Feature: Add get_call_transcript Tool

CHANGELOG.md

@@ -0,0 +1,6 @@
+# Changelog
+
+## [Unreleased]
+### Enhanced
+- Improved message transformation in CallTranscriptOutput to handle optional properties
+- Enhanced type safety for message handling

README.md

@@ -225,6 +225,7 @@ The Vapi MCP Server provides the following tools for integration:
   - Immediate or scheduled calls
   - Dynamic variable values through `assistantOverrides`
 - `get_call`: Gets details of a specific call
+- `get_call_transcript`: Gets the full transcript and conversation data of a specific call
 
 > **Note:** The `create_call` action supports scheduling calls for immediate execution or for a future time. You can also pass dynamic variables using `assistantOverrides.variableValues` to personalize assistant messages.
 

src/schemas/index.ts

@@ -304,6 +304,21 @@ export const GetCallInputSchema = z.object({
   callId: z.string().describe('ID of the call to get'),
 });
 
+export const CallTranscriptOutputSchema = BaseResponseSchema.extend({
+  id: z.string(),
+  transcript: z.string().optional(),
+  messages: z.array(z.object({
+    role: z.string(),
+    message: z.string().optional(),
+    time: z.number().optional(),
+    duration: z.number().optional(),
+  })).optional(),
+  recordingUrl: z.string().optional(),
+  summary: z.string().optional(),
+});
+
+export const GetCallTranscriptInputSchema = GetCallInputSchema;
+
 // ===== Phone Number Schemas =====
 
 export const GetPhoneNumberInputSchema = z.object({

src/tools/call.ts

@@ -1,10 +1,11 @@
 import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
 import { VapiClient, Vapi } from '@vapi-ai/server-sdk';
 
-import { CallInputSchema, GetCallInputSchema } from '../schemas/index.js';
+import { CallInputSchema, GetCallInputSchema, GetCallTranscriptInputSchema } from '../schemas/index.js';
 import {
   transformCallInput,
   transformCallOutput,
+  transformCallTranscriptOutput,
 } from '../transformers/index.js';
 import { createToolHandler } from './utils.js';
 
@@ -42,4 +43,14 @@ export const registerCallTools = (
       return transformCallOutput(call);
     })
   );
+
+  server.tool(
+    'get_call_transcript',
+    'Gets the full transcript and conversation data of a specific call',
+    GetCallTranscriptInputSchema.shape,
+    createToolHandler(async (data) => {
+      const call = await vapiClient.calls.get(data.callId);
+      return transformCallTranscriptOutput(call);
+    })
+  );
 };

src/transformers/index.ts

@@ -5,6 +5,7 @@ import {
   CallInputSchema,
   AssistantOutputSchema,
   CallOutputSchema,
+  CallTranscriptOutputSchema,
   PhoneNumberOutputSchema,
   ToolOutputSchema,
   UpdateAssistantInputSchema,
@@ -228,6 +229,44 @@ export function transformCallOutput(
   };
 }
 
+export function transformCallTranscriptOutput(
+  call: Vapi.Call
+): z.infer<typeof CallTranscriptOutputSchema> {
+  return {
+    id: call.id,
+    createdAt: call.createdAt,
+    updatedAt: call.updatedAt,
+    transcript: call.artifact?.transcript,
+    messages: call.artifact?.messages?.map(msg => {
+      // Handle different message types safely
+      const transformedMessage: any = {
+        role: msg.role,
+        time: msg.time || 0,
+      };
+
+      // Check if message has a 'message' property (UserMessage, BotMessage, SystemMessage, ToolCallMessage)
+      if ('message' in msg && typeof msg.message === 'string') {
+        transformedMessage.message = msg.message;
+      } else if ('result' in msg && typeof msg.result === 'string') {
+        // For ToolCallResultMessage, use result as message
+        transformedMessage.message = msg.result;
+      } else {
+        // Fallback for unknown message types - set to undefined since schema allows optional
+        transformedMessage.message = undefined;
+      }
+
+      // Check if message has a 'duration' property (UserMessage, BotMessage)
+      if ('duration' in msg && typeof msg.duration === 'number') {
+        transformedMessage.duration = msg.duration;
+      }
+
+      return transformedMessage;
+    }),
+    recordingUrl: call.artifact?.recordingUrl,
+    summary: call.analysis?.summary,
+  };
+}
+
 // ===== Phone Number Transformers =====
 
 export function transformPhoneNumberOutput(