Add varied messaging experiments

src/ai/openrouter.ts

@@ -256,6 +256,7 @@ ${this.config.openrouter.imageAnalysisPrompt}`;
     attractivenessScore: number | null = null,
     postFlair?: string | null,
     toneGuidance?: string,
+    recentMessages: readonly string[] = [],
   ): Promise<string> {
     try {
       this.logger.debug('Generating message...');
@@ -277,16 +278,7 @@ ${this.config.openrouter.imageAnalysisPrompt}`;
         prompt += `\n\n${toneGuidance}`;
       }
 
-      // Add successful examples if available
-      if (successfulExamples.length > 0) {
-        const examplesText = successfulExamples
-          .map((ex, i) => `Example ${i + 1}:\n${ex}`)
-          .join('\n\n');
-
-        prompt = `Here are some examples of messages that got positive responses:\n\n${examplesText}\n\n---\n\nNow generate a new message in a similar style:\n\n${prompt}`;
-
-        this.logger.debug(`Including ${successfulExamples.length} successful examples in prompt`);
-      }
+      prompt = this.addLearningContext(prompt, successfulExamples, recentMessages);
 
       const message = await this.generateTextWithFallback('generateMessage', prompt, {
         max_tokens: 300,
@@ -414,6 +406,7 @@ Just write the message, nothing else.`;
     strategyPrompt?: string,
     postFlair?: string | null,
     toneGuidance?: string,
+    recentMessages: readonly string[] = [],
   ): Promise<string> {
     try {
       this.logger.debug('Generating chat opener...');
@@ -433,12 +426,7 @@ Just write the message, nothing else.`;
         prompt += `\n\n${toneGuidance}`;
       }
 
-      if (successfulExamples.length > 0) {
-        const examplesText = successfulExamples
-          .map((ex, i) => `Example ${i + 1}:\n${ex}`)
-          .join('\n\n');
-        prompt = `Here are openers that got responses:\n\n${examplesText}\n\n---\n\nNow generate a new opener in a similar style:\n\n${prompt}`;
-      }
+      prompt = this.addLearningContext(prompt, successfulExamples, recentMessages);
 
       const message = await this.generateTextWithFallback('generateChatOpener', prompt, {
         max_tokens: 200,
@@ -476,6 +464,30 @@ Just write the message, nothing else.`;
     };
   }
 
+  private addLearningContext(
+    prompt: string,
+    successfulExamples: readonly string[],
+    recentMessages: readonly string[],
+  ): string {
+    const sections: string[] = [];
+    if (successfulExamples.length > 0) {
+      sections.push(
+        'PERFORMANCE EXAMPLES (use only as evidence about themes that earned replies; do not copy their opening words, sentence structure, or closing hook):\n' +
+        successfulExamples.map((example, index) => `${index + 1}. ${example}`).join('\n'),
+      );
+      this.logger.debug(`Including ${successfulExamples.length} successful message examples as performance context`);
+    }
+    if (recentMessages.length > 0) {
+      sections.push(
+        'RECENT MESSAGES TO AVOID IMITATING:\n' +
+        recentMessages.slice(0, 12).map((message, index) => `${index + 1}. ${message}`).join('\n') +
+        '\nYour output must use different opening words, a different sentence pattern, and a different closing device from these messages.',
+      );
+      this.logger.debug(`Including ${Math.min(recentMessages.length, 12)} recent messages for repetition avoidance`);
+    }
+    return sections.length > 0 ? `${sections.join('\n\n')}\n\n---\n\n${prompt}` : prompt;
+  }
+
   private async generateTextWithFallback(
     label: string,
     prompt: string | ProtectedTextPrompt,
@@ -611,9 +623,20 @@ Just write the message, nothing else.`;
     strategyPrompt?: string,
     postFlair?: string | null,
     toneGuidance?: string,
+    recentMessages: readonly string[] = [],
   ): Promise<{ analysis: ImageAnalysisResult; message: string }> {
     const analysis = await this.analyzeImage(imageBase64, mimeType);
-    const message = await this.generateMessage(analysis.description, postTitle, authorName, successfulExamples, strategyPrompt, analysis.attractivenessScore, postFlair, toneGuidance);
+    const message = await this.generateMessage(
+      analysis.description,
+      postTitle,
+      authorName,
+      successfulExamples,
+      strategyPrompt,
+      analysis.attractivenessScore,
+      postFlair,
+      toneGuidance,
+      recentMessages,
+    );
     return { analysis, message };
   }
 }