | ForEach-Object {
            [PSCustomObject]@{
              Name = $_.Name
              Type = $_.Type.Name
              Required = $_.Required
              Description = $_.Description | Out-String
            }
          }
          Examples = $Help.Examples.Example | ForEach-Object {
            [PSCustomObject]@{
              Title = $_.Title
              Code = $_.Code
              Remarks = $_.Remarks | Out-String
            }
          }
        }
        ConvertTo-Json -InputObject $Output -Depth 5
      `;
  
      const { stdout, stderr } = await execAsync(
        `powershell -Command "${psCommand.replace(/"/g, '\\"')}"`
      );
  
      if (stderr) {
        return {
          isError: true,
          content: [
            {
              type: 'text' as const,
              text: `Error retrieving help: ${stderr}`,
            },
          ],
        };
      }
  
      return {
        content: [
          {
            type: 'text' as const,
            text: stdout,
          },
        ],
      };
    } catch (error) {
      return {
        isError: true,
        content: [
          {
            type: 'text' as const,
            text: `Error retrieving help: ${(error as Error).message}`,
          },
        ],
      };
    }
  }

• src/index.ts:190-192 (schema)

  Input schema using Zod: requires a 'command' string parameter describing the PowerShell command to get help for.

  {
    command: z.string().describe('PowerShell command to get help for'),
  },

• src/index.ts:188-257 (registration)

  Tool registration call: this.server.tool('get_command_help', schema, handler) within the registerTools method.

  this.server.tool(
    'get_command_help',
    {
      command: z.string().describe('PowerShell command to get help for'),
    },
    async ({ command }: { command: string }) => {
      try {
        const psCommand = `
          $Help = Get-Help ${command} -Full
          $Output = [PSCustomObject]@{
            Name = $Help.Name
            Synopsis = $Help.Synopsis
            Syntax = $Help.Syntax | Out-String
            Description = $Help.Description | Out-String
            Parameters = $Help.Parameters.Parameter | ForEach-Object {
              [PSCustomObject]@{
                Name = $_.Name
                Type = $_.Type.Name
                Required = $_.Required
                Description = $_.Description | Out-String
              }
            }
            Examples = $Help.Examples.Example | ForEach-Object {
              [PSCustomObject]@{
                Title = $_.Title
                Code = $_.Code
                Remarks = $_.Remarks | Out-String
              }
            }
          }
          ConvertTo-Json -InputObject $Output -Depth 5
        `;
  
        const { stdout, stderr } = await execAsync(
          `powershell -Command "${psCommand.replace(/"/g, '\\"')}"`
        );
  
        if (stderr) {
          return {
            isError: true,
            content: [
              {
                type: 'text' as const,
                text: `Error retrieving help: ${stderr}`,
              },
            ],
          };
        }
  
        return {
          content: [
            {
              type: 'text' as const,
              text: stdout,
            },
          ],
        };
      } catch (error) {
        return {
          isError: true,
          content: [
            {
              type: 'text' as const,
              text: `Error retrieving help: ${(error as Error).message}`,
            },
          ],
        };
      }
    }
  );