DEV: Tool support for the LLM service. (#366)

This PR adds tool support to available LLMs. We'll buffer tool invocations and return them instead of making users of this service parse the response.

It also adds support for conversation context in the generic prompt. It includes bot messages, user messages, and tool invocations, which we'll trim to make sure it doesn't exceed the prompt limit, then translate them to the correct dialect.

Finally, It adds some buffering when reading chunks to handle cases when streaming is extremely slow.:M

lib/completions/dialects/chat_gpt.rb

@@ -3,33 +3,101 @@
 module DiscourseAi
   module Completions
     module Dialects
-      class ChatGpt
+      class ChatGpt < Dialect
-        def self.can_translate?(model_name)
+        class << self
+          def can_translate?(model_name)
             %w[gpt-3.5-turbo gpt-4 gpt-3.5-turbo-16k gpt-4-32k].include?(model_name)
           end
 
-        def translate(generic_prompt)
-          open_ai_prompt = [
-            {
-              role: "system",
-              content: [generic_prompt[:insts], generic_prompt[:post_insts].to_s].join("\n"),
-            },
-          ]
-
-          if generic_prompt[:examples]
-            generic_prompt[:examples].each do |example_pair|
-              open_ai_prompt << { role: "user", content: example_pair.first }
-              open_ai_prompt << { role: "assistant", content: example_pair.second }
-            end
-          end
-
-          open_ai_prompt << { role: "user", content: generic_prompt[:input] }
-        end
-
           def tokenizer
             DiscourseAi::Tokenizer::OpenAiTokenizer
           end
         end
+
+        def translate
+          open_ai_prompt = [
+            { role: "system", content: [prompt[:insts], prompt[:post_insts].to_s].join("\n") },
+          ]
+
+          if prompt[:examples]
+            prompt[:examples].each do |example_pair|
+              open_ai_prompt << { role: "user", content: example_pair.first }
+              open_ai_prompt << { role: "assistant", content: example_pair.second }
+            end
+          end
+
+          open_ai_prompt.concat!(conversation_context) if prompt[:conversation_context]
+
+          open_ai_prompt << { role: "user", content: prompt[:input] } if prompt[:input]
+
+          open_ai_prompt
+        end
+
+        def tools
+          return if prompt[:tools].blank?
+
+          prompt[:tools].map { |t| { type: "function", tool: t } }
+        end
+
+        def conversation_context
+          return [] if prompt[:conversation_context].blank?
+
+          trimmed_context = trim_context(prompt[:conversation_context])
+
+          trimmed_context.reverse.map do |context|
+            translated = context.slice(:content)
+            translated[:role] = context[:type]
+
+            if context[:name]
+              if translated[:role] == "tool"
+                translated[:tool_call_id] = context[:name]
+              else
+                translated[:name] = context[:name]
+              end
+            end
+
+            translated
+          end
+        end
+
+        def max_prompt_tokens
+          # provide a buffer of 120 tokens - our function counting is not
+          # 100% accurate and getting numbers to align exactly is very hard
+          buffer = (opts[:max_tokens_to_sample] || 2500) + 50
+
+          if tools.present?
+            # note this is about 100 tokens over, OpenAI have a more optimal representation
+            @function_size ||= self.class.tokenizer.size(tools.to_json.to_s)
+            buffer += @function_size
+          end
+
+          model_max_tokens - buffer
+        end
+
+        private
+
+        def per_message_overhead
+          # open ai defines about 4 tokens per message of overhead
+          4
+        end
+
+        def calculate_message_token(context)
+          self.class.tokenizer.size(context[:content].to_s + context[:name].to_s)
+        end
+
+        def model_max_tokens
+          case model_name
+          when "gpt-3.5-turbo", "gpt-3.5-turbo-16k"
+            16_384
+          when "gpt-4"
+            8192
+          when "gpt-4-32k"
+            32_768
+          else
+            8192
+          end
+        end
+      end
     end
   end
 end

lib/completions/dialects/claude.rb

@@ -3,26 +3,66 @@
 module DiscourseAi
   module Completions
     module Dialects
-      class Claude
+      class Claude < Dialect
-        def self.can_translate?(model_name)
+        class << self
+          def can_translate?(model_name)
             %w[claude-instant-1 claude-2].include?(model_name)
           end
 
-        def translate(generic_prompt)
-          claude_prompt = +"Human: #{generic_prompt[:insts]}\n"
-
-          claude_prompt << build_examples(generic_prompt[:examples]) if generic_prompt[:examples]
-
-          claude_prompt << "#{generic_prompt[:input]}\n"
-
-          claude_prompt << "#{generic_prompt[:post_insts]}\n" if generic_prompt[:post_insts]
-
-          claude_prompt << "Assistant:\n"
-        end
-
           def tokenizer
             DiscourseAi::Tokenizer::AnthropicTokenizer
           end
+        end
+
+        def translate
+          claude_prompt = +"Human: #{prompt[:insts]}\n"
+
+          claude_prompt << build_tools_prompt if prompt[:tools]
+
+          claude_prompt << build_examples(prompt[:examples]) if prompt[:examples]
+
+          claude_prompt << conversation_context if prompt[:conversation_context]
+
+          claude_prompt << "#{prompt[:input]}\n"
+
+          claude_prompt << "#{prompt[:post_insts]}\n" if prompt[:post_insts]
+
+          claude_prompt << "Assistant:\n"
+        end
+
+        def max_prompt_tokens
+          50_000
+        end
+
+        def conversation_context
+          return "" if prompt[:conversation_context].blank?
+
+          trimmed_context = trim_context(prompt[:conversation_context])
+
+          trimmed_context
+            .reverse
+            .reduce(+"") do |memo, context|
+              memo << (context[:type] == "user" ? "Human:" : "Assistant:")
+
+              if context[:type] == "tool"
+                memo << <<~TEXT
+
+                <function_results>
+                <result>
+                <tool_name>#{context[:name]}</tool_name>
+                <json>
+                #{context[:content]}
+                </json>
+                </result>
+                </function_results>
+                TEXT
+              else
+                memo << " " << context[:content] << "\n"
+              end
+
+              memo
+            end
+        end
 
         private
 

lib/completions/dialects/dialect.rb

@@ -0,0 +1,160 @@
+# frozen_string_literal: true
+
+module DiscourseAi
+  module Completions
+    module Dialects
+      class Dialect
+        class << self
+          def can_translate?(_model_name)
+            raise NotImplemented
+          end
+
+          def dialect_for(model_name)
+            dialects = [
+              DiscourseAi::Completions::Dialects::Claude,
+              DiscourseAi::Completions::Dialects::Llama2Classic,
+              DiscourseAi::Completions::Dialects::ChatGpt,
+              DiscourseAi::Completions::Dialects::OrcaStyle,
+              DiscourseAi::Completions::Dialects::Gemini,
+            ]
+            dialects.detect(-> { raise DiscourseAi::Completions::Llm::UNKNOWN_MODEL }) do |d|
+              d.can_translate?(model_name)
+            end
+          end
+
+          def tokenizer
+            raise NotImplemented
+          end
+        end
+
+        def initialize(generic_prompt, model_name, opts: {})
+          @prompt = generic_prompt
+          @model_name = model_name
+          @opts = opts
+        end
+
+        def translate
+          raise NotImplemented
+        end
+
+        def tools
+          tools = +""
+
+          prompt[:tools].each do |function|
+            parameters = +""
+            if function[:parameters].present?
+              function[:parameters].each do |parameter|
+                parameters << <<~PARAMETER
+                  <parameter>
+                  <name>#{parameter[:name]}</name>
+                  <type>#{parameter[:type]}</type>
+                  <description>#{parameter[:description]}</description>
+                  <required>#{parameter[:required]}</required>
+                PARAMETER
+                if parameter[:enum]
+                  parameters << "<options>#{parameter[:enum].join(",")}</options>\n"
+                end
+                parameters << "</parameter>\n"
+              end
+            end
+
+            tools << <<~TOOLS
+              <tool_description>
+              <tool_name>#{function[:name]}</tool_name>
+              <description>#{function[:description]}</description>
+              <parameters>
+              #{parameters}</parameters>
+              </tool_description>
+            TOOLS
+          end
+
+          tools
+        end
+
+        def conversation_context
+          raise NotImplemented
+        end
+
+        def max_prompt_tokens
+          raise NotImplemented
+        end
+
+        private
+
+        attr_reader :prompt, :model_name, :opts
+
+        def trim_context(conversation_context)
+          prompt_limit = max_prompt_tokens
+          current_token_count = calculate_token_count_without_context
+
+          conversation_context.reduce([]) do |memo, context|
+            break(memo) if current_token_count >= prompt_limit
+
+            dupped_context = context.dup
+
+            message_tokens = calculate_message_token(dupped_context)
+
+            # Trimming content to make sure we respect token limit.
+            while dupped_context[:content].present? &&
+                    message_tokens + current_token_count + per_message_overhead > prompt_limit
+              dupped_context[:content] = dupped_context[:content][0..-100] || ""
+              message_tokens = calculate_message_token(dupped_context)
+            end
+
+            next(memo) if dupped_context[:content].blank?
+
+            current_token_count += message_tokens + per_message_overhead
+
+            memo << dupped_context
+          end
+        end
+
+        def calculate_token_count_without_context
+          tokenizer = self.class.tokenizer
+
+          examples_count =
+            prompt[:examples].to_a.sum do |pair|
+              tokenizer.size(pair.join) + (per_message_overhead * 2)
+            end
+          input_count = tokenizer.size(prompt[:input].to_s) + per_message_overhead
+
+          examples_count + input_count +
+            prompt
+              .except(:conversation_context, :tools, :examples, :input)
+              .sum { |_, v| tokenizer.size(v) + per_message_overhead }
+        end
+
+        def per_message_overhead
+          0
+        end
+
+        def calculate_message_token(context)
+          self.class.tokenizer.size(context[:content].to_s)
+        end
+
+        def build_tools_prompt
+          return "" if prompt[:tools].blank?
+
+          <<~TEXT
+            In this environment you have access to a set of tools you can use to answer the user's question.
+            You may call them like this. Only invoke one function at a time and wait for the results before invoking another function:
+            <function_calls>
+            <invoke>
+            <tool_name>$TOOL_NAME</tool_name>
+            <parameters>
+            <$PARAMETER_NAME>$PARAMETER_VALUE</$PARAMETER_NAME>
+            ...
+            </parameters>
+            </invoke>
+            </function_calls>
+
+            Here are the tools available:
+
+            <tools>
+            #{tools}</tools>
+          TEXT
+        end
+      end
+    end
+  end
+end

lib/completions/dialects/gemini.rb

@@ -3,36 +3,93 @@
 module DiscourseAi
   module Completions
     module Dialects
-      class Gemini
+      class Gemini < Dialect
-        def self.can_translate?(model_name)
+        class << self
+          def can_translate?(model_name)
             %w[gemini-pro].include?(model_name)
           end
 
-        def translate(generic_prompt)
-          gemini_prompt = [
-            {
-              role: "user",
-              parts: {
-                text: [generic_prompt[:insts], generic_prompt[:post_insts].to_s].join("\n"),
-              },
-            },
-            { role: "model", parts: { text: "Ok." } },
-          ]
-
-          if generic_prompt[:examples]
-            generic_prompt[:examples].each do |example_pair|
-              gemini_prompt << { role: "user", parts: { text: example_pair.first } }
-              gemini_prompt << { role: "model", parts: { text: example_pair.second } }
-            end
-          end
-
-          gemini_prompt << { role: "user", parts: { text: generic_prompt[:input] } }
-        end
-
           def tokenizer
             DiscourseAi::Tokenizer::OpenAiTokenizer ## TODO Replace with GeminiTokenizer
           end
         end
+
+        def translate
+          gemini_prompt = [
+            {
+              role: "user",
+              parts: {
+                text: [prompt[:insts], prompt[:post_insts].to_s].join("\n"),
+              },
+            },
+            { role: "model", parts: { text: "Ok." } },
+          ]
+
+          if prompt[:examples]
+            prompt[:examples].each do |example_pair|
+              gemini_prompt << { role: "user", parts: { text: example_pair.first } }
+              gemini_prompt << { role: "model", parts: { text: example_pair.second } }
+            end
+          end
+
+          gemini_prompt.concat!(conversation_context) if prompt[:conversation_context]
+
+          gemini_prompt << { role: "user", parts: { text: prompt[:input] } }
+        end
+
+        def tools
+          return if prompt[:tools].blank?
+
+          translated_tools =
+            prompt[:tools].map do |t|
+              required_fields = []
+              tool = t.dup
+
+              tool[:parameters] = t[:parameters].map do |p|
+                required_fields << p[:name] if p[:required]
+
+                p.except(:required)
+              end
+
+              tool.merge(required: required_fields)
+            end
+
+          [{ function_declarations: translated_tools }]
+        end
+
+        def conversation_context
+          return [] if prompt[:conversation_context].blank?
+
+          trimmed_context = trim_context(prompt[:conversation_context])
+
+          trimmed_context.reverse.map do |context|
+            translated = {}
+            translated[:role] = (context[:type] == "user" ? "user" : "model")
+
+            part = {}
+
+            if context[:type] == "tool"
+              part["functionResponse"] = { name: context[:name], content: context[:content] }
+            else
+              part[:text] = context[:content]
+            end
+
+            translated[:parts] = [part]
+
+            translated
+          end
+        end
+
+        def max_prompt_tokens
+          16_384 # 50% of model tokens
+        end
+
+        protected
+
+        def calculate_message_token(context)
+          self.class.tokenizer.size(context[:content].to_s + context[:name].to_s)
+        end
+      end
     end
   end
 end

lib/completions/dialects/llama2_classic.rb

@@ -3,29 +3,74 @@
 module DiscourseAi
   module Completions
     module Dialects
-      class Llama2Classic
+      class Llama2Classic < Dialect
-        def self.can_translate?(model_name)
+        class << self
+          def can_translate?(model_name)
             %w[Llama2-*-chat-hf Llama2-chat-hf].include?(model_name)
           end
 
-        def translate(generic_prompt)
-          llama2_prompt =
-            +"[INST]<<SYS>>#{[generic_prompt[:insts], generic_prompt[:post_insts].to_s].join("\n")}<</SYS>>[/INST]\n"
-
-          if generic_prompt[:examples]
-            generic_prompt[:examples].each do |example_pair|
-              llama2_prompt << "[INST]#{example_pair.first}[/INST]\n"
-              llama2_prompt << "#{example_pair.second}\n"
-            end
-          end
-
-          llama2_prompt << "[INST]#{generic_prompt[:input]}[/INST]\n"
-        end
-
           def tokenizer
             DiscourseAi::Tokenizer::Llama2Tokenizer
           end
         end
+
+        def translate
+          llama2_prompt = +<<~TEXT
+          [INST]
+          <<SYS>>
+          #{prompt[:insts]}
+          #{build_tools_prompt}#{prompt[:post_insts]}
+          <</SYS>>
+          [/INST]
+          TEXT
+
+          if prompt[:examples]
+            prompt[:examples].each do |example_pair|
+              llama2_prompt << "[INST]#{example_pair.first}[/INST]\n"
+              llama2_prompt << "#{example_pair.second}\n"
+            end
+          end
+
+          llama2_prompt << conversation_context if prompt[:conversation_context].present?
+
+          llama2_prompt << "[INST]#{prompt[:input]}[/INST]\n"
+        end
+
+        def conversation_context
+          return "" if prompt[:conversation_context].blank?
+
+          trimmed_context = trim_context(prompt[:conversation_context])
+
+          trimmed_context
+            .reverse
+            .reduce(+"") do |memo, context|
+              if context[:type] == "tool"
+                memo << <<~TEXT
+                [INST]
+                <function_results>
+                <result>
+                <tool_name>#{context[:name]}</tool_name>
+                <json>
+                #{context[:content]}
+                </json>
+                </result>
+                </function_results>
+                [/INST]
+                TEXT
+              elsif context[:type] == "assistant"
+                memo << "[INST]" << context[:content] << "[/INST]\n"
+              else
+                memo << context[:content] << "\n"
+              end
+
+              memo
+            end
+        end
+
+        def max_prompt_tokens
+          SiteSetting.ai_hugging_face_token_limit
+        end
+      end
     end
   end
 end

lib/completions/dialects/orca_style.rb

@@ -3,31 +3,70 @@
 module DiscourseAi
   module Completions
     module Dialects
-      class OrcaStyle
+      class OrcaStyle < Dialect
-        def self.can_translate?(model_name)
+        class << self
+          def can_translate?(model_name)
             %w[StableBeluga2 Upstage-Llama-2-*-instruct-v2].include?(model_name)
           end
 
-        def translate(generic_prompt)
-          orca_style_prompt =
-            +"### System:\n#{[generic_prompt[:insts], generic_prompt[:post_insts].to_s].join("\n")}\n"
-
-          if generic_prompt[:examples]
-            generic_prompt[:examples].each do |example_pair|
-              orca_style_prompt << "### User:\n#{example_pair.first}\n"
-              orca_style_prompt << "### Assistant:\n#{example_pair.second}\n"
-            end
-          end
-
-          orca_style_prompt << "### User:\n#{generic_prompt[:input]}\n"
-
-          orca_style_prompt << "### Assistant:\n"
-        end
-
           def tokenizer
             DiscourseAi::Tokenizer::Llama2Tokenizer
           end
         end
+
+        def translate
+          orca_style_prompt = +<<~TEXT
+          ### System:
+          #{prompt[:insts]}
+          #{build_tools_prompt}#{prompt[:post_insts]}
+          TEXT
+
+          if prompt[:examples]
+            prompt[:examples].each do |example_pair|
+              orca_style_prompt << "### User:\n#{example_pair.first}\n"
+              orca_style_prompt << "### Assistant:\n#{example_pair.second}\n"
+            end
+          end
+
+          orca_style_prompt << "### User:\n#{prompt[:input]}\n"
+
+          orca_style_prompt << "### Assistant:\n"
+        end
+
+        def conversation_context
+          return "" if prompt[:conversation_context].blank?
+
+          trimmed_context = trim_context(prompt[:conversation_context])
+
+          trimmed_context
+            .reverse
+            .reduce(+"") do |memo, context|
+              memo << (context[:type] == "user" ? "### User:" : "### Assistant:")
+
+              if context[:type] == "tool"
+                memo << <<~TEXT
+
+                <function_results>
+                <result>
+                <tool_name>#{context[:name]}</tool_name>
+                <json>
+                #{context[:content]}
+                </json>
+                </result>
+                </function_results>
+                TEXT
+              else
+                memo << " " << context[:content] << "\n"
+              end
+
+              memo
+            end
+        end
+
+        def max_prompt_tokens
+          SiteSetting.ai_hugging_face_token_limit
+        end
+      end
     end
   end
 end

lib/completions/endpoints/anthropic.rb

@@ -22,7 +22,7 @@ module DiscourseAi
           @uri ||= URI("https://api.anthropic.com/v1/complete")
         end
 
-        def prepare_payload(prompt, model_params)
+        def prepare_payload(prompt, model_params, _dialect)
           default_options
             .merge(model_params)
             .merge(prompt: prompt)

lib/completions/endpoints/aws_bedrock.rb

@@ -37,7 +37,7 @@ module DiscourseAi
           URI(api_url)
         end
 
-        def prepare_payload(prompt, model_params)
+        def prepare_payload(prompt, model_params, _dialect)
           default_options.merge(prompt: prompt).merge(model_params)
         end
 

lib/completions/endpoints/base.rb

@@ -30,9 +30,11 @@ module DiscourseAi
           @tokenizer = tokenizer
         end
 
-        def perform_completion!(prompt, user, model_params = {})
+        def perform_completion!(dialect, user, model_params = {})
           @streaming_mode = block_given?
 
+          prompt = dialect.translate
+
           Net::HTTP.start(
             model_uri.host,
             model_uri.port,
@@ -43,7 +45,10 @@ module DiscourseAi
           ) do |http|
             response_data = +""
             response_raw = +""
-            request_body = prepare_payload(prompt, model_params).to_json
+
+            # Needed to response token calculations. Cannot rely on response_data due to function buffering.
+            partials_raw = +""
+            request_body = prepare_payload(prompt, model_params, dialect).to_json
 
             request = prepare_request(request_body)
 
@@ -66,6 +71,15 @@ module DiscourseAi
               if !@streaming_mode
                 response_raw = response.read_body
                 response_data = extract_completion_from(response_raw)
+                partials_raw = response_data.to_s
+
+                if has_tool?("", response_data)
+                  function_buffer = build_buffer # Nokogiri document
+                  function_buffer = add_to_buffer(function_buffer, "", response_data)
+
+                  response_data = +function_buffer.at("function_calls").to_s
+                  response_data << "\n"
+                end
 
                 return response_data
               end
@@ -75,6 +89,7 @@ module DiscourseAi
                 cancel = lambda { cancelled = true }
 
                 leftover = ""
+                function_buffer = build_buffer # Nokogiri document
 
                 response.read_body do |chunk|
                   if cancelled
@@ -85,6 +100,12 @@ module DiscourseAi
                   decoded_chunk = decode(chunk)
                   response_raw << decoded_chunk
 
+                  # Buffering for extremely slow streaming.
+                  if (leftover + decoded_chunk).length < "data: [DONE]".length
+                    leftover += decoded_chunk
+                    next
+                  end
+
                   partials_from(leftover + decoded_chunk).each do |raw_partial|
                     next if cancelled
                     next if raw_partial.blank?
@@ -93,11 +114,27 @@ module DiscourseAi
                       partial = extract_completion_from(raw_partial)
                       next if partial.nil?
                       leftover = ""
+
+                      if has_tool?(response_data, partial)
+                        function_buffer = add_to_buffer(function_buffer, response_data, partial)
+
+                        if buffering_finished?(dialect.tools, function_buffer)
+                          invocation = +function_buffer.at("function_calls").to_s
+                          invocation << "\n"
+
+                          partials_raw << partial.to_s
+                          response_data << invocation
+
+                          yield invocation, cancel
+                        end
+                      else
+                        partials_raw << partial
                         response_data << partial
 
                         yield partial, cancel if partial
+                      end
                     rescue JSON::ParserError
-                      leftover = raw_partial
+                      leftover += decoded_chunk
                     end
                   end
                 end
@@ -109,7 +146,7 @@ module DiscourseAi
             ensure
               if log
                 log.raw_response_payload = response_raw
-                log.response_tokens = tokenizer.size(response_data)
+                log.response_tokens = tokenizer.size(partials_raw)
                 log.save!
 
                 if Rails.env.development?
@@ -165,6 +202,40 @@ module DiscourseAi
         def extract_prompt_for_tokenizer(prompt)
           prompt
         end
+
+        def build_buffer
+          Nokogiri::HTML5.fragment(<<~TEXT)
+          <function_calls>
+          <invoke>
+          <tool_name></tool_name>
+          <tool_id></tool_id>
+          <parameters></parameters>
+          </invoke>
+          </function_calls>
+          TEXT
+        end
+
+        def has_tool?(response, partial)
+          (response + partial).include?("<function_calls>")
+        end
+
+        def add_to_buffer(function_buffer, response_data, partial)
+          new_buffer = Nokogiri::HTML5.fragment(response_data + partial)
+          if tool_name = new_buffer.at("tool_name").text
+            if new_buffer.at("tool_id").nil?
+              tool_id_node =
+                Nokogiri::HTML5::DocumentFragment.parse("\n<tool_id>#{tool_name}</tool_id>")
+
+              new_buffer.at("invoke").children[1].add_next_sibling(tool_id_node)
+            end
+          end
+
+          new_buffer
+        end
+
+        def buffering_finished?(_available_functions, buffer)
+          buffer.to_s.include?("</function_calls>")
+        end
       end
     end
   end

lib/completions/endpoints/canned_response.rb

@@ -31,10 +31,15 @@ module DiscourseAi
             cancelled = false
             cancel_fn = lambda { cancelled = true }
 
+            # We buffer and return tool invocations in one go.
+            if is_tool?(response)
+              yield(response, cancel_fn)
+            else
               response.each_char do |char|
                 break if cancelled
                 yield(char, cancel_fn)
               end
+            end
           else
             response
           end
@@ -43,6 +48,12 @@ module DiscourseAi
         def tokenizer
           DiscourseAi::Tokenizer::OpenAiTokenizer
         end
+
+        private
+
+        def is_tool?(response)
+          Nokogiri::HTML5.fragment(response).at("function_calls").present?
+        end
       end
     end
   end

lib/completions/endpoints/gemini.rb

@@ -25,8 +25,11 @@ module DiscourseAi
           URI(url)
         end
 
-        def prepare_payload(prompt, model_params)
+        def prepare_payload(prompt, model_params, dialect)
-          default_options.merge(model_params).merge(contents: prompt)
+          default_options
+            .merge(model_params)
+            .merge(contents: prompt)
+            .tap { |payload| payload[:tools] = dialect.tools if dialect.tools.present? }
         end
 
         def prepare_request(payload)
@@ -36,25 +39,72 @@ module DiscourseAi
         end
 
         def extract_completion_from(response_raw)
-          if @streaming_mode
-            parsed = response_raw
-          else
           parsed = JSON.parse(response_raw, symbolize_names: true)
-          end
 
-          completion = dig_text(parsed).to_s
+          response_h = parsed.dig(:candidates, 0, :content, :parts, 0)
+
+          has_function_call = response_h.dig(:functionCall).present?
+          has_function_call ? response_h[:functionCall] : response_h.dig(:text)
         end
 
         def partials_from(decoded_chunk)
-          JSON.parse(decoded_chunk, symbolize_names: true)
+          decoded_chunk
+            .split("\n")
+            .map do |line|
+              if line == ","
+                nil
+              elsif line.starts_with?("[")
+                line[1..-1]
+              elsif line.ends_with?("]")
+                line[0..-1]
+              else
+                line
+              end
+            end
+            .compact_blank
         end
 
         def extract_prompt_for_tokenizer(prompt)
           prompt.to_s
         end
 
-        def dig_text(response)
+        def has_tool?(_response_data, partial)
-          response.dig(:candidates, 0, :content, :parts, 0, :text)
+          partial.is_a?(Hash) && partial.has_key?(:name) # Has function name
+        end
+
+        def add_to_buffer(function_buffer, _response_data, partial)
+          if partial[:name].present?
+            function_buffer.at("tool_name").content = partial[:name]
+            function_buffer.at("tool_id").content = partial[:name]
+          end
+
+          if partial[:args]
+            argument_fragments =
+              partial[:args].reduce(+"") do |memo, (arg_name, value)|
+                memo << "\n<#{arg_name}>#{value}</#{arg_name}>"
+              end
+            argument_fragments << "\n"
+
+            function_buffer.at("parameters").children =
+              Nokogiri::HTML5::DocumentFragment.parse(argument_fragments)
+          end
+
+          function_buffer
+        end
+
+        def buffering_finished?(available_functions, buffer)
+          tool_name = buffer.at("tool_name")&.text
+          return false if tool_name.blank?
+
+          signature =
+            available_functions.dig(0, :function_declarations).find { |f| f[:name] == tool_name }
+
+          signature[:parameters].reduce(true) do |memo, param|
+            param_present = buffer.at(param[:name]).present?
+            next(memo) if param_present || !signature[:required].include?(param[:name])
+
+            memo && param_present
+          end
         end
       end
     end

lib/completions/endpoints/hugging_face.rb

@@ -11,7 +11,7 @@ module DiscourseAi
         end
 
         def default_options
-          { parameters: { repetition_penalty: 1.1, temperature: 0.7 } }
+          { parameters: { repetition_penalty: 1.1, temperature: 0.7, return_full_text: false } }
         end
 
         def provider_id
@@ -24,7 +24,7 @@ module DiscourseAi
           URI(SiteSetting.ai_hugging_face_api_url)
         end
 
-        def prepare_payload(prompt, model_params)
+        def prepare_payload(prompt, model_params, _dialect)
           default_options
             .merge(inputs: prompt)
             .tap do |payload|
@@ -33,7 +33,6 @@ module DiscourseAi
               token_limit = SiteSetting.ai_hugging_face_token_limit || 4_000
 
               payload[:parameters][:max_new_tokens] = token_limit - prompt_size(prompt)
-              payload[:parameters][:return_full_text] = false
 
               payload[:stream] = true if @streaming_mode
             end

lib/completions/endpoints/open_ai.rb

@@ -37,11 +37,14 @@ module DiscourseAi
           URI(url)
         end
 
-        def prepare_payload(prompt, model_params)
+        def prepare_payload(prompt, model_params, dialect)
           default_options
             .merge(model_params)
             .merge(messages: prompt)
-            .tap { |payload| payload[:stream] = true if @streaming_mode }
+            .tap do |payload|
+              payload[:stream] = true if @streaming_mode
+              payload[:tools] = dialect.tools if dialect.tools.present?
+            end
         end
 
         def prepare_request(payload)
@@ -62,15 +65,12 @@ module DiscourseAi
         end
 
         def extract_completion_from(response_raw)
-          parsed = JSON.parse(response_raw, symbolize_names: true)
+          parsed = JSON.parse(response_raw, symbolize_names: true).dig(:choices, 0)
 
-          (
+          response_h = @streaming_mode ? parsed.dig(:delta) : parsed.dig(:message)
-            if @streaming_mode
+
-              parsed.dig(:choices, 0, :delta, :content)
+          has_function_call = response_h.dig(:tool_calls).present?
-            else
+          has_function_call ? response_h.dig(:tool_calls, 0, :function) : response_h.dig(:content)
-              parsed.dig(:choices, 0, :message, :content)
-            end
-          ).to_s
         end
 
         def partials_from(decoded_chunk)
@@ -86,6 +86,42 @@ module DiscourseAi
         def extract_prompt_for_tokenizer(prompt)
           prompt.map { |message| message[:content] || message["content"] || "" }.join("\n")
         end
+
+        def has_tool?(_response_data, partial)
+          partial.is_a?(Hash) && partial.has_key?(:name) # Has function name
+        end
+
+        def add_to_buffer(function_buffer, _response_data, partial)
+          function_buffer.at("tool_name").content = partial[:name] if partial[:name].present?
+          function_buffer.at("tool_id").content = partial[:id] if partial[:id].present?
+
+          if partial[:arguments]
+            argument_fragments =
+              partial[:arguments].reduce(+"") do |memo, (arg_name, value)|
+                memo << "\n<#{arg_name}>#{value}</#{arg_name}>"
+              end
+            argument_fragments << "\n"
+
+            function_buffer.at("parameters").children =
+              Nokogiri::HTML5::DocumentFragment.parse(argument_fragments)
+          end
+
+          function_buffer
+        end
+
+        def buffering_finished?(available_functions, buffer)
+          tool_name = buffer.at("tool_name")&.text
+          return false if tool_name.blank?
+
+          signature = available_functions.find { |f| f.dig(:tool, :name) == tool_name }[:tool]
+
+          signature[:parameters].reduce(true) do |memo, param|
+            param_present = buffer.at(param[:name]).present?
+            next(memo) if param_present && !param[:required]
+
+            memo && param_present
+          end
+        end
       end
     end
   end

lib/completions/llm.rb

@@ -24,35 +24,26 @@ module DiscourseAi
       end
 
       def self.proxy(model_name)
-        dialects = [
+        dialect_klass = DiscourseAi::Completions::Dialects::Dialect.dialect_for(model_name)
-          DiscourseAi::Completions::Dialects::Claude,
-          DiscourseAi::Completions::Dialects::Llama2Classic,
-          DiscourseAi::Completions::Dialects::ChatGpt,
-          DiscourseAi::Completions::Dialects::OrcaStyle,
-          DiscourseAi::Completions::Dialects::Gemini,
-        ]
 
-        dialect =
+        return new(dialect_klass, @canned_response, model_name) if @canned_response
-          dialects.detect(-> { raise UNKNOWN_MODEL }) { |d| d.can_translate?(model_name) }.new
-
-        return new(dialect, @canned_response, model_name) if @canned_response
 
         gateway =
           DiscourseAi::Completions::Endpoints::Base.endpoint_for(model_name).new(
             model_name,
-            dialect.tokenizer,
+            dialect_klass.tokenizer,
           )
 
-        new(dialect, gateway, model_name)
+        new(dialect_klass, gateway, model_name)
       end
 
-      def initialize(dialect, gateway, model_name)
+      def initialize(dialect_klass, gateway, model_name)
-        @dialect = dialect
+        @dialect_klass = dialect_klass
         @gateway = gateway
         @model_name = model_name
       end
 
-      delegate :tokenizer, to: :dialect
+      delegate :tokenizer, to: :dialect_klass
 
       # @param generic_prompt { Hash } - Prompt using our generic format.
       # We use the following keys from the hash:
@@ -60,23 +51,64 @@ module DiscourseAi
       #   - input: String containing user input
       #   - examples (optional): Array of arrays with examples of input and responses. Each array is a input/response pair like [[example1, response1], [example2, response2]].
       #   - post_insts (optional): Additional instructions for the LLM. Some dialects like Claude add these at the end of the prompt.
+      #   - conversation_context (optional): Array of hashes to provide context about an ongoing conversation with the model.
+      #     We translate the array in reverse order, meaning the first element would be the most recent message in the conversation.
+      #     Example:
+      #
+      #   [
+      #    { type: "user", name: "user1", content: "This is a new message by a user" },
+      #    { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+      #    { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      #   ]
+      #
+      #   - tools (optional - only functions supported): Array of functions a model can call. Each function is defined as a hash. Example:
+      #
+      #     {
+      #       name: "get_weather",
+      #       description: "Get the weather in a city",
+      #       parameters: [
+      #         { name: "location", type: "string", description: "the city name", required: true },
+      #         {
+      #           name: "unit",
+      #           type: "string",
+      #           description: "the unit of measurement celcius c or fahrenheit f",
+      #           enum: %w[c f],
+      #           required: true,
+      #         },
+      #       ],
+      #     }
       #
       # @param user { User } - User requesting the summary.
       #
       # @param &on_partial_blk { Block - Optional } - The passed block will get called with the LLM partial response alongside a cancel function.
       #
       # @returns { String } - Completion result.
+      #
+      # When the model invokes a tool, we'll wait until the endpoint finishes replying and feed you a fully-formed tool,
+      # even if you passed a partial_read_blk block. Invocations are strings that look like this:
+      #
+      # <function_calls>
+      #   <invoke>
+      #   <tool_name>get_weather</tool_name>
+      #   <tool_id>get_weather</tool_id>
+      #   <parameters>
+      #     <location>Sydney</location>
+      #     <unit>c</unit>
+      #   </parameters>
+      #  </invoke>
+      # </function_calls>
+      #
       def completion!(generic_prompt, user, &partial_read_blk)
-        prompt = dialect.translate(generic_prompt)
-
         model_params = generic_prompt.dig(:params, model_name) || {}
 
-        gateway.perform_completion!(prompt, user, model_params, &partial_read_blk)
+        dialect = dialect_klass.new(generic_prompt, model_name, opts: model_params)
+
+        gateway.perform_completion!(dialect, user, model_params, &partial_read_blk)
       end
 
       private
 
-      attr_reader :dialect, :gateway, :model_name
+      attr_reader :dialect_klass, :gateway, :model_name
     end
   end
 end

spec/lib/completions/dialects/chat_gpt_spec.rb

@@ -1,7 +1,24 @@
 # frozen_string_literal: true
 
 RSpec.describe DiscourseAi::Completions::Dialects::ChatGpt do
-  subject(:dialect) { described_class.new }
+  subject(:dialect) { described_class.new(prompt, "gpt-4") }
+
+  let(:tool) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name", required: true },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+          required: true,
+        },
+      ],
+    }
+  end
 
   let(:prompt) do
     {
@@ -25,6 +42,7 @@ RSpec.describe DiscourseAi::Completions::Dialects::ChatGpt do
     TEXT
       post_insts:
         "Please put the translation between <ai></ai> tags and separate each title with a comma.",
+      tools: [tool],
     }
   end
 
@@ -35,7 +53,7 @@ RSpec.describe DiscourseAi::Completions::Dialects::ChatGpt do
         { role: "user", content: prompt[:input] },
       ]
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to contain_exactly(*open_ai_version)
     end
@@ -55,9 +73,51 @@ RSpec.describe DiscourseAi::Completions::Dialects::ChatGpt do
         { role: "user", content: prompt[:input] },
       ]
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to contain_exactly(*open_ai_version)
     end
   end
+
+  describe "#conversation_context" do
+    let(:context) do
+      [
+        { type: "user", name: "user1", content: "This is a new message by a user" },
+        { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+        { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      ]
+    end
+
+    it "adds conversation in reverse order (first == newer)" do
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context).to eq(
+        [
+          { role: "tool", content: context.last[:content], tool_call_id: context.last[:name] },
+          { role: "assistant", content: context.second[:content] },
+          { role: "user", content: context.first[:content], name: context.first[:name] },
+        ],
+      )
+    end
+
+    it "trims content if it's getting too long" do
+      context.last[:content] = context.last[:content] * 1000
+
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context.last[:content].length).to be < context.last[:content].length
+    end
+  end
+
+  describe "#tools" do
+    it "returns a list of available tools" do
+      open_ai_tool_f = { type: "function", tool: tool }
+
+      expect(subject.tools).to contain_exactly(open_ai_tool_f)
+    end
+  end
 end

spec/lib/completions/dialects/claude_spec.rb

@@ -1,7 +1,24 @@
 # frozen_string_literal: true
 
 RSpec.describe DiscourseAi::Completions::Dialects::Claude do
-  subject(:dialect) { described_class.new }
+  subject(:dialect) { described_class.new(prompt, "claude-2") }
+
+  let(:tool) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name", required: true },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+          required: true,
+        },
+      ],
+    }
+  end
 
   let(:prompt) do
     {
@@ -37,7 +54,7 @@ RSpec.describe DiscourseAi::Completions::Dialects::Claude do
       Assistant:
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to eq(anthropic_version)
     end
@@ -60,9 +77,111 @@ RSpec.describe DiscourseAi::Completions::Dialects::Claude do
       Assistant:
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
+
+      expect(translated).to eq(anthropic_version)
+    end
+
+    it "include tools inside the prompt" do
+      prompt[:tools] = [tool]
+
+      anthropic_version = <<~TEXT
+      Human: #{prompt[:insts]}
+      In this environment you have access to a set of tools you can use to answer the user's question.
+      You may call them like this. Only invoke one function at a time and wait for the results before invoking another function:
+      <function_calls>
+      <invoke>
+      <tool_name>$TOOL_NAME</tool_name>
+      <parameters>
+      <$PARAMETER_NAME>$PARAMETER_VALUE</$PARAMETER_NAME>
+      ...
+      </parameters>
+      </invoke>
+      </function_calls>
+
+      Here are the tools available:
+      
+      <tools>
+      #{dialect.tools}</tools>
+      #{prompt[:input]}
+      #{prompt[:post_insts]}
+      Assistant:
+      TEXT
+
+      translated = dialect.translate
 
       expect(translated).to eq(anthropic_version)
     end
   end
+
+  describe "#conversation_context" do
+    let(:context) do
+      [
+        { type: "user", name: "user1", content: "This is a new message by a user" },
+        { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+        { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      ]
+    end
+
+    it "adds conversation in reverse order (first == newer)" do
+      prompt[:conversation_context] = context
+
+      expected = <<~TEXT
+      Assistant:
+      <function_results>
+      <result>
+      <tool_name>tool_id</tool_name>
+      <json>
+      #{context.last[:content]}
+      </json>
+      </result>
+      </function_results>
+      Assistant: #{context.second[:content]}
+      Human: #{context.first[:content]}
+      TEXT
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context).to eq(expected)
+    end
+
+    it "trims content if it's getting too long" do
+      context.last[:content] = context.last[:content] * 10_000
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context.length).to be < context.last[:content].length
+    end
+  end
+
+  describe "#tools" do
+    it "translates tools to the tool syntax" do
+      prompt[:tools] = [tool]
+
+      translated_tool = <<~TEXT
+        <tool_description>
+        <tool_name>get_weather</tool_name>
+        <description>Get the weather in a city</description>
+        <parameters>
+        <parameter>
+        <name>location</name>
+        <type>string</type>
+        <description>the city name</description>
+        <required>true</required>
+        </parameter>
+        <parameter>
+        <name>unit</name>
+        <type>string</type>
+        <description>the unit of measurement celcius c or fahrenheit f</description>
+        <required>true</required>
+        <options>c,f</options>
+        </parameter>
+        </parameters>
+        </tool_description>
+      TEXT
+
+      expect(dialect.tools).to eq(translated_tool)
+    end
+  end
 end

spec/lib/completions/dialects/gemini_spec.rb

@@ -1,7 +1,24 @@
 # frozen_string_literal: true
 
 RSpec.describe DiscourseAi::Completions::Dialects::Gemini do
-  subject(:dialect) { described_class.new }
+  subject(:dialect) { described_class.new(prompt, "gemini-pro") }
+
+  let(:tool) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name", required: true },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+          required: true,
+        },
+      ],
+    }
+  end
 
   let(:prompt) do
     {
@@ -25,6 +42,7 @@ RSpec.describe DiscourseAi::Completions::Dialects::Gemini do
     TEXT
       post_insts:
         "Please put the translation between <ai></ai> tags and separate each title with a comma.",
+      tools: [tool],
     }
   end
 
@@ -36,7 +54,7 @@ RSpec.describe DiscourseAi::Completions::Dialects::Gemini do
         { role: "user", parts: { text: prompt[:input] } },
       ]
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to eq(gemini_version)
     end
@@ -57,9 +75,79 @@ RSpec.describe DiscourseAi::Completions::Dialects::Gemini do
         { role: "user", parts: { text: prompt[:input] } },
       ]
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to contain_exactly(*gemini_version)
     end
   end
+
+  describe "#conversation_context" do
+    let(:context) do
+      [
+        { type: "user", name: "user1", content: "This is a new message by a user" },
+        { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+        { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      ]
+    end
+
+    it "adds conversation in reverse order (first == newer)" do
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context).to eq(
+        [
+          {
+            role: "model",
+            parts: [
+              {
+                "functionResponse" => {
+                  name: context.last[:name],
+                  content: context.last[:content],
+                },
+              },
+            ],
+          },
+          { role: "model", parts: [{ text: context.second[:content] }] },
+          { role: "user", parts: [{ text: context.first[:content] }] },
+        ],
+      )
+    end
+
+    it "trims content if it's getting too long" do
+      context.last[:content] = context.last[:content] * 1000
+
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context.last.dig(:parts, 0, :text).length).to be <
+        context.last[:content].length
+    end
+  end
+
+  describe "#tools" do
+    it "returns a list of available tools" do
+      gemini_tools = {
+        function_declarations: [
+          {
+            name: "get_weather",
+            description: "Get the weather in a city",
+            parameters: [
+              { name: "location", type: "string", description: "the city name" },
+              {
+                name: "unit",
+                type: "string",
+                description: "the unit of measurement celcius c or fahrenheit f",
+                enum: %w[c f],
+              },
+            ],
+            required: %w[location unit],
+          },
+        ],
+      }
+
+      expect(subject.tools).to contain_exactly(gemini_tools)
+    end
+  end
 end

spec/lib/completions/dialects/llama2_classic_spec.rb

@@ -1,7 +1,24 @@
 # frozen_string_literal: true
 
 RSpec.describe DiscourseAi::Completions::Dialects::Llama2Classic do
-  subject(:dialect) { described_class.new }
+  subject(:dialect) { described_class.new(prompt, "Llama2-chat-hf") }
+
+  let(:tool) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name", required: true },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+          required: true,
+        },
+      ],
+    }
+  end
 
   let(:prompt) do
     {
@@ -31,11 +48,16 @@ RSpec.describe DiscourseAi::Completions::Dialects::Llama2Classic do
   describe "#translate" do
     it "translates a prompt written in our generic format to the Llama2 format" do
       llama2_classic_version = <<~TEXT
-      [INST]<<SYS>>#{[prompt[:insts], prompt[:post_insts]].join("\n")}<</SYS>>[/INST]
+      [INST]
+      <<SYS>>
+      #{prompt[:insts]}
+      #{prompt[:post_insts]}
+      <</SYS>>
+      [/INST]
       [INST]#{prompt[:input]}[/INST]
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to eq(llama2_classic_version)
     end
@@ -49,15 +71,126 @@ RSpec.describe DiscourseAi::Completions::Dialects::Llama2Classic do
       ]
 
       llama2_classic_version = <<~TEXT
-      [INST]<<SYS>>#{[prompt[:insts], prompt[:post_insts]].join("\n")}<</SYS>>[/INST]
+      [INST]
+      <<SYS>>
+      #{prompt[:insts]}
+      #{prompt[:post_insts]}
+      <</SYS>>
+      [/INST]
       [INST]#{prompt[:examples][0][0]}[/INST]
       #{prompt[:examples][0][1]}
       [INST]#{prompt[:input]}[/INST]
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
+
+      expect(translated).to eq(llama2_classic_version)
+    end
+
+    it "include tools inside the prompt" do
+      prompt[:tools] = [tool]
+
+      llama2_classic_version = <<~TEXT
+      [INST]
+      <<SYS>>
+      #{prompt[:insts]}
+      In this environment you have access to a set of tools you can use to answer the user's question.
+      You may call them like this. Only invoke one function at a time and wait for the results before invoking another function:
+      <function_calls>
+      <invoke>
+      <tool_name>$TOOL_NAME</tool_name>
+      <parameters>
+      <$PARAMETER_NAME>$PARAMETER_VALUE</$PARAMETER_NAME>
+      ...
+      </parameters>
+      </invoke>
+      </function_calls>
+
+      Here are the tools available:
+      
+      <tools>
+      #{dialect.tools}</tools>
+      #{prompt[:post_insts]}
+      <</SYS>>
+      [/INST]
+      [INST]#{prompt[:input]}[/INST]
+      TEXT
+
+      translated = dialect.translate
 
       expect(translated).to eq(llama2_classic_version)
     end
   end
+
+  describe "#conversation_context" do
+    let(:context) do
+      [
+        { type: "user", name: "user1", content: "This is a new message by a user" },
+        { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+        { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      ]
+    end
+
+    it "adds conversation in reverse order (first == newer)" do
+      prompt[:conversation_context] = context
+
+      expected = <<~TEXT
+      [INST]
+      <function_results>
+      <result>
+      <tool_name>tool_id</tool_name>
+      <json>
+      #{context.last[:content]}
+      </json>
+      </result>
+      </function_results>
+      [/INST]
+      [INST]#{context.second[:content]}[/INST]
+      #{context.first[:content]}
+      TEXT
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context).to eq(expected)
+    end
+
+    it "trims content if it's getting too long" do
+      context.last[:content] = context.last[:content] * 1_000
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context.length).to be < context.last[:content].length
+    end
+  end
+
+  describe "#tools" do
+    it "translates functions to the tool syntax" do
+      prompt[:tools] = [tool]
+
+      translated_tool = <<~TEXT
+        <tool_description>
+        <tool_name>get_weather</tool_name>
+        <description>Get the weather in a city</description>
+        <parameters>
+        <parameter>
+        <name>location</name>
+        <type>string</type>
+        <description>the city name</description>
+        <required>true</required>
+        </parameter>
+        <parameter>
+        <name>unit</name>
+        <type>string</type>
+        <description>the unit of measurement celcius c or fahrenheit f</description>
+        <required>true</required>
+        <options>c,f</options>
+        </parameter>
+        </parameters>
+        </tool_description>
+      TEXT
+
+      expect(dialect.tools).to eq(translated_tool)
+    end
+  end
 end

spec/lib/completions/dialects/orca_style_spec.rb

@@ -1,9 +1,25 @@
 # frozen_string_literal: true
 
 RSpec.describe DiscourseAi::Completions::Dialects::OrcaStyle do
-  subject(:dialect) { described_class.new }
+  subject(:dialect) { described_class.new(prompt, "StableBeluga2") }
+
+  let(:tool) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name", required: true },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+          required: true,
+        },
+      ],
+    }
+  end
 
-  describe "#translate" do
   let(:prompt) do
     {
       insts: <<~TEXT,
@@ -29,16 +45,18 @@ RSpec.describe DiscourseAi::Completions::Dialects::OrcaStyle do
     }
   end
 
+  describe "#translate" do
     it "translates a prompt written in our generic format to the Open AI format" do
       orca_style_version = <<~TEXT
       ### System:
-      #{[prompt[:insts], prompt[:post_insts]].join("\n")}
+      #{prompt[:insts]}
+      #{prompt[:post_insts]}
       ### User:
       #{prompt[:input]}
       ### Assistant:
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
 
       expect(translated).to eq(orca_style_version)
     end
@@ -53,7 +71,8 @@ RSpec.describe DiscourseAi::Completions::Dialects::OrcaStyle do
 
       orca_style_version = <<~TEXT
       ### System:
-      #{[prompt[:insts], prompt[:post_insts]].join("\n")}
+      #{prompt[:insts]}
+      #{prompt[:post_insts]}
       ### User:
       #{prompt[:examples][0][0]}
       ### Assistant:
@@ -63,9 +82,113 @@ RSpec.describe DiscourseAi::Completions::Dialects::OrcaStyle do
       ### Assistant:
       TEXT
 
-      translated = dialect.translate(prompt)
+      translated = dialect.translate
+
+      expect(translated).to eq(orca_style_version)
+    end
+
+    it "include tools inside the prompt" do
+      prompt[:tools] = [tool]
+
+      orca_style_version = <<~TEXT
+      ### System:
+      #{prompt[:insts]}
+      In this environment you have access to a set of tools you can use to answer the user's question.
+      You may call them like this. Only invoke one function at a time and wait for the results before invoking another function:
+      <function_calls>
+      <invoke>
+      <tool_name>$TOOL_NAME</tool_name>
+      <parameters>
+      <$PARAMETER_NAME>$PARAMETER_VALUE</$PARAMETER_NAME>
+      ...
+      </parameters>
+      </invoke>
+      </function_calls>
+
+      Here are the tools available:
+      
+      <tools>
+      #{dialect.tools}</tools>
+      #{prompt[:post_insts]}
+      ### User:
+      #{prompt[:input]}
+      ### Assistant:
+      TEXT
+
+      translated = dialect.translate
 
       expect(translated).to eq(orca_style_version)
     end
   end
+
+  describe "#conversation_context" do
+    let(:context) do
+      [
+        { type: "user", name: "user1", content: "This is a new message by a user" },
+        { type: "assistant", content: "I'm a previous bot reply, that's why there's no user" },
+        { type: "tool", name: "tool_id", content: "I'm a tool result" },
+      ]
+    end
+
+    it "adds conversation in reverse order (first == newer)" do
+      prompt[:conversation_context] = context
+
+      expected = <<~TEXT
+      ### Assistant:
+      <function_results>
+      <result>
+      <tool_name>tool_id</tool_name>
+      <json>
+      #{context.last[:content]}
+      </json>
+      </result>
+      </function_results>
+      ### Assistant: #{context.second[:content]}
+      ### User: #{context.first[:content]}
+      TEXT
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context).to eq(expected)
+    end
+
+    it "trims content if it's getting too long" do
+      context.last[:content] = context.last[:content] * 1_000
+      prompt[:conversation_context] = context
+
+      translated_context = dialect.conversation_context
+
+      expect(translated_context.length).to be < context.last[:content].length
+    end
+  end
+
+  describe "#tools" do
+    it "translates tools to the tool syntax" do
+      prompt[:tools] = [tool]
+
+      translated_tool = <<~TEXT
+        <tool_description>
+        <tool_name>get_weather</tool_name>
+        <description>Get the weather in a city</description>
+        <parameters>
+        <parameter>
+        <name>location</name>
+        <type>string</type>
+        <description>the city name</description>
+        <required>true</required>
+        </parameter>
+        <parameter>
+        <name>unit</name>
+        <type>string</type>
+        <description>the unit of measurement celcius c or fahrenheit f</description>
+        <required>true</required>
+        <options>c,f</options>
+        </parameter>
+        </parameters>
+        </tool_description>
+      TEXT
+
+      expect(dialect.tools).to eq(translated_tool)
+    end
+  end
 end

spec/lib/completions/endpoints/anthropic_spec.rb

@@ -6,7 +6,9 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Anthropic do
   subject(:model) { described_class.new(model_name, DiscourseAi::Tokenizer::AnthropicTokenizer) }
 
   let(:model_name) { "claude-2" }
-  let(:prompt) { "Human: write 3 words\n\n" }
+  let(:generic_prompt) { { insts: "write 3 words" } }
+  let(:dialect) { DiscourseAi::Completions::Dialects::Claude.new(generic_prompt, model_name) }
+  let(:prompt) { dialect.translate }
 
   let(:request_body) { model.default_options.merge(prompt: prompt).to_json }
   let(:stream_request_body) { model.default_options.merge(prompt: prompt, stream: true).to_json }
@@ -23,10 +25,10 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Anthropic do
     }
   end
 
-  def stub_response(prompt, response_text)
+  def stub_response(prompt, response_text, tool_call: false)
     WebMock
       .stub_request(:post, "https://api.anthropic.com/v1/complete")
-      .with(body: model.default_options.merge(prompt: prompt).to_json)
+      .with(body: request_body)
       .to_return(status: 200, body: JSON.dump(response(response_text)))
   end
 
@@ -42,7 +44,7 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Anthropic do
     }.to_json
   end
 
-  def stub_streamed_response(prompt, deltas)
+  def stub_streamed_response(prompt, deltas, tool_call: false)
     chunks =
       deltas.each_with_index.map do |_, index|
         if index == (deltas.length - 1)
@@ -52,13 +54,27 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Anthropic do
         end
       end
 
-    chunks = chunks.join("\n\n")
+    chunks = chunks.join("\n\n").split("")
 
     WebMock
       .stub_request(:post, "https://api.anthropic.com/v1/complete")
-      .with(body: model.default_options.merge(prompt: prompt, stream: true).to_json)
+      .with(body: stream_request_body)
       .to_return(status: 200, body: chunks)
   end
 
+  let(:tool_deltas) { ["<function", <<~REPLY] }
+      _calls>
+      <invoke>
+      <tool_name>get_weather</tool_name>
+      <parameters>
+      <location>Sydney</location>
+      <unit>c</unit>
+      </parameters>
+      </invoke>
+      </function_calls>
+      REPLY
+
+  let(:tool_call) { invocation }
+
   it_behaves_like "an endpoint that can communicate with a completion service"
 end

spec/lib/completions/endpoints/aws_bedrock_spec.rb

@@ -9,10 +9,12 @@ RSpec.describe DiscourseAi::Completions::Endpoints::AwsBedrock do
 
   let(:model_name) { "claude-2" }
   let(:bedrock_name) { "claude-v2" }
-  let(:prompt) { "Human: write 3 words\n\n" }
+  let(:generic_prompt) { { insts: "write 3 words" } }
+  let(:dialect) { DiscourseAi::Completions::Dialects::Claude.new(generic_prompt, model_name) }
+  let(:prompt) { dialect.translate }
 
   let(:request_body) { model.default_options.merge(prompt: prompt).to_json }
-  let(:stream_request_body) { model.default_options.merge(prompt: prompt).to_json }
+  let(:stream_request_body) { request_body }
 
   before do
     SiteSetting.ai_bedrock_access_key_id = "123456"
@@ -20,39 +22,6 @@ RSpec.describe DiscourseAi::Completions::Endpoints::AwsBedrock do
     SiteSetting.ai_bedrock_region = "us-east-1"
   end
 
-  # Copied from https://github.com/bblimke/webmock/issues/629
-  # Workaround for stubbing a streamed response
-  before do
-    mocked_http =
-      Class.new(Net::HTTP) do
-        def request(*)
-          super do |response|
-            response.instance_eval do
-              def read_body(*, &block)
-                if block_given?
-                  @body.each(&block)
-                else
-                  super
-                end
-              end
-            end
-
-            yield response if block_given?
-
-            response
-          end
-        end
-      end
-
-    @original_net_http = Net.send(:remove_const, :HTTP)
-    Net.send(:const_set, :HTTP, mocked_http)
-  end
-
-  after do
-    Net.send(:remove_const, :HTTP)
-    Net.send(:const_set, :HTTP, @original_net_http)
-  end
-
   def response(content)
     {
       completion: content,
@@ -65,7 +34,7 @@ RSpec.describe DiscourseAi::Completions::Endpoints::AwsBedrock do
     }
   end
 
-  def stub_response(prompt, response_text)
+  def stub_response(prompt, response_text, tool_call: false)
     WebMock
       .stub_request(
         :post,
@@ -102,7 +71,7 @@ RSpec.describe DiscourseAi::Completions::Endpoints::AwsBedrock do
     encoder.encode(message)
   end
 
-  def stub_streamed_response(prompt, deltas)
+  def stub_streamed_response(prompt, deltas, tool_call: false)
     chunks =
       deltas.each_with_index.map do |_, index|
         if index == (deltas.length - 1)
@@ -121,5 +90,19 @@ RSpec.describe DiscourseAi::Completions::Endpoints::AwsBedrock do
       .to_return(status: 200, body: chunks)
   end
 
+  let(:tool_deltas) { ["<function", <<~REPLY] }
+  _calls>
+  <invoke>
+  <tool_name>get_weather</tool_name>
+  <parameters>
+  <location>Sydney</location>
+  <unit>c</unit>
+  </parameters>
+  </invoke>
+  </function_calls>
+  REPLY
+
+  let(:tool_call) { invocation }
+
   it_behaves_like "an endpoint that can communicate with a completion service"
 end

spec/lib/completions/endpoints/endpoint_examples.rb

@@ -1,22 +1,86 @@
 # frozen_string_literal: true
 
 RSpec.shared_examples "an endpoint that can communicate with a completion service" do
+  # Copied from https://github.com/bblimke/webmock/issues/629
+  # Workaround for stubbing a streamed response
+  before do
+    mocked_http =
+      Class.new(Net::HTTP) do
+        def request(*)
+          super do |response|
+            response.instance_eval do
+              def read_body(*, &block)
+                if block_given?
+                  @body.each(&block)
+                else
+                  super
+                end
+              end
+            end
+
+            yield response if block_given?
+
+            response
+          end
+        end
+      end
+
+    @original_net_http = Net.send(:remove_const, :HTTP)
+    Net.send(:const_set, :HTTP, mocked_http)
+  end
+
+  after do
+    Net.send(:remove_const, :HTTP)
+    Net.send(:const_set, :HTTP, @original_net_http)
+  end
+
   describe "#perform_completion!" do
     fab!(:user) { Fabricate(:user) }
 
-    let(:response_text) { "1. Serenity\\n2. Laughter\\n3. Adventure" }
+    let(:tool) do
+      {
+        name: "get_weather",
+        description: "Get the weather in a city",
+        parameters: [
+          { name: "location", type: "string", description: "the city name", required: true },
+          {
+            name: "unit",
+            type: "string",
+            description: "the unit of measurement celcius c or fahrenheit f",
+            enum: %w[c f],
+            required: true,
+          },
+        ],
+      }
+    end
+
+    let(:invocation) { <<~TEXT }
+      <function_calls>
+      <invoke>
+      <tool_name>get_weather</tool_name>
+      <tool_id>get_weather</tool_id>
+      <parameters>
+      <location>Sydney</location>
+      <unit>c</unit>
+      </parameters>
+      </invoke>
+      </function_calls>
+    TEXT
 
     context "when using regular mode" do
+      context "with simple prompts" do
+        let(:response_text) { "1. Serenity\\n2. Laughter\\n3. Adventure" }
+
         before { stub_response(prompt, response_text) }
 
         it "can complete a trivial prompt" do
-        completion_response = model.perform_completion!(prompt, user)
+          completion_response = model.perform_completion!(dialect, user)
 
           expect(completion_response).to eq(response_text)
         end
 
         it "creates an audit log for the request" do
-        model.perform_completion!(prompt, user)
+          model.perform_completion!(dialect, user)
 
           expect(AiApiAuditLog.count).to eq(1)
           log = AiApiAuditLog.first
@@ -32,7 +96,27 @@ RSpec.shared_examples "an endpoint that can communicate with a completion servic
         end
       end
 
+      context "with functions" do
+        let(:generic_prompt) do
+          {
+            insts: "You can tell me the weather",
+            input: "Return the weather in Sydney",
+            tools: [tool],
+          }
+        end
+
+        before { stub_response(prompt, tool_call, tool_call: true) }
+
+        it "returns a function invocation" do
+          completion_response = model.perform_completion!(dialect, user)
+
+          expect(completion_response).to eq(invocation)
+        end
+      end
+    end
+
     context "when using stream mode" do
+      context "with simple prompts" do
         let(:deltas) { ["Mount", "ain", " ", "Tree ", "Frog"] }
 
         before { stub_streamed_response(prompt, deltas) }
@@ -40,7 +124,7 @@ RSpec.shared_examples "an endpoint that can communicate with a completion servic
         it "can complete a trivial prompt" do
           completion_response = +""
 
-        model.perform_completion!(prompt, user) do |partial, cancel|
+          model.perform_completion!(dialect, user) do |partial, cancel|
             completion_response << partial
             cancel.call if completion_response.split(" ").length == 2
           end
@@ -51,7 +135,7 @@ RSpec.shared_examples "an endpoint that can communicate with a completion servic
         it "creates an audit log and updates is on each read." do
           completion_response = +""
 
-        model.perform_completion!(prompt, user) do |partial, cancel|
+          model.perform_completion!(dialect, user) do |partial, cancel|
             completion_response << partial
             cancel.call if completion_response.split(" ").length == 2
           end
@@ -67,5 +151,28 @@ RSpec.shared_examples "an endpoint that can communicate with a completion servic
           expect(log.response_tokens).to eq(model.tokenizer.size(deltas[0...-1].join))
         end
       end
+
+      context "with functions" do
+        let(:generic_prompt) do
+          {
+            insts: "You can tell me the weather",
+            input: "Return the weather in Sydney",
+            tools: [tool],
+          }
+        end
+
+        before { stub_streamed_response(prompt, tool_deltas, tool_call: true) }
+
+        it "waits for the invocation to finish before calling the partial" do
+          buffered_partial = ""
+
+          model.perform_completion!(dialect, user) do |partial, cancel|
+            buffered_partial = partial if partial.include?("<function_calls>")
+          end
+
+          expect(buffered_partial).to eq(invocation)
+        end
+      end
+    end
   end
 end

spec/lib/completions/endpoints/gemini_spec.rb

@@ -6,22 +6,60 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Gemini do
   subject(:model) { described_class.new(model_name, DiscourseAi::Tokenizer::OpenAiTokenizer) }
 
   let(:model_name) { "gemini-pro" }
-  let(:prompt) do
+  let(:generic_prompt) { { insts: "You are a helpful bot.", input: "write 3 words" } }
+  let(:dialect) { DiscourseAi::Completions::Dialects::Gemini.new(generic_prompt, model_name) }
+  let(:prompt) { dialect.translate }
+
+  let(:tool_payload) do
+    {
+      name: "get_weather",
+      description: "Get the weather in a city",
+      parameters: [
+        { name: "location", type: "string", description: "the city name" },
+        {
+          name: "unit",
+          type: "string",
+          description: "the unit of measurement celcius c or fahrenheit f",
+          enum: %w[c f],
+        },
+      ],
+      required: %w[location unit],
+    }
+  end
+
+  let(:request_body) do
+    model
+      .default_options
+      .merge(contents: prompt)
+      .tap { |b| b[:tools] = [{ function_declarations: [tool_payload] }] if generic_prompt[:tools] }
+      .to_json
+  end
+  let(:stream_request_body) do
+    model
+      .default_options
+      .merge(contents: prompt)
+      .tap { |b| b[:tools] = [{ function_declarations: [tool_payload] }] if generic_prompt[:tools] }
+      .to_json
+  end
+
+  let(:tool_deltas) do
     [
-      { role: "system", content: "You are a helpful bot." },
+      { "functionCall" => { name: "get_weather", args: {} } },
-      { role: "user", content: "Write 3 words" },
+      { "functionCall" => { name: "get_weather", args: { location: "" } } },
+      { "functionCall" => { name: "get_weather", args: { location: "Sydney", unit: "c" } } },
     ]
   end
 
-  let(:request_body) { model.default_options.merge(contents: prompt).to_json }
+  let(:tool_call) do
-  let(:stream_request_body) { model.default_options.merge(contents: prompt).to_json }
+    { "functionCall" => { name: "get_weather", args: { location: "Sydney", unit: "c" } } }
+  end
 
-  def response(content)
+  def response(content, tool_call: false)
     {
       candidates: [
         {
           content: {
-            parts: [{ text: content }],
+            parts: [(tool_call ? content : { text: content })],
             role: "model",
           },
           finishReason: "STOP",
@@ -45,22 +83,22 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Gemini do
     }
   end
 
-  def stub_response(prompt, response_text)
+  def stub_response(prompt, response_text, tool_call: false)
     WebMock
       .stub_request(
         :post,
         "https://generativelanguage.googleapis.com/v1beta/models/#{model_name}:generateContent?key=#{SiteSetting.ai_gemini_api_key}",
       )
-      .with(body: { contents: prompt })
+      .with(body: request_body)
-      .to_return(status: 200, body: JSON.dump(response(response_text)))
+      .to_return(status: 200, body: JSON.dump(response(response_text, tool_call: tool_call)))
   end
 
-  def stream_line(delta, finish_reason: nil)
+  def stream_line(delta, finish_reason: nil, tool_call: false)
     {
       candidates: [
         {
           content: {
-            parts: [{ text: delta }],
+            parts: [(tool_call ? delta : { text: delta })],
             role: "model",
           },
           finishReason: finish_reason,
@@ -76,24 +114,24 @@ RSpec.describe DiscourseAi::Completions::Endpoints::Gemini do
     }.to_json
   end
 
-  def stub_streamed_response(prompt, deltas)
+  def stub_streamed_response(prompt, deltas, tool_call: false)
     chunks =
       deltas.each_with_index.map do |_, index|
         if index == (deltas.length - 1)
-          stream_line(deltas[index], finish_reason: "STOP")
+          stream_line(deltas[index], finish_reason: "STOP", tool_call: tool_call)
         else
-          stream_line(deltas[index])
+          stream_line(deltas[index], tool_call: tool_call)
         end
       end
 
-    chunks = chunks.join("\n,\n").prepend("[\n").concat("\n]")
+    chunks = chunks.join("\n,\n").prepend("[").concat("\n]").split("")
 
     WebMock
       .stub_request(
         :post,
         "https://generativelanguage.googleapis.com/v1beta/models/#{model_name}:streamGenerateContent?key=#{SiteSetting.ai_gemini_api_key}",
       )
-      .with(body: model.default_options.merge(contents: prompt).to_json)
+      .with(body: stream_request_body)
       .to_return(status: 200, body: chunks)
   end
 

spec/lib/completions/endpoints/hugging_face_spec.rb

@@ -6,10 +6,11 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
   subject(:model) { described_class.new(model_name, DiscourseAi::Tokenizer::Llama2Tokenizer) }
 
   let(:model_name) { "Llama2-*-chat-hf" }
-  let(:prompt) { <<~TEXT }
+  let(:generic_prompt) { { insts: "You are a helpful bot.", input: "write 3 words" } }
-      [INST]<<SYS>>You are a helpful bot.<</SYS>>[/INST]
+  let(:dialect) do
-      [INST]Write 3 words[/INST]
+    DiscourseAi::Completions::Dialects::Llama2Classic.new(generic_prompt, model_name)
-    TEXT
+  end
+  let(:prompt) { dialect.translate }
 
   let(:request_body) do
     model
@@ -18,7 +19,6 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
       .tap do |payload|
         payload[:parameters][:max_new_tokens] = (SiteSetting.ai_hugging_face_token_limit || 4_000) -
           model.prompt_size(prompt)
-        payload[:parameters][:return_full_text] = false
       end
       .to_json
   end
@@ -30,7 +30,6 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
         payload[:parameters][:max_new_tokens] = (SiteSetting.ai_hugging_face_token_limit || 4_000) -
           model.prompt_size(prompt)
         payload[:stream] = true
-        payload[:parameters][:return_full_text] = false
       end
       .to_json
   end
@@ -41,14 +40,14 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
     [{ generated_text: content }]
   end
 
-  def stub_response(prompt, response_text)
+  def stub_response(prompt, response_text, tool_call: false)
     WebMock
       .stub_request(:post, "#{SiteSetting.ai_hugging_face_api_url}")
       .with(body: request_body)
       .to_return(status: 200, body: JSON.dump(response(response_text)))
   end
 
-  def stream_line(delta, finish_reason: nil)
+  def stream_line(delta, deltas, finish_reason: nil)
     +"data: " << {
       token: {
         id: 29_889,
@@ -56,22 +55,22 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
         logprob: -0.08319092,
         special: !!finish_reason,
       },
-      generated_text: finish_reason ? response_text : nil,
+      generated_text: finish_reason ? deltas.join : nil,
       details: nil,
     }.to_json
   end
 
-  def stub_streamed_response(prompt, deltas)
+  def stub_streamed_response(prompt, deltas, tool_call: false)
     chunks =
       deltas.each_with_index.map do |_, index|
         if index == (deltas.length - 1)
-          stream_line(deltas[index], finish_reason: true)
+          stream_line(deltas[index], deltas, finish_reason: true)
         else
-          stream_line(deltas[index])
+          stream_line(deltas[index], deltas)
         end
       end
 
-    chunks = chunks.join("\n\n")
+    chunks = (chunks.join("\n\n") << "data: [DONE]").split("")
 
     WebMock
       .stub_request(:post, "#{SiteSetting.ai_hugging_face_api_url}")
@@ -79,5 +78,29 @@ RSpec.describe DiscourseAi::Completions::Endpoints::HuggingFace do
       .to_return(status: 200, body: chunks)
   end
 
+  let(:tool_deltas) { ["<function", <<~REPLY, <<~REPLY] }
+      _calls>
+      <invoke>
+      <tool_name>get_weather</tool_name>
+      <parameters>
+      <location>Sydney</location>
+      <unit>c</unit>
+      </parameters>
+      </invoke>
+      </function_calls>
+      REPLY
+      <function_calls>
+      <invoke>
+      <tool_name>get_weather</tool_name>
+      <parameters>
+      <location>Sydney</location>
+      <unit>c</unit>
+      </parameters>
+      </invoke>
+      </function_calls>
+      REPLY
+
+  let(:tool_call) { invocation }
+
   it_behaves_like "an endpoint that can communicate with a completion service"
 end

spec/lib/completions/endpoints/open_ai_spec.rb

@@ -6,17 +6,53 @@ RSpec.describe DiscourseAi::Completions::Endpoints::OpenAi do
   subject(:model) { described_class.new(model_name, DiscourseAi::Tokenizer::OpenAiTokenizer) }
 
   let(:model_name) { "gpt-3.5-turbo" }
-  let(:prompt) do
+  let(:generic_prompt) { { insts: "You are a helpful bot.", input: "write 3 words" } }
+  let(:dialect) { DiscourseAi::Completions::Dialects::ChatGpt.new(generic_prompt, model_name) }
+  let(:prompt) { dialect.translate }
+
+  let(:tool_deltas) do
     [
-      { role: "system", content: "You are a helpful bot." },
+      { id: "get_weather", name: "get_weather", arguments: {} },
-      { role: "user", content: "Write 3 words" },
+      { id: "get_weather", name: "get_weather", arguments: { location: "" } },
+      { id: "get_weather", name: "get_weather", arguments: { location: "Sydney", unit: "c" } },
     ]
   end
 
-  let(:request_body) { model.default_options.merge(messages: prompt).to_json }
+  let(:tool_call) do
-  let(:stream_request_body) { model.default_options.merge(messages: prompt, stream: true).to_json }
+    { id: "get_weather", name: "get_weather", arguments: { location: "Sydney", unit: "c" } }
+  end
+
+  let(:request_body) do
+    model
+      .default_options
+      .merge(messages: prompt)
+      .tap do |b|
+        b[:tools] = generic_prompt[:tools].map do |t|
+          { type: "function", tool: t }
+        end if generic_prompt[:tools]
+      end
+      .to_json
+  end
+  let(:stream_request_body) do
+    model
+      .default_options
+      .merge(messages: prompt, stream: true)
+      .tap do |b|
+        b[:tools] = generic_prompt[:tools].map do |t|
+          { type: "function", tool: t }
+        end if generic_prompt[:tools]
+      end
+      .to_json
+  end
+
+  def response(content, tool_call: false)
+    message_content =
+      if tool_call
+        { tool_calls: [{ function: content }] }
+      else
+        { content: content }
+      end
 
-  def response(content)
     {
       id: "chatcmpl-6sZfAb30Rnv9Q7ufzFwvQsMpjZh8S",
       object: "chat.completion",
@@ -28,45 +64,52 @@ RSpec.describe DiscourseAi::Completions::Endpoints::OpenAi do
         total_tokens: 499,
       },
       choices: [
-        { message: { role: "assistant", content: content }, finish_reason: "stop", index: 0 },
+        { message: { role: "assistant" }.merge(message_content), finish_reason: "stop", index: 0 },
       ],
     }
   end
 
-  def stub_response(prompt, response_text)
+  def stub_response(prompt, response_text, tool_call: false)
     WebMock
       .stub_request(:post, "https://api.openai.com/v1/chat/completions")
-      .with(body: { model: model_name, messages: prompt })
+      .with(body: request_body)
-      .to_return(status: 200, body: JSON.dump(response(response_text)))
+      .to_return(status: 200, body: JSON.dump(response(response_text, tool_call: tool_call)))
+  end
+
+  def stream_line(delta, finish_reason: nil, tool_call: false)
+    message_content =
+      if tool_call
+        { tool_calls: [{ function: delta }] }
+      else
+        { content: delta }
       end
 
-  def stream_line(delta, finish_reason: nil)
     +"data: " << {
       id: "chatcmpl-#{SecureRandom.hex}",
       object: "chat.completion.chunk",
       created: 1_681_283_881,
       model: "gpt-3.5-turbo-0301",
-      choices: [{ delta: { content: delta } }],
+      choices: [{ delta: message_content }],
       finish_reason: finish_reason,
       index: 0,
     }.to_json
   end
 
-  def stub_streamed_response(prompt, deltas)
+  def stub_streamed_response(prompt, deltas, tool_call: false)
     chunks =
       deltas.each_with_index.map do |_, index|
         if index == (deltas.length - 1)
-          stream_line(deltas[index], finish_reason: "stop_sequence")
+          stream_line(deltas[index], finish_reason: "stop_sequence", tool_call: tool_call)
         else
-          stream_line(deltas[index])
+          stream_line(deltas[index], tool_call: tool_call)
         end
       end
 
-    chunks = chunks.join("\n\n")
+    chunks = (chunks.join("\n\n") << "data: [DONE]").split("")
 
     WebMock
       .stub_request(:post, "https://api.openai.com/v1/chat/completions")
-      .with(body: model.default_options.merge(messages: prompt, stream: true).to_json)
+      .with(body: stream_request_body)
       .to_return(status: 200, body: chunks)
   end
 

spec/lib/completions/llm_spec.rb

@@ -3,7 +3,7 @@
 RSpec.describe DiscourseAi::Completions::Llm do
   subject(:llm) do
     described_class.new(
-      DiscourseAi::Completions::Dialects::OrcaStyle.new,
+      DiscourseAi::Completions::Dialects::OrcaStyle,
       canned_response,
       "Upstage-Llama-2-*-instruct-v2",
     )

spec/requests/ai_helper/assistant_controller_spec.rb

@@ -103,7 +103,7 @@ RSpec.describe DiscourseAi::AiHelper::AssistantController do
           expect(response.status).to eq(200)
           expect(response.parsed_body["suggestions"].first).to eq(translated_text)
           expect(response.parsed_body["diff"]).to eq(expected_diff)
-          expect(spy.prompt.last[:content]).to eq(expected_input)
+          expect(spy.prompt.translate.last[:content]).to eq(expected_input)
         end
       end
     end