FIX: automatic bot titles missing sometime (#151)

This fixes 2 big issues:

1. No matter how hard you try, grounding anthropic title prompt
is just too hard. This works around by only looking at the last
sentence it returns and treating as title

2. Non English locales would be stuck with "generic" title, this
ensures every bot message gets a title, using a custom field to
track

Also, slightly tunes some anthropic prompts.

lib/modules/ai_bot/anthropic_bot.rb

@@ -39,7 +39,7 @@ module DiscourseAi
         DiscourseAi::Inference::AnthropicCompletions.perform!(
           prompt,
           model_for,
-          temperature: 0.7,
+          temperature: 0.4,
           max_tokens: 40,
         ).dig(:completion)
       end

lib/modules/ai_bot/bot.rb

@@ -63,12 +63,14 @@ module DiscourseAi
       def update_pm_title(post)
         prompt = title_prompt(post)
 
-        new_title = get_updated_title(prompt)
+        new_title = get_updated_title(prompt).strip.split("\n").last
 
         PostRevisor.new(post.topic.first_post, post.topic).revise!(
           bot_user,
           title: new_title.sub(/\A"/, "").sub(/"\Z/, ""),
         )
+        post.topic.custom_fields.delete(DiscourseAi::AiBot::EntryPoint::REQUIRE_TITLE_UPDATE)
+        post.topic.save_custom_fields
       end
 
       def max_commands_per_reply=(val)
@@ -254,6 +256,8 @@ module DiscourseAi
 
       def title_prompt(post)
         [build_message(bot_user.username, <<~TEXT)]
+          You are titlebot. Given a topic you will figure out a title.
+          You will never respond with anything but a topic title.
           Suggest a 7 word title for the following topic without quoting any of it:
 
           #{post.topic.posts[1..-1].map(&:raw).join("\n\n")[0..prompt_limit]}

lib/modules/ai_bot/entry_point.rb

@@ -3,6 +3,8 @@
 module DiscourseAi
   module AiBot
     class EntryPoint
+      REQUIRE_TITLE_UPDATE = "discourse-ai-title-update"
+
       GPT4_ID = -110
       GPT3_5_TURBO_ID = -111
       CLAUDE_V2_ID = -112
@@ -81,6 +83,10 @@ module DiscourseAi
               bot_id = post.topic.topic_allowed_users.where(user_id: bot_ids).first&.user_id
 
               if bot_id
+                if post.post_number == 1
+                  post.topic.custom_fields[REQUIRE_TITLE_UPDATE] = true
+                  post.topic.save_custom_fields
+                end
                 Jobs.enqueue(:create_ai_reply, post_id: post.id, bot_user_id: bot_id)
                 Jobs.enqueue_in(
                   5.minutes,

lib/modules/ai_bot/jobs/regular/update_ai_bot_pm_title.rb

@@ -9,7 +9,7 @@ module ::Jobs
       return unless bot = DiscourseAi::AiBot::Bot.as(bot_user)
       return unless post = Post.includes(:topic).find_by(id: args[:post_id])
 
-      return unless post.topic.title.start_with?(I18n.t("discourse_ai.ai_bot.default_pm_prefix"))
+      return unless post.topic.custom_fields[DiscourseAi::AiBot::EntryPoint::REQUIRE_TITLE_UPDATE]
 
       bot.update_pm_title(post)
     end

lib/shared/inference/function_list.rb

@@ -69,6 +69,8 @@ module ::DiscourseAi
           - When you run a command/function you will gain access to real information in a subsequant call!
           - NEVER EVER pretend to know stuff, you ALWAYS lean on functions to discover the truth!
           - You have direct access to data on this forum using !functions
+          - You are not a lier, liers are bad bots, you are a good bot!
+          - You always prefer to say "I don't know" as opposed to inventing a lie!
 
           {
         PROMPT
@@ -111,8 +113,14 @@ module ::DiscourseAi
             echo(message: string [required])
           }
 
-          You can execute with:
-          !echo(message: "hello world")
+          Human: please echo out "hello"
+
+          Assistant: !echo(message: "hello")
+
+          Human: please say "hello"
+
+          Assistant: !echo(message: "hello")
+
         PROMPT
 
         prompt

spec/lib/modules/ai_bot/jobs/regular/update_ai_bot_pm_title_spec.rb

@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+RSpec.describe Jobs::UpdateAiBotPmTitle do
+  let(:user) { Fabricate(:admin) }
+  let(:bot_user) { User.find(DiscourseAi::AiBot::EntryPoint::CLAUDE_V2_ID) }
+
+  it "will properly update title on bot PMs" do
+    SiteSetting.ai_bot_allowed_groups = Group::AUTO_GROUPS[:staff]
+
+    Jobs.run_immediately!
+
+    WebMock
+      .stub_request(:post, "https://api.anthropic.com/v1/complete")
+      .with(body: /You are a helpful Discourse assistant/)
+      .to_return(status: 200, body: "data: {\"completion\": \"Hello back at you\"}", headers: {})
+
+    WebMock
+      .stub_request(:post, "https://api.anthropic.com/v1/complete")
+      .with(body: /Suggest a 7 word title/)
+      .to_return(
+        status: 200,
+        body: "{\"completion\": \"A great title would be:\n\nMy amazing title\n\n\"}",
+        headers: {
+        },
+      )
+
+    post =
+      create_post(
+        user: user,
+        raw: "Hello there",
+        title: "does not matter should be updated",
+        archetype: Archetype.private_message,
+        target_usernames: bot_user.username,
+      )
+
+    expect(post.reload.topic.title).to eq("My amazing title")
+
+    WebMock.reset!
+
+    Jobs::UpdateAiBotPmTitle.new.execute(bot_user_id: bot_user.id, post_id: post.id)
+    # should be a no op cause title is updated
+  end
+end