feat(examples): Add func call support (#168)

Some works about simple-chat.
1. fix some bugs.
2. add func call optional.

Signed-off-by: jokemanfire <hu.dingyang@zte.com.cn>

examples/simple-chat-client/README.md

@@ -9,7 +9,7 @@ After configuring the config file, you can run the example:
 ```bash
 ./simple_chat --help                                                       # show help info
 ./simple_chat config > config.toml                                         # output default config to file
-./simple_chat chat --config my_config.toml                                 # start chat with specified config
+./simple_chat --config my_config.toml chat                                 # start chat with specified config
-./simple_chat chat --config my_config.toml --model gpt-4o-mini             # start chat with specified model
+./simple_chat --config my_config.toml --model gpt-4o-mini chat             # start chat with specified model
 ``` 
 

examples/simple-chat-client/src/bin/simple_chat.rs

@@ -95,33 +95,42 @@ async fn main() -> Result<()> {
                     .unwrap_or_else(|| "gpt-4o-mini".to_string()),
             );
 
-            // build system prompt
+            let support_tool = config.support_tool.unwrap_or(true);
-            let mut system_prompt =
+            let mut system_prompt;
-                "you are a assistant, you can help user to complete various tasks. you have the following tools to use:\n".to_string();
+            // if not support tool call, add tool call format guidance
+            if !support_tool {
+                // build system prompt
+                system_prompt =
+            "you are a assistant, you can help user to complete various tasks. you have the following tools to use:\n".to_string();
 
-            // add tool info to system prompt
+                // add tool info to system prompt
-            for tool in session.get_tools() {
+                for tool in session.get_tools() {
-                system_prompt.push_str(&format!(
+                    system_prompt.push_str(&format!(
-                    "\ntool name: {}\ndescription: {}\nparameters: {}\n",
+                        "\ntool name: {}\ndescription: {}\nparameters: {}\n",
-                    tool.name(),
+                        tool.name(),
-                    tool.description(),
+                        tool.description(),
-                    serde_json::to_string_pretty(&tool.parameters())
+                        serde_json::to_string_pretty(&tool.parameters())
-                        .expect("failed to serialize tool parameters")
+                            .expect("failed to serialize tool parameters")
-                ));
+                    ));
+                }
+
+                // add tool call format guidance
+                system_prompt.push_str(
+                    "\nif you need to call tool, please use the following format:\n\
+            Tool: <tool name>\n\
+            Inputs: <inputs>\n",
+                );
+                println!("system prompt: {}", system_prompt);
+            } else {
+                system_prompt =
+                    "you are a assistant, you can help user to complete various tasks.".to_string();
             }
 
-            // add tool call format guidance
-            system_prompt.push_str(
-                "\nif you need to call tool, please use the following format:\n\
-                Tool: <tool name>\n\
-                Inputs: <inputs>\n",
-            );
-
             // add system prompt
             session.add_system_prompt(system_prompt);
 
             // start chat
-            session.chat().await?;
+            session.chat(support_tool).await?;
         }
     }
 

examples/simple-chat-client/src/chat.rs

@@ -4,10 +4,11 @@ use std::{
 };
 
 use anyhow::Result;
+use serde_json;
 
 use crate::{
     client::ChatClient,
-    model::{CompletionRequest, Message},
+    model::{CompletionRequest, Message, ToolFunction},
     tool::{Tool as ToolTrait, ToolSet},
 };
 
@@ -36,7 +37,84 @@ impl ChatSession {
         self.tool_set.tools()
     }
 
-    pub async fn chat(&mut self) -> Result<()> {
+    pub async fn analyze_tool_call(&mut self, response: &Message) {
+        let mut tool_calls_func = Vec::new();
+        if let Some(tool_calls) = response.tool_calls.as_ref() {
+            for tool_call in tool_calls {
+                if tool_call._type == "function" {
+                    tool_calls_func.push(tool_call.function.clone());
+                }
+            }
+        } else {
+            // check if message contains tool call
+            if response.content.contains("Tool:") {
+                let lines: Vec<&str> = response.content.split('\n').collect();
+                // simple parse tool call
+                let mut tool_name = None;
+                let mut args_text = Vec::new();
+                let mut parsing_args = false;
+
+                for line in lines {
+                    if line.starts_with("Tool:") {
+                        tool_name = line.strip_prefix("Tool:").map(|s| s.trim().to_string());
+                        parsing_args = false;
+                    } else if line.starts_with("Inputs:") {
+                        parsing_args = true;
+                    } else if parsing_args {
+                        args_text.push(line.trim());
+                    }
+                }
+                if let Some(name) = tool_name {
+                    tool_calls_func.push(ToolFunction {
+                        name,
+                        arguments: args_text.join("\n"),
+                    });
+                }
+            }
+        }
+        // call tool
+        for tool_call in tool_calls_func {
+            println!("tool call: {:?}", tool_call);
+            let tool = self.tool_set.get_tool(&tool_call.name);
+            if let Some(tool) = tool {
+                // call tool
+                let args = serde_json::from_str::<serde_json::Value>(&tool_call.arguments)
+                    .unwrap_or_default();
+                match tool.call(args).await {
+                    Ok(result) => {
+                        if result.is_error.is_some_and(|b| b) {
+                            self.messages
+                                .push(Message::user("tool call failed, mcp call error"));
+                        } else {
+                            result.content.iter().for_each(|content| {
+                                if let Some(content_text) = content.as_text() {
+                                    let json_result = serde_json::from_str::<serde_json::Value>(
+                                        &content_text.text,
+                                    )
+                                    .unwrap_or_default();
+                                    let pretty_result =
+                                        serde_json::to_string_pretty(&json_result).unwrap();
+                                    println!("call tool result: {}", pretty_result);
+                                    self.messages.push(Message::user(format!(
+                                        "call tool result: {}",
+                                        pretty_result
+                                    )));
+                                }
+                            });
+                        }
+                    }
+                    Err(e) => {
+                        println!("tool call failed: {}", e);
+                        self.messages
+                            .push(Message::user(format!("tool call failed: {}", e)));
+                    }
+                }
+            } else {
+                println!("tool not found: {}", tool_call.name);
+            }
+        }
+    }
+    pub async fn chat(&mut self, support_tool: bool) -> Result<()> {
         println!("welcome to use simple chat client, use 'exit' to quit");
 
         loop {
@@ -56,20 +134,23 @@ impl ChatSession {
             }
 
             self.messages.push(Message::user(&input));
-
+            let tool_definitions = if support_tool {
-            // prepare tool list
+                // prepare tool list
-            let tools = self.tool_set.tools();
+                let tools = self.tool_set.tools();
-            let tool_definitions = if !tools.is_empty() {
+                if !tools.is_empty() {
-                Some(
+                    Some(
-                    tools
+                        tools
-                        .iter()
+                            .iter()
-                        .map(|tool| crate::model::Tool {
+                            .map(|tool| crate::model::Tool {
-                            name: tool.name(),
+                                name: tool.name(),
-                            description: tool.description(),
+                                description: tool.description(),
-                            parameters: tool.parameters(),
+                                parameters: tool.parameters(),
-                        })
+                            })
-                        .collect(),
+                            .collect(),
-                )
+                    )
+                } else {
+                    None
+                }
             } else {
                 None
             };
@@ -84,65 +165,11 @@ impl ChatSession {
 
             // send request
             let response = self.client.complete(request).await?;
-
+            // get choice
-            if let Some(choice) = response.choices.first() {
+            let choice = response.choices.first().unwrap();
-                println!("AI: {}", choice.message.content);
+            println!("AI > {}", choice.message.content);
-                self.messages.push(choice.message.clone());
+            // analyze tool call
-
+            self.analyze_tool_call(&choice.message).await;
-                // check if message contains tool call
-                if choice.message.content.contains("Tool:") {
-                    let lines: Vec<&str> = choice.message.content.split('\n').collect();
-
-                    // simple parse tool call
-                    let mut tool_name = None;
-                    let mut args_text = Vec::new();
-                    let mut parsing_args = false;
-
-                    for line in lines {
-                        if line.starts_with("Tool:") {
-                            tool_name = line.strip_prefix("Tool:").map(|s| s.trim().to_string());
-                            parsing_args = false;
-                        } else if line.starts_with("Inputs:") {
-                            parsing_args = true;
-                        } else if parsing_args {
-                            args_text.push(line.trim());
-                        }
-                    }
-
-                    if let Some(name) = tool_name {
-                        if let Some(tool) = self.tool_set.get_tool(&name) {
-                            println!("calling tool: {}", name);
-
-                            // simple handle args
-                            let args_str = args_text.join("\n");
-                            let args = match serde_json::from_str(&args_str) {
-                                Ok(v) => v,
-                                Err(_) => {
-                                    // try to handle args as string
-                                    serde_json::Value::String(args_str)
-                                }
-                            };
-
-                            // call tool
-                            match tool.call(args).await {
-                                Ok(result) => {
-                                    println!("tool result: {}", result);
-
-                                    // add tool result to dialog
-                                    self.messages.push(Message::user(result));
-                                }
-                                Err(e) => {
-                                    println!("tool call failed: {}", e);
-                                    self.messages
-                                        .push(Message::user(format!("tool call failed: {}", e)));
-                                }
-                            }
-                        } else {
-                            println!("tool not found: {}", name);
-                        }
-                    }
-                }
-            }
         }
 
         Ok(())

examples/simple-chat-client/src/client.rs

@@ -58,8 +58,11 @@ impl ChatClient for OpenAIClient {
             println!("API error: {}", error_text);
             return Err(anyhow::anyhow!("API Error: {}", error_text));
         }
-
+        let text_data = response.text().await?;
-        let completion: CompletionResponse = response.json().await?;
+        println!("Received response: {}", text_data);
+        let completion: CompletionResponse = serde_json::from_str(&text_data)
+            .map_err(anyhow::Error::from)
+            .unwrap();
         Ok(completion)
     }
 }

examples/simple-chat-client/src/config.rs

@@ -11,6 +11,7 @@ pub struct Config {
     pub mcp: Option<McpConfig>,
     pub model_name: Option<String>,
     pub proxy: Option<bool>,
+    pub support_tool: Option<bool>,
 }
 
 #[derive(Debug, Serialize, Deserialize)]

examples/simple-chat-client/src/config.toml

@@ -2,6 +2,7 @@ openai_key = "key"
 chat_url = "url"
 model_name = "model_name"
 proxy = false
+support_tool = true # if support tool call
 
 [mcp]
 [[mcp.server]]

examples/simple-chat-client/src/model.rs

@@ -4,6 +4,8 @@ use serde::{Deserialize, Serialize};
 pub struct Message {
     pub role: String,
     pub content: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub tool_calls: Option<Vec<ToolCall>>,
 }
 
 impl Message {
@@ -11,6 +13,7 @@ impl Message {
         Self {
             role: "system".to_string(),
             content: content.to_string(),
+            tool_calls: None,
         }
     }
 
@@ -18,6 +21,7 @@ impl Message {
         Self {
             role: "user".to_string(),
             content: content.to_string(),
+            tool_calls: None,
         }
     }
 
@@ -25,6 +29,7 @@ impl Message {
         Self {
             role: "assistant".to_string(),
             content: content.to_string(),
+            tool_calls: None,
         }
     }
 }
@@ -62,10 +67,17 @@ pub struct Choice {
     pub finish_reason: String,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Serialize, Deserialize, Clone)]
 pub struct ToolCall {
+    pub id: String,
+    #[serde(rename = "type")]
+    pub _type: String,
+    pub function: ToolFunction,
+}
+#[derive(Debug, Serialize, Deserialize, Clone)]
+pub struct ToolFunction {
     pub name: String,
-    pub arguments: serde_json::Value,
+    pub arguments: String,
 }
 
 #[derive(Debug, Serialize, Deserialize)]

examples/simple-chat-client/src/tool.rs

@@ -3,7 +3,7 @@ use std::{collections::HashMap, sync::Arc};
 use anyhow::Result;
 use async_trait::async_trait;
 use rmcp::{
-    model::{CallToolRequestParam, Tool as McpTool},
+    model::{CallToolRequestParam, CallToolResult, Tool as McpTool},
     service::ServerSink,
 };
 use serde_json::Value;
@@ -18,7 +18,7 @@ pub trait Tool: Send + Sync {
     fn name(&self) -> String;
     fn description(&self) -> String;
     fn parameters(&self) -> Value;
-    async fn call(&self, args: Value) -> Result<String>;
+    async fn call(&self, args: Value) -> Result<CallToolResult>;
 }
 
 pub struct McpToolAdapter {
@@ -50,12 +50,12 @@ impl Tool for McpToolAdapter {
         serde_json::to_value(&self.tool.input_schema).unwrap_or(serde_json::json!({}))
     }
 
-    async fn call(&self, args: Value) -> Result<String> {
+    async fn call(&self, args: Value) -> Result<CallToolResult> {
         let arguments = match args {
             Value::Object(map) => Some(map),
             _ => None,
         };
-
+        println!("arguments: {:?}", arguments);
         let call_result = self
             .server
             .call_tool(CallToolRequestParam {
@@ -63,9 +63,8 @@ impl Tool for McpToolAdapter {
                 arguments,
             })
             .await?;
-        let result = serde_json::to_string(&call_result).unwrap();
 
-        Ok(result)
+        Ok(call_result)
     }
 }
 #[derive(Default)]