prefer prompted user messages over system prompts

This seems to be better supported across different model providers and
seems to influence the model in a stronger way.

Prompt files have been renamed to avoid having them show up in the
DokuWiki translate interface. Multilingual models are fine with
prompting in english only.

Author: splitbrain

helper.php

@@ -183,14 +183,17 @@ public function askQuestion($question, $history = [])
             );
             $prompt = $this->getPrompt('question', [
                 'context' => $context,
+                'question' => $question,
             ]);
         } else {
-            $prompt = $this->getPrompt('noanswer');
+            $prompt = $this->getPrompt('noanswer', [
+                'question' => $question,
+            ]);
             $history = [];
         }
 
         $messages = $this->prepareMessages(
-            $this->getChatModel(), $prompt, $question, $history, $this->getConf('chatHistory')
+            $this->getChatModel(), $prompt, $history, $this->getConf('chatHistory')
         );
         $answer = $this->getChatModel()->getAnswer($messages);
 
@@ -211,9 +214,11 @@ public function askQuestion($question, $history = [])
      */
     public function rephraseChatQuestion($question, $history)
     {
-        $prompt = $this->getPrompt('rephrase');
+        $prompt = $this->getPrompt('rephrase', [
+            'question' => $question,
+        ]);
         $messages = $this->prepareMessages(
-            $this->getRephraseModel(), $prompt, $question, $history, $this->getConf('rephraseHistory')
+            $this->getRephraseModel(), $prompt, $history, $this->getConf('rephraseHistory')
         );
         return $this->getRephraseModel()->getAnswer($messages);
     }
@@ -222,32 +227,26 @@ public function rephraseChatQuestion($question, $history)
      * Prepare the messages for the AI
      *
      * @param ChatInterface $model The used model
-     * @param string $prompt The fully prepared system prompt
-     * @param string $question The user question
+     * @param string $promptedQuestion The user question embedded in a prompt
      * @param array[] $history The chat history [[user, ai], [user, ai], ...]
      * @param int $historySize The maximum number of messages to use from the history
      * @return array An OpenAI compatible array of messages
      */
     protected function prepareMessages(
-        ChatInterface $model, string $prompt, string $question, array $history, int $historySize
+        ChatInterface $model, string $promptedQuestion, array $history, int $historySize
     ): array
     {
         // calculate the space for context
         $remainingContext = $model->getMaxInputTokenLength();
-        $remainingContext -= $this->countTokens($prompt);
-        $remainingContext -= $this->countTokens($question);
+        $remainingContext -= $this->countTokens($promptedQuestion);
         $safetyMargin = $remainingContext * 0.05; // 5% safety margin
         $remainingContext -= $safetyMargin;
         // FIXME we may want to also have an upper limit for the history and not always use the full context
 
         $messages = $this->historyMessages($history, $remainingContext, $historySize);
-        $messages[] = [
-            'role' => 'system',
-            'content' => $prompt
-        ];
         $messages[] = [
             'role' => 'user',
-            'content' => $question
+            'content' => $promptedQuestion
         ];
         return $messages;
     }
@@ -308,7 +307,7 @@ protected function countTokens($text)
      */
     protected function getPrompt($type, $vars = [])
     {
-        $template = file_get_contents($this->localFN('prompt_' . $type));
+        $template = file_get_contents($this->localFN($type, 'prompt'));
         $vars['language'] = $this->getLanguagePrompt();
 
         $replace = [];

lang/en/prompt_noanswer.txt lang/en/noanswer.promptlang/en/prompt_noanswer.txt renamed to lang/en/noanswer.prompt

@@ -1 +1,4 @@
-Given the user's question, tell them that you can't answer it because you couldn't find any matching wiki pages, which is likely because the user has insufficient permissions to access them or the question was off-topic. {{LANGUAGE}}
+Given the user's question, tell them that you can't answer it because you couldn't find any matching wiki pages, which is likely because the user has insufficient permissions to access them or the question was off-topic.
+{{LANGUAGE}}
+
+User Question: {{QUESTION}}

lang/en/prompt_rephrase.txt

@@ -3,3 +3,7 @@ If you don't know the answer, just say that you don't know, don't try to make up
 {{LANGUAGE}}
 ----------------
 {{CONTEXT}}
+----------------
+
+User Question: {{QUESTION}}
+Your Reply:

lang/en/prompt_question.txt lang/en/question.promptlang/en/prompt_question.txt renamed to lang/en/question.prompt

@@ -0,0 +1,6 @@
+Given the previous conversation and the users follow-up question, rephrase the user's follow-up question to be a standalone question that is understandable without the previous context.
+{{LANGUAGE}}
+Only reply with the rephrased question, do not answer it.
+
+Follow-up question: {{QUESTION}}
+Standalone question: