Update anthropic function/tool calling

Strip the function call XML from the returned/saved content, which
should allow for model switching between openai/anthropic (and
others?) within the same conversation involving tool calls.

This involves reconstructing the function call XML when sending requests
to anthropic

pkg/lmcli/provider/anthropic/anthropic.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 
 	"git.mlow.ca/mlow/lmcli/pkg/lmcli/model"
+	"git.mlow.ca/mlow/lmcli/pkg/lmcli/provider"
 	"git.mlow.ca/mlow/lmcli/pkg/lmcli/tools"
 )
 
@@ -20,7 +21,7 @@ type AnthropicClient struct {
 
 type Message struct {
 	Role    string `json:"role"`
-	OriginalContent string `json:"content"`
+	Content string `json:"content"`
 }
 
 type Request struct {
@@ -44,7 +45,7 @@ type Response struct {
 	Id      string            `json:"id"`
 	Type    string            `json:"type"`
 	Role    string            `json:"role"`
-	OriginalContent []OriginalContent `json:"content"`
+	Content []OriginalContent `json:"content"`
 }
 
 const FUNCTION_STOP_SEQUENCE = "</function_calls>"
@@ -65,7 +66,7 @@ func buildRequest(params model.RequestParameters, messages []model.Message) Requ
 	}
 
 	startIdx := 0
-	if messages[0].Role == model.MessageRoleSystem {
+	if len(messages) > 0 && messages[0].Role == model.MessageRoleSystem {
 		requestBody.System = messages[0].Content
 		requestBody.Messages = requestBody.Messages[:len(messages)-1]
 		startIdx = 1
@@ -85,8 +86,15 @@ func buildRequest(params model.RequestParameters, messages []model.Message) Requ
 		switch msg.Role {
 		case model.MessageRoleToolCall:
 			message.Role = "assistant"
-			message.OriginalContent = msg.Content
-			//message.ToolCalls = convertToolCallToOpenAI(m.ToolCalls)
+			if msg.Content != "" {
+				message.Content = msg.Content
+			}
+			xmlFuncCalls := convertToolCallsToXMLFunctionCalls(msg.ToolCalls)
+			xmlString, err := xmlFuncCalls.XMLString()
+			if err != nil {
+				panic("Could not serialize []ToolCall to XMLFunctionCall")
+			}
+			message.Content += xmlString
 		case model.MessageRoleToolResult:
 			xmlFuncResults := convertToolResultsToXMLFunctionResult(msg.ToolResults)
 			xmlString, err := xmlFuncResults.XMLString()
@@ -94,10 +102,10 @@ func buildRequest(params model.RequestParameters, messages []model.Message) Requ
 				panic("Could not serialize []ToolResult to XMLFunctionResults")
 			}
 			message.Role = "user"
-			message.OriginalContent = xmlString
+			message.Content = xmlString
 		default:
 			message.Role = string(msg.Role)
-			message.OriginalContent = msg.Content
+			message.Content = msg.Content
 		}
 	}
 	return requestBody
@@ -150,7 +158,7 @@ func (c *AnthropicClient) CreateChatCompletion(
 	}
 
 	sb := strings.Builder{}
-	for _, content := range response.OriginalContent {
+	for _, content := range response.Content {
 		var reply model.Message
 		switch content.Type {
 		case "text":
@@ -279,7 +287,8 @@ func (c *AnthropicClient) CreateChatCompletionStream(
 						// Execute function calls
 						toolCall := model.Message{
 							Role: model.MessageRoleToolCall,
-							Content:   content,
+							// xml stripped from content
+							Content:   content[:start],
 							ToolCalls: convertXMLFunctionCallsToToolCalls(functionCalls),
 						}
 

pkg/lmcli/provider/anthropic/tools.go

@@ -2,6 +2,7 @@ package anthropic
 
 import (
 	"bytes"
+	"fmt"
 	"strings"
 	"text/template"
 
@@ -114,6 +115,25 @@ func convertXMLFunctionCallsToToolCalls(functionCalls XMLFunctionCalls) []model.
 	return toolCalls
 }
 
+func convertToolCallsToXMLFunctionCalls(toolCalls []model.ToolCall) XMLFunctionCalls {
+	converted := make([]XMLFunctionInvoke, len(toolCalls))
+	for i, toolCall := range toolCalls {
+		var params XMLFunctionInvokeParameters
+		var paramXML string
+		for key, value := range toolCall.Parameters {
+			paramXML += fmt.Sprintf("<%s>%v</%s>\n", key, value, key)
+		}
+		params.String = paramXML
+		converted[i] = XMLFunctionInvoke{
+			ToolName:   toolCall.Name,
+			Parameters: params,
+		}
+	}
+	return XMLFunctionCalls{
+		Invoke: converted,
+	}
+}
+
 func convertToolResultsToXMLFunctionResult(toolResults []model.ToolResult) XMLFunctionResults {
 	converted := make([]XMLFunctionResult, len(toolResults))
 	for i, result := range toolResults {
@@ -180,3 +200,22 @@ func (x XMLFunctionResults) XMLString() (string, error) {
 
 	return buf.String(), nil
 }
+
+func (x XMLFunctionCalls) XMLString() (string, error) {
+	tmpl, err := template.New("function_calls").Parse(`<function_calls>
+{{range .Invoke}}<invoke>
+<tool_name>{{.ToolName}}</tool_name>
+<parameters>{{.Parameters.String}}</parameters>
+</invoke>
+{{end}}</function_calls>`)
+	if err != nil {
+		return "", err
+	}
+
+	var buf bytes.Buffer
+	if err := tmpl.Execute(&buf, x); err != nil {
+		return "", err
+	}
+
+	return buf.String(), nil
+}