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zclaw_openfang/crates/zclaw-kernel/src/director.rs
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fix(kernel): enable multi-agent compilation + A2A routing tests
- director.rs: add missing CompletionRequest fields (thinking_enabled,
  reasoning_effort, plan_mode) for multi-agent feature gate
- agents.rs: remove unused AgentState import behind multi-agent feature
- lib.rs: replace ambiguous glob re-export with explicit director types,
  resolving AgentRole conflict between director and generation modules
- a2a.rs: add 5 integration tests covering direct message delivery,
  broadcast routing, group messaging, agent unregistration, and
  expired message rejection (10 total A2A tests, all passing)
- Verified: 537 workspace tests pass with multi-agent feature enabled

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-04-04 09:41:24 +08:00

916 lines
29 KiB
Rust

//! Director - Multi-Agent Orchestration (Experimental)
//!
//! The Director manages multi-agent conversations by:
//! - Determining which agent speaks next
//! - Managing conversation state and turn order
//! - Supporting multiple scheduling strategies
//! - Coordinating agent responses
//!
//! **Status**: This module is fully implemented but gated behind the `multi-agent` feature.
//! The desktop build does not currently enable this feature. When multi-agent support
//! is ready for production, add Tauri commands to create and interact with the Director,
//! and enable the feature in `desktop/src-tauri/Cargo.toml`.
use std::sync::Arc;
use serde::{Deserialize, Serialize};
use tokio::sync::{RwLock, Mutex, mpsc};
use zclaw_types::{AgentId, Result, ZclawError};
use zclaw_protocols::{A2aEnvelope, A2aMessageType, A2aRecipient, A2aRouter, A2aAgentProfile, A2aCapability};
use zclaw_runtime::{LlmDriver, CompletionRequest};
/// Director configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DirectorConfig {
/// Maximum turns before ending conversation
pub max_turns: usize,
/// Scheduling strategy
pub strategy: ScheduleStrategy,
/// Whether to include user in the loop
pub include_user: bool,
/// Timeout for agent response (seconds)
pub response_timeout: u64,
/// Whether to allow parallel agent responses
pub allow_parallel: bool,
}
impl Default for DirectorConfig {
fn default() -> Self {
Self {
max_turns: 50,
strategy: ScheduleStrategy::Priority,
include_user: true,
response_timeout: 30,
allow_parallel: false,
}
}
}
/// Scheduling strategy for determining next speaker
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
#[serde(rename_all = "snake_case")]
pub enum ScheduleStrategy {
/// Round-robin through all agents
RoundRobin,
/// Priority-based selection (higher priority speaks first)
Priority,
/// LLM decides who speaks next
LlmDecision,
/// Random selection
Random,
/// Manual (external controller decides)
Manual,
}
/// Agent role in the conversation
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Hash)]
#[serde(rename_all = "snake_case")]
pub enum AgentRole {
/// Main teacher/instructor
Teacher,
/// Teaching assistant
Assistant,
/// Student participant
Student,
/// Moderator/facilitator
Moderator,
/// Expert consultant
Expert,
/// Observer (receives messages but doesn't speak)
Observer,
}
impl AgentRole {
/// Get default priority for this role
pub fn default_priority(&self) -> u8 {
match self {
AgentRole::Teacher => 10,
AgentRole::Moderator => 9,
AgentRole::Expert => 8,
AgentRole::Assistant => 7,
AgentRole::Student => 5,
AgentRole::Observer => 0,
}
}
}
/// Agent configuration for director
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DirectorAgent {
/// Agent ID
pub id: AgentId,
/// Display name
pub name: String,
/// Agent role
pub role: AgentRole,
/// Priority (higher = speaks first)
pub priority: u8,
/// System prompt / persona
pub persona: String,
/// Whether this agent is active
pub active: bool,
/// Maximum turns this agent can speak consecutively
pub max_consecutive_turns: usize,
}
impl DirectorAgent {
/// Create a new director agent
pub fn new(id: AgentId, name: impl Into<String>, role: AgentRole, persona: impl Into<String>) -> Self {
let priority = role.default_priority();
Self {
id,
name: name.into(),
role,
priority,
persona: persona.into(),
active: true,
max_consecutive_turns: 2,
}
}
}
/// Conversation state
#[derive(Debug, Clone, Default)]
pub struct ConversationState {
/// Current turn number
pub turn: usize,
/// Current speaker ID
pub current_speaker: Option<AgentId>,
/// Turn history (agent_id, message_summary)
pub history: Vec<(AgentId, String)>,
/// Consecutive turns by current agent
pub consecutive_turns: usize,
/// Whether conversation is active
pub active: bool,
/// Conversation topic/goal
pub topic: Option<String>,
}
impl ConversationState {
/// Create new conversation state
pub fn new() -> Self {
Self {
turn: 0,
current_speaker: None,
history: Vec::new(),
consecutive_turns: 0,
active: false,
topic: None,
}
}
/// Record a turn
pub fn record_turn(&mut self, agent_id: AgentId, summary: String) {
if self.current_speaker == Some(agent_id) {
self.consecutive_turns += 1;
} else {
self.consecutive_turns = 1;
self.current_speaker = Some(agent_id);
}
self.history.push((agent_id, summary));
self.turn += 1;
}
/// Get last N turns
pub fn get_recent_history(&self, n: usize) -> &[(AgentId, String)] {
let start = self.history.len().saturating_sub(n);
&self.history[start..]
}
/// Check if agent has spoken too many consecutive turns
pub fn is_over_consecutive_limit(&self, agent_id: &AgentId, max: usize) -> bool {
if self.current_speaker == Some(*agent_id) {
self.consecutive_turns >= max
} else {
false
}
}
}
/// The Director orchestrates multi-agent conversations
pub struct Director {
/// Director configuration
config: DirectorConfig,
/// Registered agents
agents: Arc<RwLock<Vec<DirectorAgent>>>,
/// Conversation state
state: Arc<RwLock<ConversationState>>,
/// A2A router for messaging
router: Arc<A2aRouter>,
/// Agent ID for the director itself
director_id: AgentId,
/// Optional LLM driver for intelligent scheduling
llm_driver: Option<Arc<dyn LlmDriver>>,
/// Inbox for receiving responses (stores pending request IDs and their response channels)
pending_requests: Arc<Mutex<std::collections::HashMap<String, mpsc::Sender<A2aEnvelope>>>>,
/// Receiver for incoming messages
inbox: Arc<Mutex<Option<mpsc::Receiver<A2aEnvelope>>>>,
}
impl Director {
/// Create a new director
pub fn new(config: DirectorConfig) -> Self {
let director_id = AgentId::new();
let router = Arc::new(A2aRouter::new(director_id.clone()));
Self {
config,
agents: Arc::new(RwLock::new(Vec::new())),
state: Arc::new(RwLock::new(ConversationState::new())),
router,
director_id,
llm_driver: None,
pending_requests: Arc::new(Mutex::new(std::collections::HashMap::new())),
inbox: Arc::new(Mutex::new(None)),
}
}
/// Create director with existing router
pub fn with_router(config: DirectorConfig, router: Arc<A2aRouter>) -> Self {
let director_id = AgentId::new();
Self {
config,
agents: Arc::new(RwLock::new(Vec::new())),
state: Arc::new(RwLock::new(ConversationState::new())),
router,
director_id,
llm_driver: None,
pending_requests: Arc::new(Mutex::new(std::collections::HashMap::new())),
inbox: Arc::new(Mutex::new(None)),
}
}
/// Initialize the director's inbox (must be called after creation)
pub async fn initialize(&self) -> Result<()> {
let profile = A2aAgentProfile {
id: self.director_id.clone(),
name: "Director".to_string(),
description: "Multi-agent conversation orchestrator".to_string(),
capabilities: vec![A2aCapability {
name: "orchestration".to_string(),
description: "Multi-agent conversation management".to_string(),
input_schema: None,
output_schema: None,
requires_approval: false,
version: "1.0.0".to_string(),
tags: vec!["orchestration".to_string()],
}],
protocols: vec!["a2a".to_string()],
role: "orchestrator".to_string(),
priority: 10,
metadata: Default::default(),
groups: vec![],
last_seen: 0,
};
let rx = self.router.register_agent(profile).await;
*self.inbox.lock().await = Some(rx);
Ok(())
}
/// Set LLM driver for intelligent scheduling
pub fn with_llm_driver(mut self, driver: Arc<dyn LlmDriver>) -> Self {
self.llm_driver = Some(driver);
self
}
/// Set LLM driver (mutable)
pub fn set_llm_driver(&mut self, driver: Arc<dyn LlmDriver>) {
self.llm_driver = Some(driver);
}
/// Register an agent
pub async fn register_agent(&self, agent: DirectorAgent) {
let mut agents = self.agents.write().await;
agents.push(agent);
// Sort by priority (descending)
agents.sort_by(|a, b| b.priority.cmp(&a.priority));
}
/// Remove an agent
pub async fn remove_agent(&self, agent_id: &AgentId) {
let mut agents = self.agents.write().await;
agents.retain(|a| &a.id != agent_id);
}
/// Get all registered agents
pub async fn get_agents(&self) -> Vec<DirectorAgent> {
self.agents.read().await.clone()
}
/// Get active agents sorted by priority
pub async fn get_active_agents(&self) -> Vec<DirectorAgent> {
self.agents
.read()
.await
.iter()
.filter(|a| a.active)
.cloned()
.collect()
}
/// Start a new conversation
pub async fn start_conversation(&self, topic: Option<String>) {
let mut state = self.state.write().await;
state.turn = 0;
state.current_speaker = None;
state.history.clear();
state.consecutive_turns = 0;
state.active = true;
state.topic = topic;
}
/// End the conversation
pub async fn end_conversation(&self) {
let mut state = self.state.write().await;
state.active = false;
}
/// Get current conversation state
pub async fn get_state(&self) -> ConversationState {
self.state.read().await.clone()
}
/// Select the next speaker based on strategy
pub async fn select_next_speaker(&self) -> Option<DirectorAgent> {
let agents = self.get_active_agents().await;
let state = self.state.read().await;
if agents.is_empty() || state.turn >= self.config.max_turns {
return None;
}
match self.config.strategy {
ScheduleStrategy::RoundRobin => {
// Round-robin through active agents
let idx = state.turn % agents.len();
Some(agents[idx].clone())
}
ScheduleStrategy::Priority => {
// Select highest priority agent that hasn't exceeded consecutive limit
for agent in &agents {
if !state.is_over_consecutive_limit(&agent.id, agent.max_consecutive_turns) {
return Some(agent.clone());
}
}
// If all exceeded, pick the highest priority anyway
agents.first().cloned()
}
ScheduleStrategy::Random => {
// Random selection
use std::time::{SystemTime, UNIX_EPOCH};
let now = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap()
.as_nanos();
let idx = (now as usize) % agents.len();
Some(agents[idx].clone())
}
ScheduleStrategy::LlmDecision => {
// LLM-based decision making
self.select_speaker_with_llm(&agents, &state).await
.or_else(|| agents.first().cloned())
}
ScheduleStrategy::Manual => {
// External controller decides
None
}
}
}
/// Use LLM to select the next speaker
async fn select_speaker_with_llm(
&self,
agents: &[DirectorAgent],
state: &ConversationState,
) -> Option<DirectorAgent> {
let driver = self.llm_driver.as_ref()?;
// Build context for LLM decision
let agent_descriptions: String = agents
.iter()
.enumerate()
.map(|(i, a)| format!("{}. {} ({}) - {}", i + 1, a.name, a.role.as_str(), a.persona))
.collect::<Vec<_>>()
.join("\n");
let recent_history: String = state
.get_recent_history(5)
.iter()
.map(|(id, msg)| {
let agent = agents.iter().find(|a| &a.id == id);
let name = agent.map(|a| a.name.as_str()).unwrap_or("Unknown");
format!("- {}: {}", name, msg)
})
.collect::<Vec<_>>()
.join("\n");
let topic = state.topic.as_deref().unwrap_or("General discussion");
let prompt = format!(
r#"You are a conversation director. Select the best agent to speak next.
Topic: {}
Available Agents:
{}
Recent Conversation:
{}
Current turn: {}
Last speaker: {}
Instructions:
1. Consider the conversation flow and topic
2. Choose the agent who should speak next to advance the conversation
3. Avoid having the same agent speak too many times consecutively
4. Consider which role would be most valuable at this point
Respond with ONLY the number (1-{}) of the agent who should speak next. No explanation."#,
topic,
agent_descriptions,
recent_history,
state.turn,
state.current_speaker
.and_then(|id| agents.iter().find(|a| a.id == id))
.map(|a| &a.name)
.unwrap_or(&"None".to_string()),
agents.len()
);
let request = CompletionRequest {
model: "default".to_string(),
system: Some("You are a conversation director. You respond with only a single number.".to_string()),
messages: vec![zclaw_types::Message::User { content: prompt }],
tools: vec![],
max_tokens: Some(10),
temperature: Some(0.3),
stop: vec![],
stream: false,
thinking_enabled: false,
reasoning_effort: None,
plan_mode: false,
};
match driver.complete(request).await {
Ok(response) => {
// Extract text from response
let text = response.content.iter()
.filter_map(|block| match block {
zclaw_runtime::ContentBlock::Text { text } => Some(text.clone()),
_ => None,
})
.collect::<Vec<_>>()
.join("");
// Parse the number
if let Ok(idx) = text.trim().parse::<usize>() {
if idx >= 1 && idx <= agents.len() {
return Some(agents[idx - 1].clone());
}
}
// Fallback to first agent
agents.first().cloned()
}
Err(e) => {
tracing::warn!("LLM speaker selection failed: {}", e);
agents.first().cloned()
}
}
}
/// Send message to selected agent and wait for response
pub async fn send_to_agent(
&self,
agent: &DirectorAgent,
message: String,
) -> Result<String> {
// Create a response channel for this request
let (_response_tx, mut _response_rx) = mpsc::channel::<A2aEnvelope>(1);
let envelope = A2aEnvelope::new(
self.director_id.clone(),
A2aRecipient::Direct { agent_id: agent.id.clone() },
A2aMessageType::Request,
serde_json::json!({
"message": message,
"persona": agent.persona.clone(),
"role": agent.role.clone(),
}),
);
// Store the request ID with its response channel
let request_id = envelope.id.clone();
{
let mut pending = self.pending_requests.lock().await;
pending.insert(request_id.clone(), _response_tx);
}
// Send the request
self.router.route(envelope).await?;
// Wait for response with timeout
let timeout_duration = std::time::Duration::from_secs(self.config.response_timeout);
let request_id_clone = request_id.clone();
let response = tokio::time::timeout(timeout_duration, async {
// Poll the inbox for responses
let mut inbox_guard = self.inbox.lock().await;
if let Some(ref mut rx) = *inbox_guard {
while let Some(msg) = rx.recv().await {
// Check if this is a response to our request
if msg.message_type == A2aMessageType::Response {
if let Some(ref reply_to) = msg.reply_to {
if reply_to == &request_id_clone {
// Found our response
return Some(msg);
}
}
}
// Not our response, continue waiting
// (In a real implementation, we'd re-queue non-matching messages)
}
}
None
}).await;
// Clean up pending request
{
let mut pending = self.pending_requests.lock().await;
pending.remove(&request_id);
}
match response {
Ok(Some(envelope)) => {
// Extract response text from payload
let response_text = envelope.payload
.get("response")
.and_then(|v: &serde_json::Value| v.as_str())
.unwrap_or(&format!("[{}] Response from {}", agent.role.as_str(), agent.name))
.to_string();
Ok(response_text)
}
Ok(None) => {
Err(ZclawError::Timeout("No response received".into()))
}
Err(_) => {
Err(ZclawError::Timeout(format!(
"Agent {} did not respond within {} seconds",
agent.name, self.config.response_timeout
)))
}
}
}
/// Broadcast message to all agents
pub async fn broadcast(&self, message: String) -> Result<()> {
let envelope = A2aEnvelope::new(
self.director_id,
A2aRecipient::Broadcast,
A2aMessageType::Notification,
serde_json::json!({ "message": message }),
);
self.router.route(envelope).await
}
/// Run one turn of the conversation
pub async fn run_turn(&self, input: Option<String>) -> Result<Option<DirectorAgent>> {
let state = self.state.read().await;
if !state.active {
return Err(ZclawError::InvalidInput("Conversation not active".into()));
}
drop(state);
// Select next speaker
let speaker = self.select_next_speaker().await;
if let Some(ref agent) = speaker {
// Build context from recent history
let state = self.state.read().await;
let context = Self::build_context(&state, &input);
// Send message to agent
let response = self.send_to_agent(agent, context).await?;
// Update state
let mut state = self.state.write().await;
let summary = if response.len() > 100 {
format!("{}...", &response[..100])
} else {
response
};
state.record_turn(agent.id, summary);
}
Ok(speaker)
}
/// Build context string for agent
fn build_context(state: &ConversationState, input: &Option<String>) -> String {
let mut context = String::new();
if let Some(ref topic) = state.topic {
context.push_str(&format!("Topic: {}\n\n", topic));
}
if let Some(ref user_input) = input {
context.push_str(&format!("User: {}\n\n", user_input));
}
// Add recent history
if !state.history.is_empty() {
context.push_str("Recent conversation:\n");
for (agent_id, summary) in state.get_recent_history(5) {
context.push_str(&format!("- {}: {}\n", agent_id, summary));
}
}
context
}
/// Run full conversation until complete
pub async fn run_conversation(
&self,
topic: String,
initial_input: Option<String>,
) -> Result<Vec<(AgentId, String)>> {
self.start_conversation(Some(topic.clone())).await;
let mut input = initial_input;
let mut results = Vec::new();
loop {
let state = self.state.read().await;
// Check termination conditions
if state.turn >= self.config.max_turns {
break;
}
if !state.active {
break;
}
drop(state);
// Run one turn
match self.run_turn(input.take()).await {
Ok(Some(_agent)) => {
let state = self.state.read().await;
if let Some((agent_id, summary)) = state.history.last() {
results.push((*agent_id, summary.clone()));
}
}
Ok(None) => {
// Manual mode or no speaker selected
break;
}
Err(e) => {
tracing::error!("Turn error: {}", e);
break;
}
}
// In a real implementation, we would wait for user input here
// if config.include_user is true
}
self.end_conversation().await;
Ok(results)
}
/// Get the director's agent ID
pub fn director_id(&self) -> &AgentId {
&self.director_id
}
}
impl AgentRole {
/// Get role as string
pub fn as_str(&self) -> &'static str {
match self {
AgentRole::Teacher => "teacher",
AgentRole::Assistant => "assistant",
AgentRole::Student => "student",
AgentRole::Moderator => "moderator",
AgentRole::Expert => "expert",
AgentRole::Observer => "observer",
}
}
/// Parse role from string
pub fn from_str(s: &str) -> Option<Self> {
match s.to_lowercase().as_str() {
"teacher" | "instructor" => Some(AgentRole::Teacher),
"assistant" | "ta" => Some(AgentRole::Assistant),
"student" => Some(AgentRole::Student),
"moderator" | "facilitator" => Some(AgentRole::Moderator),
"expert" | "consultant" => Some(AgentRole::Expert),
"observer" => Some(AgentRole::Observer),
_ => None,
}
}
}
/// Builder for creating director configurations
pub struct DirectorBuilder {
config: DirectorConfig,
agents: Vec<DirectorAgent>,
}
impl DirectorBuilder {
/// Create a new builder
pub fn new() -> Self {
Self {
config: DirectorConfig::default(),
agents: Vec::new(),
}
}
/// Set scheduling strategy
pub fn strategy(mut self, strategy: ScheduleStrategy) -> Self {
self.config.strategy = strategy;
self
}
/// Set max turns
pub fn max_turns(mut self, max_turns: usize) -> Self {
self.config.max_turns = max_turns;
self
}
/// Include user in conversation
pub fn include_user(mut self, include: bool) -> Self {
self.config.include_user = include;
self
}
/// Add a teacher agent
pub fn teacher(mut self, id: AgentId, name: impl Into<String>, persona: impl Into<String>) -> Self {
let mut agent = DirectorAgent::new(id, name, AgentRole::Teacher, persona);
agent.priority = 10;
self.agents.push(agent);
self
}
/// Add an assistant agent
pub fn assistant(mut self, id: AgentId, name: impl Into<String>, persona: impl Into<String>) -> Self {
let mut agent = DirectorAgent::new(id, name, AgentRole::Assistant, persona);
agent.priority = 7;
self.agents.push(agent);
self
}
/// Add a student agent
pub fn student(mut self, id: AgentId, name: impl Into<String>, persona: impl Into<String>) -> Self {
let mut agent = DirectorAgent::new(id, name, AgentRole::Student, persona);
agent.priority = 5;
self.agents.push(agent);
self
}
/// Add a custom agent
pub fn agent(mut self, agent: DirectorAgent) -> Self {
self.agents.push(agent);
self
}
/// Build the director
pub async fn build(self) -> Director {
let director = Director::new(self.config);
for agent in self.agents {
director.register_agent(agent).await;
}
director
}
}
impl Default for DirectorBuilder {
fn default() -> Self {
Self::new()
}
}
#[cfg(test)]
mod tests {
use super::*;
#[tokio::test]
async fn test_director_creation() {
let director = Director::new(DirectorConfig::default());
let agents = director.get_agents().await;
assert!(agents.is_empty());
}
#[tokio::test]
async fn test_register_agents() {
let director = Director::new(DirectorConfig::default());
director.register_agent(DirectorAgent::new(
AgentId::new(),
"Teacher",
AgentRole::Teacher,
"You are a helpful teacher.",
)).await;
director.register_agent(DirectorAgent::new(
AgentId::new(),
"Student",
AgentRole::Student,
"You are a curious student.",
)).await;
let agents = director.get_agents().await;
assert_eq!(agents.len(), 2);
// Teacher should be first (higher priority)
assert_eq!(agents[0].role, AgentRole::Teacher);
}
#[tokio::test]
async fn test_conversation_state() {
let mut state = ConversationState::new();
assert_eq!(state.turn, 0);
let agent1 = AgentId::new();
let agent2 = AgentId::new();
state.record_turn(agent1, "Hello".to_string());
assert_eq!(state.turn, 1);
assert_eq!(state.consecutive_turns, 1);
state.record_turn(agent1, "World".to_string());
assert_eq!(state.turn, 2);
assert_eq!(state.consecutive_turns, 2);
state.record_turn(agent2, "Goodbye".to_string());
assert_eq!(state.turn, 3);
assert_eq!(state.consecutive_turns, 1);
assert_eq!(state.current_speaker, Some(agent2));
}
#[tokio::test]
async fn test_select_next_speaker_priority() {
let config = DirectorConfig {
strategy: ScheduleStrategy::Priority,
..Default::default()
};
let director = Director::new(config);
let teacher_id = AgentId::new();
let student_id = AgentId::new();
director.register_agent(DirectorAgent::new(
teacher_id,
"Teacher",
AgentRole::Teacher,
"Teaching",
)).await;
director.register_agent(DirectorAgent::new(
student_id,
"Student",
AgentRole::Student,
"Learning",
)).await;
let speaker = director.select_next_speaker().await;
assert!(speaker.is_some());
assert_eq!(speaker.unwrap().role, AgentRole::Teacher);
}
#[tokio::test]
async fn test_director_builder() {
let director = DirectorBuilder::new()
.strategy(ScheduleStrategy::RoundRobin)
.max_turns(10)
.teacher(AgentId::new(), "AI Teacher", "You teach students.")
.student(AgentId::new(), "Curious Student", "You ask questions.")
.build()
.await;
let agents = director.get_agents().await;
assert_eq!(agents.len(), 2);
let state = director.get_state().await;
assert_eq!(state.turn, 0);
}
#[test]
fn test_agent_role_priority() {
assert_eq!(AgentRole::Teacher.default_priority(), 10);
assert_eq!(AgentRole::Assistant.default_priority(), 7);
assert_eq!(AgentRole::Student.default_priority(), 5);
assert_eq!(AgentRole::Observer.default_priority(), 0);
}
#[test]
fn test_agent_role_parse() {
assert_eq!(AgentRole::from_str("teacher"), Some(AgentRole::Teacher));
assert_eq!(AgentRole::from_str("STUDENT"), Some(AgentRole::Student));
assert_eq!(AgentRole::from_str("unknown"), None);
}
}