ERPNext MCP Server

Instructions

Implementation Reference

• src/index.ts:610-667 (handler)

  Main execution logic for the 'get_doctype_fields' tool: authenticates, fetches a sample document using erpnext.getDocList, extracts field names, types, and samples from the first document, and returns them as JSON.

  case "get_doctype_fields": {
    if (!erpnext.isAuthenticated()) {
      return {
        content: [{
          type: "text",
          text: "Not authenticated with ERPNext. Please configure API key authentication."
        }],
        isError: true
      };
    }
    
    const doctype = String(request.params.arguments?.doctype);
    
    if (!doctype) {
      throw new McpError(
        ErrorCode.InvalidParams,
        "Doctype is required"
      );
    }
    
    try {
      // Get a sample document to understand the fields
      const documents = await erpnext.getDocList(doctype, {}, ["*"], 1);
      
      if (!documents || documents.length === 0) {
        return {
          content: [{
            type: "text",
            text: `No documents found for ${doctype}. Cannot determine fields.`
          }],
          isError: true
        };
      }
      
      // Extract field names from the first document
      const sampleDoc = documents[0];
      const fields = Object.keys(sampleDoc).map(field => ({
        fieldname: field,
        value: typeof sampleDoc[field],
        sample: sampleDoc[field]?.toString()?.substring(0, 50) || null
      }));
      
      return {
        content: [{
          type: "text",
          text: JSON.stringify(fields, null, 2)
        }]
      };
    } catch (error: any) {
      return {
        content: [{
          type: "text",
          text: `Failed to get fields for ${doctype}: ${error?.message || 'Unknown error'}`
        }],
        isError: true
      };
    }
  }

• src/index.ts:334-346 (schema)

  Input schema and metadata for the 'get_doctype_fields' tool, defining the required 'doctype' parameter.

    name: "get_doctype_fields",
    description: "Get fields list for a specific DocType",
    inputSchema: {
      type: "object",
      properties: {
        doctype: {
          type: "string",
          description: "ERPNext DocType (e.g., Customer, Item)"
        }
      },
        required: ["doctype"]
    }
  },