list_credentials

Instructions

Implementation Reference

• src/tools/handler.ts:165-177 (handler)

  The handler case in ToolHandler.handleTool that processes 'list_credentials' tool calls by delegating to N8nManager.listCredentials() and formatting the response as MCP content.

  case 'list_credentials':
    const credentials = await this.n8nManager.listCredentials();
    return {
      content: [{
        type: 'text',
        text: credentials.length > 0
          ? `📋 Found ${credentials.length} credentials in n8n:\n\n` +
            credentials.map((c: any) => `• ID: ${c.id}\n  Name: ${c.name}\n  Type: ${c.type}`).join('\n\n') +
            '\n\n💡 Use these IDs in your workflow nodes to reference credentials'
          : '📭 No credentials found in n8n\n\n' +
            '💡 Add credentials in the n8n UI first, then use this command to get their IDs'
      }]
    };

• src/n8n/manager.ts:652-763 (helper)

  Core implementation in N8nManager that executes n8n CLI commands to list credentials, parses table/JSON output, falls back to API, and handles errors.

  async listCredentials(): Promise<any> {
    try {
      // Try different credential listing approaches
      // First try the credentials list command
      let command = 'n8n credential:list';
      console.error(`Executing: ${command}`);
  
      let stdout: string;
      let stderr: string;
  
      try {
        ({ stdout, stderr } = await execAsync(command, {
          timeout: 10000,
        }));
      } catch (error: any) {
        // If that fails, try alternative command
        console.error('credential:list failed, trying list:credential');
        command = 'n8n list:credential';
        try {
          ({ stdout, stderr } = await execAsync(command, {
            timeout: 10000,
          }));
        } catch (error2: any) {
          // If both fail, provide helpful message
          throw new Error(
            'Unable to list credentials via n8n CLI. ' +
            'Please check credentials manually in n8n UI at http://localhost:5678/credentials'
          );
        }
      }
  
      if (this.hasRealError(stderr, stdout)) {
        throw new Error(stderr);
      }
  
      // Parse the output - n8n outputs credentials as a table or JSON
      const lines = stdout.split('\n').filter(line => line.trim());
      const credentials: Array<{id: string, name: string, type: string}> = [];
  
      // Try to parse as JSON first
      try {
        const parsed = JSON.parse(stdout);
        if (Array.isArray(parsed)) {
          return parsed;
        }
      } catch {
        // Not JSON, parse as table
        // Skip header lines, typically starts with "ID" or similar
        let inData = false;
        for (const line of lines) {
          if (line.includes('ID') && line.includes('Name')) {
            inData = true;
            continue;
          }
          if (inData && line.trim()) {
            // Parse table row - format is typically: ID | Name | Type | ...
            const parts = line.split(/\s{2,}|\t|\|/).map(s => s.trim()).filter(s => s);
            if (parts.length >= 2) {
              credentials.push({
                id: parts[0],
                name: parts[1],
                type: parts[2] || 'unknown'
              });
            }
          }
        }
      }
  
      return credentials;
    } catch (error: any) {
      // If CLI doesn't work, try using the API
      console.error('CLI approach failed, trying API approach');
  
      try {
        // Use curl to access n8n API (if available)
        const apiCommand = 'curl -s http://localhost:5678/rest/credentials';
        const { stdout: apiOutput } = await execAsync(apiCommand, {
          timeout: 5000,
        });
  
        const apiCredentials = JSON.parse(apiOutput);
        if (Array.isArray(apiCredentials.data)) {
          return apiCredentials.data.map((cred: any) => ({
            id: cred.id,
            name: cred.name,
            type: cred.type
          }));
        }
      } catch (apiError) {
        console.error('API approach also failed');
      }
  
      // If n8n is not running or command fails
      if (error.message.includes('command not found')) {
        throw new Error('n8n CLI is not installed');
      }
      if (error.message.includes('connect')) {
        throw new Error('n8n is not running. Start it with: n8n start');
      }
  
      // Return informative error
      throw new Error(
        'Unable to list credentials. The n8n CLI may not support this command. ' +
        'Please check your credentials manually in the n8n UI at http://localhost:5678/credentials\n\n' +
        'To find credential IDs:\n' +
        '1. Open n8n UI\n' +
        '2. Go to Credentials\n' +
        '3. Click on a credential\n' +
        '4. The ID is in the URL (e.g., /credentials/ABC123xyz/edit)'
      );
    }
  }

• src/tools/registry.ts:297-304 (registration)

  Tool registration in getToolDefinitions() array, including name, description, and input schema (empty object).

  {
    name: 'list_credentials',
    description: 'List all credentials in n8n with their IDs - use these IDs in workflow nodes',
    inputSchema: {
      type: 'object',
      properties: {},
    },
  },

• src/tools/registry.ts:300-303 (schema)

  Input schema definition for the tool (no required properties).

  inputSchema: {
    type: 'object',
    properties: {},
  },