summarize_transcript

Implementation Reference

• src/modules/transcript-summarizer.js:12-59 (handler)

  Core handler function that executes the transcript summarization using OpenAI API, handling truncation and prompt engineering.

  export async function summarizeTranscript(transcript, tone, audience, wordCount, apiKey) {
    if (!apiKey) {
      throw new Error("OpenAI API key not provided");
    }
    
    if (!transcript || transcript.trim().length === 0) {
      throw new Error("Empty transcript provided");
    }
    
    console.log(`Summarizing transcript (${transcript.length} chars) with tone: ${tone}, audience: ${audience}`);
    
    try {
      // Initialize OpenAI client with provided API key
      const openai = new OpenAI({
        apiKey: apiKey,
      });
      
      // Truncate transcript if it's too long (to fit within token limits)
      const truncatedTranscript = truncateText(transcript, 15000);
      
      const response = await openai.chat.completions.create({
        model: "gpt-3.5-turbo",
        messages: [
          {
            role: "system",
            content: `You are a professional content summarizer. Summarize the provided transcript in a ${tone} tone for a ${audience} audience. 
            The summary should be approximately ${wordCount} words and capture the key points, insights, and valuable information from the transcript.
            Focus on making the summary concise, informative, and engaging.`
          },
          {
            role: "user",
            content: `Please summarize the following video transcript:\n\n${truncatedTranscript}`
          }
        ],
        temperature: 0.7,
        max_tokens: 500
      });
      
      if (response.choices && response.choices.length > 0) {
        return response.choices[0].message.content.trim();
      } else {
        throw new Error("No summary generated");
      }
    } catch (error) {
      console.error("Summarization error:", error);
      throw new Error(`Failed to summarize transcript: ${error.message}`);
    }
  }

• src/server.js:113-164 (registration)

  MCP tool registration for 'summarize_transcript', including input schema, handler wrapper, and description.

  server.tool(
    "summarize_transcript",
    { 
      transcript: z.string().describe("Video transcript text"),
      tone: z.enum(["educational", "inspirational", "professional", "conversational"])
        .default("professional")
        .describe("Tone of the summary"),
      audience: z.enum(["general", "technical", "business", "academic"])
        .default("general")
        .describe("Target audience for the summary"),
      wordCount: z.number().min(100).max(300).default(200)
        .describe("Approximate word count for the summary")
    },
    async ({ transcript, tone, audience, wordCount }) => {
      try {
        // Check if OpenAI API key is set
        if (!apiKeyManager.hasOpenAIKey()) {
          throw new Error("OpenAI API key not set. Please use the set_api_keys tool first.");
        }
        
        const summary = await summarizeTranscript(
          transcript, 
          tone, 
          audience, 
          wordCount, 
          apiKeyManager.getOpenAIKey()
        );
        
        return {
          content: [{ 
            type: "text", 
            text: JSON.stringify({
              success: true,
              summary
            }, null, 2)
          }]
        };
      } catch (error) {
        return {
          content: [{ 
            type: "text", 
            text: JSON.stringify({
              success: false,
              error: error.message
            }, null, 2)
          }],
          isError: true
        };
      }
    },
    { description: "Summarize a video transcript" }
  );

• src/server.js:115-125 (schema)

  Zod input schema defining parameters for the summarize_transcript tool.

  { 
    transcript: z.string().describe("Video transcript text"),
    tone: z.enum(["educational", "inspirational", "professional", "conversational"])
      .default("professional")
      .describe("Tone of the summary"),
    audience: z.enum(["general", "technical", "business", "academic"])
      .default("general")
      .describe("Target audience for the summary"),
    wordCount: z.number().min(100).max(300).default(200)
      .describe("Approximate word count for the summary")
  },

• src/modules/transcript-summarizer.js:61-79 (helper)

  Helper function to truncate long transcripts to fit token limits, used in the handler.

  /**
   * Truncate text to a maximum character length
   * @param {string} text - Text to truncate
   * @param {number} maxLength - Maximum length in characters
   * @returns {string} - Truncated text
   */
  function truncateText(text, maxLength) {
    if (text.length <= maxLength) return text;
    
    // Try to truncate at a sentence boundary
    const truncated = text.substring(0, maxLength);
    const lastPeriod = truncated.lastIndexOf('.');
    
    if (lastPeriod > maxLength * 0.8) {
      return truncated.substring(0, lastPeriod + 1);
    }
    
    return truncated + "...";
  }