Excel MCP Server

Instructions

Implementation Reference

• src/index.ts:1261-1263 (registration)

  Dispatch registration in the CallToolRequestSchema handler that routes 'explain_formula' tool calls to AIOperationsHandler.explainFormula

  case 'explain_formula':
    return await this.aiOpsHandler.explainFormula(toolArgs);
  case 'ai_provider_status':

• src/index.ts:884-901 (schema)

  Tool schema definition including input schema with required 'formula' parameter and optional AI 'provider'

    name: 'explain_formula',
    description: 'Explain what an Excel formula does in plain English',
    inputSchema: {
      type: 'object',
      properties: {
        formula: {
          type: 'string',
          description: 'Excel formula to explain (e.g., "=VLOOKUP(A2,B:C,2,FALSE)")',
        },
        provider: {
          type: 'string',
          description: 'Preferred AI provider: anthropic, openai, deepseek, gemini, or local (optional)',
          enum: ['anthropic', 'openai', 'deepseek', 'gemini', 'local'],
        },
      },
      required: ['formula'],
    },
  },

• src/handlers/ai-operations.ts:196-229 (handler)

  Main handler function that extracts arguments, delegates to NLPProcessor.explainFormula, formats response as MCP ToolResponse

  async explainFormula(args: ToolArgs): Promise<ToolResponse> {
    const { formula, provider } = args;
  
    try {
      const explanation = await this.nlpProcessor.explainFormula(formula, provider);
  
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              formula,
              explanation,
              success: true,
              provider: this.nlpProcessor.getActiveProvider()?.name || 'Local'
            }, null, 2),
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify({
              formula,
              error: error instanceof Error ? error.message : 'Unknown error',
              success: false
            }, null, 2),
          },
        ],
      };
    }
  }

• src/ai/nlp-processor.ts:94-111 (helper)

  Core helper function in NLPProcessor that generates AI prompt for formula explanation, calls AIManager for completion, with fallback explainer

  async explainFormula(formula: string, preferredProvider?: ProviderType): Promise<string> {
    const prompt = `Explain this Excel formula in simple terms: ${formula}`;
    
    try {
      const response = await this.aiManager.createCompletion([
        { role: 'user', content: prompt }
      ], {
        maxTokens: 300,
        temperature: 0,
        preferredProvider
      });
  
      return response.content;
    } catch (error) {
      // console.error('Error explaining formula:', error);
      return this.fallbackFormulaExplainer(formula);
    }
  }