fix: address PR #49 review feedback

- Replace npx with pnpm dlx in CI actions for consistency
- Add type guard for safer response type checking
- Refactor IIFE patterns in getMessage/getText to private helper methods
- Add braces to single-line if statement for readability
- Add validation before assigning finalResponse

Author: mattapperson

.github/actions/validate-sdk/action.yaml

@@ -43,19 +43,24 @@ runs:
       working-directory: examples/nextjs-example
       run: npm install
 
+    - name: Setup pnpm
+      uses: pnpm/action-setup@v4
+      with:
+        version: 9
+
     - name: Typecheck nextjs-example
       shell: bash
       working-directory: examples/nextjs-example
-      run: npx tsc --noEmit
+      run: pnpm dlx tsc --noEmit
 
     - name: Run unit tests
       shell: bash
       env:
         OPENROUTER_API_KEY: ${{ inputs.openrouter-api-key }}
-      run: npx vitest --run --exclude 'tests/e2e/**'
+      run: pnpm dlx vitest --run --exclude 'tests/e2e/**'
 
     - name: Run e2e tests
       shell: bash
       env:
         OPENROUTER_API_KEY: ${{ inputs.openrouter-api-key }}
-      run: npx vitest --run tests/e2e/
+      run: pnpm dlx vitest --run tests/e2e/

src/lib/response-wrapper.ts

@@ -70,6 +70,20 @@ export class ResponseWrapper {
     this.options = options;
   }
 
+  /**
+   * Type guard to check if a value is a non-streaming response
+   */
+  private isNonStreamingResponse(value: unknown): value is models.OpenResponsesNonStreamingResponse {
+    return (
+      value !== null &&
+      typeof value === "object" &&
+      "id" in value &&
+      "object" in value &&
+      "output" in value &&
+      !("toReadableStream" in value)
+    );
+  }
+
   /**
    * Initialize the stream if not already started
    * This is idempotent - multiple calls will return the same promise
@@ -265,21 +279,60 @@ export class ResponseWrapper {
         const value = newResult.value;
         if (value && typeof value === "object" && "toReadableStream" in value) {
           // It's a stream, consume it
-          const stream = new ReusableReadableStream(value as EventStream<models.OpenResponsesStreamEvent>);
+          const streamValue = value as EventStream<models.OpenResponsesStreamEvent>;
+          const stream = new ReusableReadableStream(streamValue);
           currentResponse = await consumeStreamForCompletion(stream);
+        } else if (this.isNonStreamingResponse(value)) {
+          currentResponse = value;
         } else {
-          currentResponse = value as models.OpenResponsesNonStreamingResponse;
+          throw new Error("Unexpected response type from API");
         }
 
         currentRound++;
       }
 
+      // Validate the final response has required fields
+      if (!currentResponse || !currentResponse.id || !currentResponse.output) {
+        throw new Error("Invalid final response: missing required fields");
+      }
+
+      // Ensure the response is in a completed state (has output content)
+      if (!Array.isArray(currentResponse.output) || currentResponse.output.length === 0) {
+        throw new Error("Invalid final response: empty or invalid output");
+      }
+
       this.finalResponse = currentResponse;
     })();
 
     return this.toolExecutionPromise;
   }
 
+  /**
+   * Internal helper to get the message after tool execution
+   */
+  private async getMessageInternal(): Promise<models.AssistantMessage> {
+    await this.executeToolsIfNeeded();
+
+    if (!this.finalResponse) {
+      throw new Error("Response not available");
+    }
+
+    return extractMessageFromResponse(this.finalResponse);
+  }
+
+  /**
+   * Internal helper to get the text after tool execution
+   */
+  private async getTextInternal(): Promise<string> {
+    await this.executeToolsIfNeeded();
+
+    if (!this.finalResponse) {
+      throw new Error("Response not available");
+    }
+
+    return extractTextFromResponse(this.finalResponse);
+  }
+
   /**
    * Get the completed message from the response.
    * This will consume the stream until completion, execute any tools, and extract the first message.
@@ -290,16 +343,7 @@ export class ResponseWrapper {
       return this.messagePromise;
     }
 
-    this.messagePromise = (async (): Promise<models.AssistantMessage> => {
-      await this.executeToolsIfNeeded();
-
-      if (!this.finalResponse) {
-        throw new Error("Response not available");
-      }
-
-      return extractMessageFromResponse(this.finalResponse);
-    })();
-
+    this.messagePromise = this.getMessageInternal();
     return this.messagePromise;
   }
 
@@ -312,16 +356,7 @@ export class ResponseWrapper {
       return this.textPromise;
     }
 
-    this.textPromise = (async () => {
-      await this.executeToolsIfNeeded();
-
-      if (!this.finalResponse) {
-        throw new Error("Response not available");
-      }
-
-      return extractTextFromResponse(this.finalResponse);
-    })();
-
+    this.textPromise = this.getTextInternal();
     return this.textPromise;
   }
 
@@ -501,7 +536,9 @@ export class ResponseWrapper {
       const consumer = this.reusableStream.createConsumer();
 
       for await (const event of consumer) {
-        if (!("type" in event)) continue;
+        if (!("type" in event)) {
+          continue;
+        }
 
         // Transform responses events to chat-like format
         // This is a simplified transformation - you may need to adjust based on your needs