feat(ecc2): implement live output streaming per agent (#774)

- PTY output capture via tokio::process with stdout/stderr piping
- Ring buffer (1000 lines) per session
- Output pane wired to show selected session with auto-scroll
- Broadcast channel for output events

.gitignore

@@ -83,6 +83,9 @@ temp/
 *.bak
 *.backup
 
+# Rust build artifacts
+ecc2/target/
+
 # Bootstrap pipeline outputs
 # Generated lock files in tool subdirectories
 .opencode/package-lock.json

ecc2/Cargo.toml

@@ -0,0 +1,52 @@
+[package]
+name = "ecc-tui"
+version = "0.1.0"
+edition = "2021"
+description = "ECC 2.0 — Agentic IDE control plane with TUI dashboard"
+license = "MIT"
+authors = ["Affaan Mustafa <me@affaanmustafa.com>"]
+repository = "https://github.com/affaan-m/everything-claude-code"
+
+[dependencies]
+# TUI
+ratatui = "0.29"
+crossterm = "0.28"
+
+# Async runtime
+tokio = { version = "1", features = ["full"] }
+
+# State store
+rusqlite = { version = "0.32", features = ["bundled"] }
+
+# Git integration
+git2 = "0.19"
+
+# Serialization
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+toml = "0.8"
+
+# CLI
+clap = { version = "4", features = ["derive"] }
+
+# Logging & tracing
+tracing = "0.1"
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+
+# Error handling
+anyhow = "1"
+thiserror = "2"
+
+# Time
+chrono = { version = "0.4", features = ["serde"] }
+
+# UUID for session IDs
+uuid = { version = "1", features = ["v4"] }
+
+# Directory paths
+dirs = "6"
+
+[profile.release]
+lto = true
+codegen-units = 1
+strip = true

ecc2/src/comms/mod.rs

@@ -0,0 +1,33 @@
+use anyhow::Result;
+use serde::{Deserialize, Serialize};
+
+use crate::session::store::StateStore;
+
+/// Message types for inter-agent communication.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum MessageType {
+    /// Task handoff from one agent to another
+    TaskHandoff { task: String, context: String },
+    /// Agent requesting information from another
+    Query { question: String },
+    /// Response to a query
+    Response { answer: String },
+    /// Notification of completion
+    Completed { summary: String, files_changed: Vec<String> },
+    /// Conflict detected (e.g., two agents editing the same file)
+    Conflict { file: String, description: String },
+}
+
+/// Send a structured message between sessions.
+pub fn send(db: &StateStore, from: &str, to: &str, msg: &MessageType) -> Result<()> {
+    let content = serde_json::to_string(msg)?;
+    let msg_type = match msg {
+        MessageType::TaskHandoff { .. } => "task_handoff",
+        MessageType::Query { .. } => "query",
+        MessageType::Response { .. } => "response",
+        MessageType::Completed { .. } => "completed",
+        MessageType::Conflict { .. } => "conflict",
+    };
+    db.send_message(from, to, &content, msg_type)?;
+    Ok(())
+}

ecc2/src/config/mod.rs

@@ -0,0 +1,54 @@
+use anyhow::Result;
+use serde::{Deserialize, Serialize};
+use std::path::PathBuf;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Config {
+    pub db_path: PathBuf,
+    pub worktree_root: PathBuf,
+    pub max_parallel_sessions: usize,
+    pub max_parallel_worktrees: usize,
+    pub session_timeout_secs: u64,
+    pub heartbeat_interval_secs: u64,
+    pub default_agent: String,
+    pub theme: Theme,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub enum Theme {
+    Dark,
+    Light,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        let home = dirs::home_dir().unwrap_or_else(|| PathBuf::from("."));
+        Self {
+            db_path: home.join(".claude").join("ecc2.db"),
+            worktree_root: PathBuf::from("/tmp/ecc-worktrees"),
+            max_parallel_sessions: 8,
+            max_parallel_worktrees: 6,
+            session_timeout_secs: 3600,
+            heartbeat_interval_secs: 30,
+            default_agent: "claude".to_string(),
+            theme: Theme::Dark,
+        }
+    }
+}
+
+impl Config {
+    pub fn load() -> Result<Self> {
+        let config_path = dirs::home_dir()
+            .unwrap_or_else(|| PathBuf::from("."))
+            .join(".claude")
+            .join("ecc2.toml");
+
+        if config_path.exists() {
+            let content = std::fs::read_to_string(&config_path)?;
+            let config: Config = toml::from_str(&content)?;
+            Ok(config)
+        } else {
+            Ok(Config::default())
+        }
+    }
+}

ecc2/src/main.rs

@@ -0,0 +1,94 @@
+mod config;
+mod session;
+mod tui;
+mod worktree;
+mod observability;
+mod comms;
+
+use anyhow::Result;
+use clap::Parser;
+use tracing_subscriber::EnvFilter;
+
+#[derive(Parser, Debug)]
+#[command(name = "ecc", version, about = "ECC 2.0 — Agentic IDE control plane")]
+struct Cli {
+    #[command(subcommand)]
+    command: Option<Commands>,
+}
+
+#[derive(clap::Subcommand, Debug)]
+enum Commands {
+    /// Launch the TUI dashboard
+    Dashboard,
+    /// Start a new agent session
+    Start {
+        /// Task description for the agent
+        #[arg(short, long)]
+        task: String,
+        /// Agent type (claude, codex, custom)
+        #[arg(short, long, default_value = "claude")]
+        agent: String,
+        /// Create a dedicated worktree for this session
+        #[arg(short, long)]
+        worktree: bool,
+    },
+    /// List active sessions
+    Sessions,
+    /// Show session details
+    Status {
+        /// Session ID or alias
+        session_id: Option<String>,
+    },
+    /// Stop a running session
+    Stop {
+        /// Session ID or alias
+        session_id: String,
+    },
+    /// Run as background daemon
+    Daemon,
+}
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    tracing_subscriber::fmt()
+        .with_env_filter(EnvFilter::from_default_env())
+        .init();
+
+    let cli = Cli::parse();
+
+    let cfg = config::Config::load()?;
+    let db = session::store::StateStore::open(&cfg.db_path)?;
+
+    match cli.command {
+        Some(Commands::Dashboard) | None => {
+            tui::app::run(db, cfg).await?;
+        }
+        Some(Commands::Start { task, agent, worktree: use_worktree }) => {
+            let session_id = session::manager::create_session(
+                &db, &cfg, &task, &agent, use_worktree,
+            ).await?;
+            println!("Session started: {session_id}");
+        }
+        Some(Commands::Sessions) => {
+            let sessions = session::manager::list_sessions(&db)?;
+            for s in sessions {
+                println!("{} [{}] {}", s.id, s.state, s.task);
+            }
+        }
+        Some(Commands::Status { session_id }) => {
+            let id = session_id.unwrap_or_else(|| "latest".to_string());
+            let status = session::manager::get_status(&db, &id)?;
+            println!("{status}");
+        }
+        Some(Commands::Stop { session_id }) => {
+            session::manager::stop_session(&db, &session_id).await?;
+            println!("Session stopped: {session_id}");
+        }
+        Some(Commands::Daemon) => {
+            println!("Starting ECC daemon...");
+            session::daemon::run(db, cfg).await?;
+        }
+    }
+
+    Ok(())
+}

ecc2/src/observability/mod.rs

@@ -0,0 +1,54 @@
+use anyhow::Result;
+use serde::{Deserialize, Serialize};
+
+use crate::session::store::StateStore;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ToolCallEvent {
+    pub session_id: String,
+    pub tool_name: String,
+    pub input_summary: String,
+    pub output_summary: String,
+    pub duration_ms: u64,
+    pub risk_score: f64,
+}
+
+impl ToolCallEvent {
+    /// Compute risk score based on tool type and input patterns.
+    pub fn compute_risk(tool_name: &str, input: &str) -> f64 {
+        let mut score: f64 = 0.0;
+
+        // Destructive tools get higher base risk
+        match tool_name {
+            "Bash" => score += 0.3,
+            "Write" => score += 0.2,
+            "Edit" => score += 0.1,
+            _ => score += 0.05,
+        }
+
+        // Dangerous patterns in bash commands
+        if tool_name == "Bash" {
+            if input.contains("rm -rf") || input.contains("--force") {
+                score += 0.4;
+            }
+            if input.contains("git push") || input.contains("git reset") {
+                score += 0.3;
+            }
+            if input.contains("sudo") || input.contains("chmod 777") {
+                score += 0.5;
+            }
+        }
+
+        score.min(1.0)
+    }
+}
+
+pub fn log_tool_call(db: &StateStore, event: &ToolCallEvent) -> Result<()> {
+    db.send_message(
+        &event.session_id,
+        "observability",
+        &serde_json::to_string(event)?,
+        "tool_call",
+    )?;
+    Ok(())
+}

ecc2/src/session/daemon.rs

@@ -0,0 +1,46 @@
+use anyhow::Result;
+use std::time::Duration;
+use tokio::time;
+
+use super::store::StateStore;
+use super::SessionState;
+use crate::config::Config;
+
+/// Background daemon that monitors sessions, handles heartbeats,
+/// and cleans up stale resources.
+pub async fn run(db: StateStore, cfg: Config) -> Result<()> {
+    tracing::info!("ECC daemon started");
+
+    let heartbeat_interval = Duration::from_secs(cfg.heartbeat_interval_secs);
+    let timeout = Duration::from_secs(cfg.session_timeout_secs);
+
+    loop {
+        if let Err(e) = check_sessions(&db, timeout) {
+            tracing::error!("Session check failed: {e}");
+        }
+
+        time::sleep(heartbeat_interval).await;
+    }
+}
+
+fn check_sessions(db: &StateStore, timeout: Duration) -> Result<()> {
+    let sessions = db.list_sessions()?;
+
+    for session in sessions {
+        if session.state != SessionState::Running {
+            continue;
+        }
+
+        let elapsed = chrono::Utc::now()
+            .signed_duration_since(session.updated_at)
+            .to_std()
+            .unwrap_or(Duration::ZERO);
+
+        if elapsed > timeout {
+            tracing::warn!("Session {} timed out after {:?}", session.id, elapsed);
+            db.update_state(&session.id, &SessionState::Failed)?;
+        }
+    }
+
+    Ok(())
+}

ecc2/src/session/manager.rs

@@ -0,0 +1,76 @@
+use anyhow::Result;
+use std::fmt;
+
+use super::{Session, SessionMetrics, SessionState};
+use super::store::StateStore;
+use crate::config::Config;
+use crate::worktree;
+
+pub async fn create_session(
+    db: &StateStore,
+    cfg: &Config,
+    task: &str,
+    agent_type: &str,
+    use_worktree: bool,
+) -> Result<String> {
+    let id = uuid::Uuid::new_v4().to_string()[..8].to_string();
+    let now = chrono::Utc::now();
+
+    let wt = if use_worktree {
+        Some(worktree::create_for_session(&id, cfg)?)
+    } else {
+        None
+    };
+
+    let session = Session {
+        id: id.clone(),
+        task: task.to_string(),
+        agent_type: agent_type.to_string(),
+        state: SessionState::Pending,
+        worktree: wt,
+        created_at: now,
+        updated_at: now,
+        metrics: SessionMetrics::default(),
+    };
+
+    db.insert_session(&session)?;
+    Ok(id)
+}
+
+pub fn list_sessions(db: &StateStore) -> Result<Vec<Session>> {
+    db.list_sessions()
+}
+
+pub fn get_status(db: &StateStore, id: &str) -> Result<SessionStatus> {
+    let session = db
+        .get_session(id)?
+        .ok_or_else(|| anyhow::anyhow!("Session not found: {id}"))?;
+    Ok(SessionStatus(session))
+}
+
+pub async fn stop_session(db: &StateStore, id: &str) -> Result<()> {
+    db.update_state(id, &SessionState::Stopped)?;
+    Ok(())
+}
+
+pub struct SessionStatus(Session);
+
+impl fmt::Display for SessionStatus {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let s = &self.0;
+        writeln!(f, "Session: {}", s.id)?;
+        writeln!(f, "Task:    {}", s.task)?;
+        writeln!(f, "Agent:   {}", s.agent_type)?;
+        writeln!(f, "State:   {}", s.state)?;
+        if let Some(ref wt) = s.worktree {
+            writeln!(f, "Branch:  {}", wt.branch)?;
+            writeln!(f, "Worktree: {}", wt.path.display())?;
+        }
+        writeln!(f, "Tokens:  {}", s.metrics.tokens_used)?;
+        writeln!(f, "Tools:   {}", s.metrics.tool_calls)?;
+        writeln!(f, "Files:   {}", s.metrics.files_changed)?;
+        writeln!(f, "Cost:    ${:.4}", s.metrics.cost_usd)?;
+        writeln!(f, "Created: {}", s.created_at)?;
+        write!(f, "Updated: {}", s.updated_at)
+    }
+}

ecc2/src/session/mod.rs

@@ -0,0 +1,61 @@
+pub mod daemon;
+pub mod manager;
+pub mod output;
+pub mod runtime;
+pub mod store;
+
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+use std::fmt;
+use std::path::PathBuf;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Session {
+    pub id: String,
+    pub task: String,
+    pub agent_type: String,
+    pub state: SessionState,
+    pub worktree: Option<WorktreeInfo>,
+    pub created_at: DateTime<Utc>,
+    pub updated_at: DateTime<Utc>,
+    pub metrics: SessionMetrics,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub enum SessionState {
+    Pending,
+    Running,
+    Idle,
+    Completed,
+    Failed,
+    Stopped,
+}
+
+impl fmt::Display for SessionState {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            SessionState::Pending => write!(f, "pending"),
+            SessionState::Running => write!(f, "running"),
+            SessionState::Idle => write!(f, "idle"),
+            SessionState::Completed => write!(f, "completed"),
+            SessionState::Failed => write!(f, "failed"),
+            SessionState::Stopped => write!(f, "stopped"),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct WorktreeInfo {
+    pub path: PathBuf,
+    pub branch: String,
+    pub base_branch: String,
+}
+
+#[derive(Debug, Clone, Default, Serialize, Deserialize)]
+pub struct SessionMetrics {
+    pub tokens_used: u64,
+    pub tool_calls: u64,
+    pub files_changed: u32,
+    pub duration_secs: u64,
+    pub cost_usd: f64,
+}

ecc2/src/session/output.rs

@@ -0,0 +1,149 @@
+use std::collections::{HashMap, VecDeque};
+use std::sync::{Arc, Mutex, MutexGuard};
+
+use serde::{Deserialize, Serialize};
+use tokio::sync::broadcast;
+
+pub const OUTPUT_BUFFER_LIMIT: usize = 1000;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+pub enum OutputStream {
+    Stdout,
+    Stderr,
+}
+
+impl OutputStream {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            Self::Stdout => "stdout",
+            Self::Stderr => "stderr",
+        }
+    }
+
+    pub fn from_db_value(value: &str) -> Self {
+        match value {
+            "stderr" => Self::Stderr,
+            _ => Self::Stdout,
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+pub struct OutputLine {
+    pub stream: OutputStream,
+    pub text: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct OutputEvent {
+    pub session_id: String,
+    pub line: OutputLine,
+}
+
+#[derive(Clone)]
+pub struct SessionOutputStore {
+    capacity: usize,
+    buffers: Arc<Mutex<HashMap<String, VecDeque<OutputLine>>>>,
+    tx: broadcast::Sender<OutputEvent>,
+}
+
+impl Default for SessionOutputStore {
+    fn default() -> Self {
+        Self::new(OUTPUT_BUFFER_LIMIT)
+    }
+}
+
+impl SessionOutputStore {
+    pub fn new(capacity: usize) -> Self {
+        let capacity = capacity.max(1);
+        let (tx, _) = broadcast::channel(capacity.max(16));
+
+        Self {
+            capacity,
+            buffers: Arc::new(Mutex::new(HashMap::new())),
+            tx,
+        }
+    }
+
+    pub fn subscribe(&self) -> broadcast::Receiver<OutputEvent> {
+        self.tx.subscribe()
+    }
+
+    pub fn push_line(&self, session_id: &str, stream: OutputStream, text: impl Into<String>) {
+        let line = OutputLine {
+            stream,
+            text: text.into(),
+        };
+
+        {
+            let mut buffers = self.lock_buffers();
+            let buffer = buffers.entry(session_id.to_string()).or_default();
+            buffer.push_back(line.clone());
+
+            while buffer.len() > self.capacity {
+                let _ = buffer.pop_front();
+            }
+        }
+
+        let _ = self.tx.send(OutputEvent {
+            session_id: session_id.to_string(),
+            line,
+        });
+    }
+
+    pub fn replace_lines(&self, session_id: &str, lines: Vec<OutputLine>) {
+        let mut buffer: VecDeque<OutputLine> = lines.into_iter().collect();
+
+        while buffer.len() > self.capacity {
+            let _ = buffer.pop_front();
+        }
+
+        self.lock_buffers().insert(session_id.to_string(), buffer);
+    }
+
+    pub fn lines(&self, session_id: &str) -> Vec<OutputLine> {
+        self.lock_buffers()
+            .get(session_id)
+            .map(|buffer| buffer.iter().cloned().collect())
+            .unwrap_or_default()
+    }
+
+    fn lock_buffers(&self) -> MutexGuard<'_, HashMap<String, VecDeque<OutputLine>>> {
+        self.buffers
+            .lock()
+            .unwrap_or_else(|poisoned| poisoned.into_inner())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{OutputStream, SessionOutputStore};
+
+    #[test]
+    fn ring_buffer_keeps_most_recent_lines() {
+        let store = SessionOutputStore::new(3);
+
+        store.push_line("session-1", OutputStream::Stdout, "line-1");
+        store.push_line("session-1", OutputStream::Stdout, "line-2");
+        store.push_line("session-1", OutputStream::Stdout, "line-3");
+        store.push_line("session-1", OutputStream::Stdout, "line-4");
+
+        let lines = store.lines("session-1");
+        let texts: Vec<_> = lines.iter().map(|line| line.text.as_str()).collect();
+
+        assert_eq!(texts, vec!["line-2", "line-3", "line-4"]);
+    }
+
+    #[tokio::test]
+    async fn pushing_output_broadcasts_events() {
+        let store = SessionOutputStore::new(8);
+        let mut rx = store.subscribe();
+
+        store.push_line("session-1", OutputStream::Stderr, "problem");
+
+        let event = rx.recv().await.expect("broadcast event");
+        assert_eq!(event.session_id, "session-1");
+        assert_eq!(event.line.stream, OutputStream::Stderr);
+        assert_eq!(event.line.text, "problem");
+    }
+}

ecc2/src/session/runtime.rs

@@ -0,0 +1,176 @@
+use std::path::{Path, PathBuf};
+use std::process::ExitStatus;
+use std::process::Stdio;
+
+use anyhow::{Context, Result};
+use tokio::io::{AsyncBufReadExt, AsyncRead, BufReader};
+use tokio::process::Command;
+
+use super::output::{OutputStream, SessionOutputStore};
+use super::store::StateStore;
+use super::SessionState;
+
+pub async fn capture_command_output(
+    db_path: PathBuf,
+    session_id: String,
+    mut command: Command,
+    output_store: SessionOutputStore,
+) -> Result<ExitStatus> {
+    let result = async {
+        let mut child = command
+            .stdout(Stdio::piped())
+            .stderr(Stdio::piped())
+            .spawn()
+            .with_context(|| format!("Failed to start process for session {}", session_id))?;
+
+        update_session_state(&db_path, &session_id, SessionState::Running)?;
+
+        let stdout = child.stdout.take().context("Child stdout was not piped")?;
+        let stderr = child.stderr.take().context("Child stderr was not piped")?;
+
+        let stdout_task = tokio::spawn(capture_stream(
+            db_path.clone(),
+            session_id.clone(),
+            stdout,
+            OutputStream::Stdout,
+            output_store.clone(),
+        ));
+        let stderr_task = tokio::spawn(capture_stream(
+            db_path.clone(),
+            session_id.clone(),
+            stderr,
+            OutputStream::Stderr,
+            output_store,
+        ));
+
+        let status = child.wait().await?;
+        stdout_task.await??;
+        stderr_task.await??;
+
+        let final_state = if status.success() {
+            SessionState::Completed
+        } else {
+            SessionState::Failed
+        };
+        update_session_state(&db_path, &session_id, final_state)?;
+
+        Ok(status)
+    }
+    .await;
+
+    if result.is_err() {
+        let _ = update_session_state(&db_path, &session_id, SessionState::Failed);
+    }
+
+    result
+}
+
+async fn capture_stream<R>(
+    db_path: PathBuf,
+    session_id: String,
+    reader: R,
+    stream: OutputStream,
+    output_store: SessionOutputStore,
+) -> Result<()>
+where
+    R: AsyncRead + Unpin,
+{
+    let mut lines = BufReader::new(reader).lines();
+
+    while let Some(line) = lines.next_line().await? {
+        output_store.push_line(&session_id, stream, line.clone());
+        append_output_line(&db_path, &session_id, stream, &line)?;
+    }
+
+    Ok(())
+}
+
+fn append_output_line(
+    db_path: &Path,
+    session_id: &str,
+    stream: OutputStream,
+    line: &str,
+) -> Result<()> {
+    let db = StateStore::open(db_path)?;
+    db.append_output_line(session_id, stream, line)?;
+    Ok(())
+}
+
+fn update_session_state(db_path: &Path, session_id: &str, state: SessionState) -> Result<()> {
+    let db = StateStore::open(db_path)?;
+    db.update_state(session_id, &state)?;
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use std::collections::HashSet;
+    use std::env;
+
+    use anyhow::Result;
+    use chrono::Utc;
+    use tokio::process::Command;
+    use uuid::Uuid;
+
+    use super::capture_command_output;
+    use crate::session::output::{SessionOutputStore, OUTPUT_BUFFER_LIMIT};
+    use crate::session::store::StateStore;
+    use crate::session::{Session, SessionMetrics, SessionState};
+
+    #[tokio::test]
+    async fn capture_command_output_persists_lines_and_events() -> Result<()> {
+        let db_path = env::temp_dir().join(format!("ecc2-runtime-{}.db", Uuid::new_v4()));
+        let db = StateStore::open(&db_path)?;
+        let session_id = "session-1".to_string();
+        let now = Utc::now();
+
+        db.insert_session(&Session {
+            id: session_id.clone(),
+            task: "stream output".to_string(),
+            agent_type: "test".to_string(),
+            state: SessionState::Pending,
+            worktree: None,
+            created_at: now,
+            updated_at: now,
+            metrics: SessionMetrics::default(),
+        })?;
+
+        let output_store = SessionOutputStore::default();
+        let mut rx = output_store.subscribe();
+        let mut command = Command::new("/bin/sh");
+        command
+            .arg("-c")
+            .arg("printf 'alpha\\n'; printf 'beta\\n' >&2");
+
+        let status =
+            capture_command_output(db_path.clone(), session_id.clone(), command, output_store)
+                .await?;
+
+        assert!(status.success());
+
+        let db = StateStore::open(&db_path)?;
+        let session = db
+            .get_session(&session_id)?
+            .expect("session should still exist");
+        assert_eq!(session.state, SessionState::Completed);
+
+        let lines = db.get_output_lines(&session_id, OUTPUT_BUFFER_LIMIT)?;
+        let texts: HashSet<_> = lines.iter().map(|line| line.text.as_str()).collect();
+        assert_eq!(lines.len(), 2);
+        assert!(texts.contains("alpha"));
+        assert!(texts.contains("beta"));
+
+        let mut events = Vec::new();
+        while let Ok(event) = rx.try_recv() {
+            events.push(event.line.text);
+        }
+
+        assert_eq!(events.len(), 2);
+        assert!(events.iter().any(|line| line == "alpha"));
+        assert!(events.iter().any(|line| line == "beta"));
+
+        let _ = std::fs::remove_file(db_path);
+
+        Ok(())
+    }
+}

ecc2/src/session/store.rs

@@ -0,0 +1,309 @@
+use anyhow::Result;
+use rusqlite::Connection;
+use std::path::Path;
+use std::time::Duration;
+
+use super::output::{OutputLine, OutputStream, OUTPUT_BUFFER_LIMIT};
+use super::{Session, SessionMetrics, SessionState};
+
+pub struct StateStore {
+    conn: Connection,
+}
+
+impl StateStore {
+    pub fn open(path: &Path) -> Result<Self> {
+        let conn = Connection::open(path)?;
+        conn.busy_timeout(Duration::from_secs(5))?;
+        let store = Self { conn };
+        store.init_schema()?;
+        Ok(store)
+    }
+
+    fn init_schema(&self) -> Result<()> {
+        self.conn.execute_batch(
+            "
+            CREATE TABLE IF NOT EXISTS sessions (
+                id TEXT PRIMARY KEY,
+                task TEXT NOT NULL,
+                agent_type TEXT NOT NULL,
+                state TEXT NOT NULL DEFAULT 'pending',
+                worktree_path TEXT,
+                worktree_branch TEXT,
+                worktree_base TEXT,
+                tokens_used INTEGER DEFAULT 0,
+                tool_calls INTEGER DEFAULT 0,
+                files_changed INTEGER DEFAULT 0,
+                duration_secs INTEGER DEFAULT 0,
+                cost_usd REAL DEFAULT 0.0,
+                created_at TEXT NOT NULL,
+                updated_at TEXT NOT NULL
+            );
+
+            CREATE TABLE IF NOT EXISTS tool_log (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                session_id TEXT NOT NULL REFERENCES sessions(id),
+                tool_name TEXT NOT NULL,
+                input_summary TEXT,
+                output_summary TEXT,
+                duration_ms INTEGER,
+                risk_score REAL DEFAULT 0.0,
+                timestamp TEXT NOT NULL
+            );
+
+            CREATE TABLE IF NOT EXISTS messages (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                from_session TEXT NOT NULL,
+                to_session TEXT NOT NULL,
+                content TEXT NOT NULL,
+                msg_type TEXT NOT NULL DEFAULT 'info',
+                read INTEGER DEFAULT 0,
+                timestamp TEXT NOT NULL
+            );
+
+            CREATE TABLE IF NOT EXISTS session_output (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                session_id TEXT NOT NULL REFERENCES sessions(id),
+                stream TEXT NOT NULL,
+                line TEXT NOT NULL,
+                timestamp TEXT NOT NULL
+            );
+
+            CREATE INDEX IF NOT EXISTS idx_sessions_state ON sessions(state);
+            CREATE INDEX IF NOT EXISTS idx_tool_log_session ON tool_log(session_id);
+            CREATE INDEX IF NOT EXISTS idx_messages_to ON messages(to_session, read);
+            CREATE INDEX IF NOT EXISTS idx_session_output_session
+                ON session_output(session_id, id);
+            ",
+        )?;
+        Ok(())
+    }
+
+    pub fn insert_session(&self, session: &Session) -> Result<()> {
+        self.conn.execute(
+            "INSERT INTO sessions (id, task, agent_type, state, worktree_path, worktree_branch, worktree_base, created_at, updated_at)
+             VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9)",
+            rusqlite::params![
+                session.id,
+                session.task,
+                session.agent_type,
+                session.state.to_string(),
+                session.worktree.as_ref().map(|w| w.path.to_string_lossy().to_string()),
+                session.worktree.as_ref().map(|w| w.branch.clone()),
+                session.worktree.as_ref().map(|w| w.base_branch.clone()),
+                session.created_at.to_rfc3339(),
+                session.updated_at.to_rfc3339(),
+            ],
+        )?;
+        Ok(())
+    }
+
+    pub fn update_state(&self, session_id: &str, state: &SessionState) -> Result<()> {
+        self.conn.execute(
+            "UPDATE sessions SET state = ?1, updated_at = ?2 WHERE id = ?3",
+            rusqlite::params![
+                state.to_string(),
+                chrono::Utc::now().to_rfc3339(),
+                session_id,
+            ],
+        )?;
+        Ok(())
+    }
+
+    pub fn update_metrics(&self, session_id: &str, metrics: &SessionMetrics) -> Result<()> {
+        self.conn.execute(
+            "UPDATE sessions SET tokens_used = ?1, tool_calls = ?2, files_changed = ?3, duration_secs = ?4, cost_usd = ?5, updated_at = ?6 WHERE id = ?7",
+            rusqlite::params![
+                metrics.tokens_used,
+                metrics.tool_calls,
+                metrics.files_changed,
+                metrics.duration_secs,
+                metrics.cost_usd,
+                chrono::Utc::now().to_rfc3339(),
+                session_id,
+            ],
+        )?;
+        Ok(())
+    }
+
+    pub fn list_sessions(&self) -> Result<Vec<Session>> {
+        let mut stmt = self.conn.prepare(
+            "SELECT id, task, agent_type, state, worktree_path, worktree_branch, worktree_base,
+                    tokens_used, tool_calls, files_changed, duration_secs, cost_usd,
+                    created_at, updated_at
+             FROM sessions ORDER BY updated_at DESC",
+        )?;
+
+        let sessions = stmt
+            .query_map([], |row| {
+                let state_str: String = row.get(3)?;
+                let state = match state_str.as_str() {
+                    "running" => SessionState::Running,
+                    "idle" => SessionState::Idle,
+                    "completed" => SessionState::Completed,
+                    "failed" => SessionState::Failed,
+                    "stopped" => SessionState::Stopped,
+                    _ => SessionState::Pending,
+                };
+
+                let worktree_path: Option<String> = row.get(4)?;
+                let worktree = worktree_path.map(|p| super::WorktreeInfo {
+                    path: std::path::PathBuf::from(p),
+                    branch: row.get::<_, String>(5).unwrap_or_default(),
+                    base_branch: row.get::<_, String>(6).unwrap_or_default(),
+                });
+
+                let created_str: String = row.get(12)?;
+                let updated_str: String = row.get(13)?;
+
+                Ok(Session {
+                    id: row.get(0)?,
+                    task: row.get(1)?,
+                    agent_type: row.get(2)?,
+                    state,
+                    worktree,
+                    created_at: chrono::DateTime::parse_from_rfc3339(&created_str)
+                        .unwrap_or_default()
+                        .with_timezone(&chrono::Utc),
+                    updated_at: chrono::DateTime::parse_from_rfc3339(&updated_str)
+                        .unwrap_or_default()
+                        .with_timezone(&chrono::Utc),
+                    metrics: SessionMetrics {
+                        tokens_used: row.get(7)?,
+                        tool_calls: row.get(8)?,
+                        files_changed: row.get(9)?,
+                        duration_secs: row.get(10)?,
+                        cost_usd: row.get(11)?,
+                    },
+                })
+            })?
+            .collect::<Result<Vec<_>, _>>()?;
+
+        Ok(sessions)
+    }
+
+    pub fn get_session(&self, id: &str) -> Result<Option<Session>> {
+        let sessions = self.list_sessions()?;
+        Ok(sessions
+            .into_iter()
+            .find(|s| s.id == id || s.id.starts_with(id)))
+    }
+
+    pub fn send_message(&self, from: &str, to: &str, content: &str, msg_type: &str) -> Result<()> {
+        self.conn.execute(
+            "INSERT INTO messages (from_session, to_session, content, msg_type, timestamp)
+             VALUES (?1, ?2, ?3, ?4, ?5)",
+            rusqlite::params![from, to, content, msg_type, chrono::Utc::now().to_rfc3339()],
+        )?;
+        Ok(())
+    }
+
+    pub fn append_output_line(
+        &self,
+        session_id: &str,
+        stream: OutputStream,
+        line: &str,
+    ) -> Result<()> {
+        let now = chrono::Utc::now().to_rfc3339();
+
+        self.conn.execute(
+            "INSERT INTO session_output (session_id, stream, line, timestamp)
+             VALUES (?1, ?2, ?3, ?4)",
+            rusqlite::params![session_id, stream.as_str(), line, now],
+        )?;
+
+        self.conn.execute(
+            "DELETE FROM session_output
+             WHERE session_id = ?1
+               AND id NOT IN (
+                   SELECT id
+                   FROM session_output
+                   WHERE session_id = ?1
+                   ORDER BY id DESC
+                   LIMIT ?2
+               )",
+            rusqlite::params![session_id, OUTPUT_BUFFER_LIMIT as i64],
+        )?;
+
+        self.conn.execute(
+            "UPDATE sessions SET updated_at = ?1 WHERE id = ?2",
+            rusqlite::params![chrono::Utc::now().to_rfc3339(), session_id],
+        )?;
+
+        Ok(())
+    }
+
+    pub fn get_output_lines(&self, session_id: &str, limit: usize) -> Result<Vec<OutputLine>> {
+        let mut stmt = self.conn.prepare(
+            "SELECT stream, line
+             FROM (
+                 SELECT id, stream, line
+                 FROM session_output
+                 WHERE session_id = ?1
+                 ORDER BY id DESC
+                 LIMIT ?2
+             )
+             ORDER BY id ASC",
+        )?;
+
+        let lines = stmt
+            .query_map(rusqlite::params![session_id, limit as i64], |row| {
+                let stream: String = row.get(0)?;
+                let text: String = row.get(1)?;
+
+                Ok(OutputLine {
+                    stream: OutputStream::from_db_value(&stream),
+                    text,
+                })
+            })?
+            .collect::<Result<Vec<_>, _>>()?;
+
+        Ok(lines)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::env;
+
+    use anyhow::Result;
+    use chrono::Utc;
+    use uuid::Uuid;
+
+    use super::StateStore;
+    use crate::session::output::{OutputStream, OUTPUT_BUFFER_LIMIT};
+    use crate::session::{Session, SessionMetrics, SessionState};
+
+    #[test]
+    fn append_output_line_keeps_latest_buffer_window() -> Result<()> {
+        let db_path = env::temp_dir().join(format!("ecc2-store-{}.db", Uuid::new_v4()));
+        let db = StateStore::open(&db_path)?;
+        let now = Utc::now();
+
+        db.insert_session(&Session {
+            id: "session-1".to_string(),
+            task: "buffer output".to_string(),
+            agent_type: "claude".to_string(),
+            state: SessionState::Running,
+            worktree: None,
+            created_at: now,
+            updated_at: now,
+            metrics: SessionMetrics::default(),
+        })?;
+
+        for index in 0..(OUTPUT_BUFFER_LIMIT + 5) {
+            db.append_output_line("session-1", OutputStream::Stdout, &format!("line-{index}"))?;
+        }
+
+        let lines = db.get_output_lines("session-1", OUTPUT_BUFFER_LIMIT)?;
+        let texts: Vec<_> = lines.iter().map(|line| line.text.as_str()).collect();
+
+        assert_eq!(lines.len(), OUTPUT_BUFFER_LIMIT);
+        assert_eq!(texts.first().copied(), Some("line-5"));
+        let expected_last_line = format!("line-{}", OUTPUT_BUFFER_LIMIT + 4);
+        assert_eq!(texts.last().copied(), Some(expected_last_line.as_str()));
+
+        let _ = std::fs::remove_file(db_path);
+
+        Ok(())
+    }
+}

ecc2/src/tui/app.rs

@@ -0,0 +1,52 @@
+use anyhow::Result;
+use crossterm::{
+    event::{self, Event, KeyCode, KeyModifiers},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+use ratatui::prelude::*;
+use std::io;
+use std::time::Duration;
+
+use super::dashboard::Dashboard;
+use crate::config::Config;
+use crate::session::store::StateStore;
+
+pub async fn run(db: StateStore, cfg: Config) -> Result<()> {
+    enable_raw_mode()?;
+    let mut stdout = io::stdout();
+    execute!(stdout, EnterAlternateScreen)?;
+
+    let backend = CrosstermBackend::new(stdout);
+    let mut terminal = Terminal::new(backend)?;
+
+    let mut dashboard = Dashboard::new(db, cfg);
+
+    loop {
+        terminal.draw(|frame| dashboard.render(frame))?;
+
+        if event::poll(Duration::from_millis(250))? {
+            if let Event::Key(key) = event::read()? {
+                match (key.modifiers, key.code) {
+                    (KeyModifiers::CONTROL, KeyCode::Char('c')) => break,
+                    (_, KeyCode::Char('q')) => break,
+                    (_, KeyCode::Tab) => dashboard.next_pane(),
+                    (KeyModifiers::SHIFT, KeyCode::BackTab) => dashboard.prev_pane(),
+                    (_, KeyCode::Char('j')) | (_, KeyCode::Down) => dashboard.scroll_down(),
+                    (_, KeyCode::Char('k')) | (_, KeyCode::Up) => dashboard.scroll_up(),
+                    (_, KeyCode::Char('n')) => dashboard.new_session(),
+                    (_, KeyCode::Char('s')) => dashboard.stop_selected(),
+                    (_, KeyCode::Char('r')) => dashboard.refresh(),
+                    (_, KeyCode::Char('?')) => dashboard.toggle_help(),
+                    _ => {}
+                }
+            }
+        }
+
+        dashboard.tick().await;
+    }
+
+    disable_raw_mode()?;
+    execute!(terminal.backend_mut(), LeaveAlternateScreen)?;
+    Ok(())
+}

ecc2/src/tui/dashboard.rs

@@ -0,0 +1,512 @@
+use std::collections::HashMap;
+
+use ratatui::{
+    prelude::*,
+    widgets::{Block, Borders, List, ListItem, Paragraph, Tabs},
+};
+use tokio::sync::broadcast;
+
+use crate::config::Config;
+use crate::session::output::{OutputEvent, OutputLine, SessionOutputStore, OUTPUT_BUFFER_LIMIT};
+use crate::session::store::StateStore;
+use crate::session::{Session, SessionState};
+
+pub struct Dashboard {
+    db: StateStore,
+    output_store: SessionOutputStore,
+    output_rx: broadcast::Receiver<OutputEvent>,
+    sessions: Vec<Session>,
+    session_output_cache: HashMap<String, Vec<OutputLine>>,
+    selected_pane: Pane,
+    selected_session: usize,
+    show_help: bool,
+    output_follow: bool,
+    output_scroll_offset: usize,
+    last_output_height: usize,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq)]
+enum Pane {
+    Sessions,
+    Output,
+    Metrics,
+}
+
+impl Dashboard {
+    pub fn new(db: StateStore, cfg: Config) -> Self {
+        Self::with_output_store(db, cfg, SessionOutputStore::default())
+    }
+
+    pub fn with_output_store(
+        db: StateStore,
+        _cfg: Config,
+        output_store: SessionOutputStore,
+    ) -> Self {
+        let sessions = db.list_sessions().unwrap_or_default();
+        let output_rx = output_store.subscribe();
+
+        let mut dashboard = Self {
+            db,
+            output_store,
+            output_rx,
+            sessions,
+            session_output_cache: HashMap::new(),
+            selected_pane: Pane::Sessions,
+            selected_session: 0,
+            show_help: false,
+            output_follow: true,
+            output_scroll_offset: 0,
+            last_output_height: 0,
+        };
+        dashboard.sync_selected_output();
+        dashboard
+    }
+
+    pub fn render(&mut self, frame: &mut Frame) {
+        let chunks = Layout::default()
+            .direction(Direction::Vertical)
+            .constraints([
+                Constraint::Length(3), // Header
+                Constraint::Min(10),   // Main content
+                Constraint::Length(3), // Status bar
+            ])
+            .split(frame.area());
+
+        self.render_header(frame, chunks[0]);
+
+        if self.show_help {
+            self.render_help(frame, chunks[1]);
+        } else {
+            let main_chunks = Layout::default()
+                .direction(Direction::Horizontal)
+                .constraints([
+                    Constraint::Percentage(35), // Session list
+                    Constraint::Percentage(65), // Output/details
+                ])
+                .split(chunks[1]);
+
+            self.render_sessions(frame, main_chunks[0]);
+
+            let right_chunks = Layout::default()
+                .direction(Direction::Vertical)
+                .constraints([
+                    Constraint::Percentage(70), // Output
+                    Constraint::Percentage(30), // Metrics
+                ])
+                .split(main_chunks[1]);
+
+            self.render_output(frame, right_chunks[0]);
+            self.render_metrics(frame, right_chunks[1]);
+        }
+
+        self.render_status_bar(frame, chunks[2]);
+    }
+
+    fn render_header(&self, frame: &mut Frame, area: Rect) {
+        let running = self
+            .sessions
+            .iter()
+            .filter(|s| s.state == SessionState::Running)
+            .count();
+        let total = self.sessions.len();
+
+        let title = format!(" ECC 2.0 | {running} running / {total} total ");
+        let tabs = Tabs::new(vec!["Sessions", "Output", "Metrics"])
+            .block(Block::default().borders(Borders::ALL).title(title))
+            .select(match self.selected_pane {
+                Pane::Sessions => 0,
+                Pane::Output => 1,
+                Pane::Metrics => 2,
+            })
+            .highlight_style(
+                Style::default()
+                    .fg(Color::Cyan)
+                    .add_modifier(Modifier::BOLD),
+            );
+
+        frame.render_widget(tabs, area);
+    }
+
+    fn render_sessions(&self, frame: &mut Frame, area: Rect) {
+        let items: Vec<ListItem> = self
+            .sessions
+            .iter()
+            .enumerate()
+            .map(|(i, s)| {
+                let state_icon = match s.state {
+                    SessionState::Running => "●",
+                    SessionState::Idle => "○",
+                    SessionState::Completed => "✓",
+                    SessionState::Failed => "✗",
+                    SessionState::Stopped => "■",
+                    SessionState::Pending => "◌",
+                };
+                let style = if i == self.selected_session {
+                    Style::default()
+                        .fg(Color::Cyan)
+                        .add_modifier(Modifier::BOLD)
+                } else {
+                    Style::default()
+                };
+                let text = format!(
+                    "{state_icon} {} [{}] {}",
+                    &s.id[..8.min(s.id.len())],
+                    s.agent_type,
+                    s.task
+                );
+                ListItem::new(text).style(style)
+            })
+            .collect();
+
+        let border_style = if self.selected_pane == Pane::Sessions {
+            Style::default().fg(Color::Cyan)
+        } else {
+            Style::default()
+        };
+
+        let list = List::new(items).block(
+            Block::default()
+                .borders(Borders::ALL)
+                .title(" Sessions ")
+                .border_style(border_style),
+        );
+        frame.render_widget(list, area);
+    }
+
+    fn render_output(&mut self, frame: &mut Frame, area: Rect) {
+        self.sync_output_scroll(area.height.saturating_sub(2) as usize);
+
+        let content = if self.sessions.get(self.selected_session).is_some() {
+            let lines = self.selected_output_lines();
+
+            if lines.is_empty() {
+                "Waiting for session output...".to_string()
+            } else {
+                lines
+                    .iter()
+                    .map(|line| line.text.as_str())
+                    .collect::<Vec<_>>()
+                    .join("\n")
+            }
+        } else {
+            "No sessions. Press 'n' to start one.".to_string()
+        };
+
+        let border_style = if self.selected_pane == Pane::Output {
+            Style::default().fg(Color::Cyan)
+        } else {
+            Style::default()
+        };
+
+        let paragraph = Paragraph::new(content)
+            .block(
+                Block::default()
+                    .borders(Borders::ALL)
+                    .title(" Output ")
+                    .border_style(border_style),
+            )
+            .scroll((self.output_scroll_offset as u16, 0));
+        frame.render_widget(paragraph, area);
+    }
+
+    fn render_metrics(&self, frame: &mut Frame, area: Rect) {
+        let content = if let Some(session) = self.sessions.get(self.selected_session) {
+            let m = &session.metrics;
+            format!(
+                "Tokens: {} | Tools: {} | Files: {} | Cost: ${:.4} | Duration: {}s",
+                m.tokens_used, m.tool_calls, m.files_changed, m.cost_usd, m.duration_secs
+            )
+        } else {
+            "No metrics available".to_string()
+        };
+
+        let border_style = if self.selected_pane == Pane::Metrics {
+            Style::default().fg(Color::Cyan)
+        } else {
+            Style::default()
+        };
+
+        let paragraph = Paragraph::new(content).block(
+            Block::default()
+                .borders(Borders::ALL)
+                .title(" Metrics ")
+                .border_style(border_style),
+        );
+        frame.render_widget(paragraph, area);
+    }
+
+    fn render_status_bar(&self, frame: &mut Frame, area: Rect) {
+        let text = " [n]ew session  [s]top  [Tab] switch pane  [j/k] scroll  [?] help  [q]uit ";
+        let paragraph = Paragraph::new(text)
+            .style(Style::default().fg(Color::DarkGray))
+            .block(Block::default().borders(Borders::ALL));
+        frame.render_widget(paragraph, area);
+    }
+
+    fn render_help(&self, frame: &mut Frame, area: Rect) {
+        let help = vec![
+            "Keyboard Shortcuts:",
+            "",
+            "  n       New session",
+            "  s       Stop selected session",
+            "  Tab     Next pane",
+            "  S-Tab   Previous pane",
+            "  j/↓     Scroll down",
+            "  k/↑     Scroll up",
+            "  r       Refresh",
+            "  ?       Toggle help",
+            "  q/C-c   Quit",
+        ];
+
+        let paragraph = Paragraph::new(help.join("\n")).block(
+            Block::default()
+                .borders(Borders::ALL)
+                .title(" Help ")
+                .border_style(Style::default().fg(Color::Yellow)),
+        );
+        frame.render_widget(paragraph, area);
+    }
+
+    pub fn next_pane(&mut self) {
+        self.selected_pane = match self.selected_pane {
+            Pane::Sessions => Pane::Output,
+            Pane::Output => Pane::Metrics,
+            Pane::Metrics => Pane::Sessions,
+        };
+    }
+
+    pub fn prev_pane(&mut self) {
+        self.selected_pane = match self.selected_pane {
+            Pane::Sessions => Pane::Metrics,
+            Pane::Output => Pane::Sessions,
+            Pane::Metrics => Pane::Output,
+        };
+    }
+
+    pub fn scroll_down(&mut self) {
+        if self.selected_pane == Pane::Sessions && !self.sessions.is_empty() {
+            self.selected_session = (self.selected_session + 1).min(self.sessions.len() - 1);
+            self.reset_output_view();
+            self.sync_selected_output();
+        } else if self.selected_pane == Pane::Output {
+            let max_scroll = self.max_output_scroll();
+
+            if self.output_follow {
+                return;
+            }
+
+            if self.output_scroll_offset >= max_scroll.saturating_sub(1) {
+                self.output_follow = true;
+                self.output_scroll_offset = max_scroll;
+            } else {
+                self.output_scroll_offset = self.output_scroll_offset.saturating_add(1);
+            }
+        }
+    }
+
+    pub fn scroll_up(&mut self) {
+        if self.selected_pane == Pane::Sessions {
+            self.selected_session = self.selected_session.saturating_sub(1);
+            self.reset_output_view();
+            self.sync_selected_output();
+        } else if self.selected_pane == Pane::Output {
+            if self.output_follow {
+                self.output_follow = false;
+                self.output_scroll_offset = self.max_output_scroll();
+            }
+
+            self.output_scroll_offset = self.output_scroll_offset.saturating_sub(1);
+        } else {
+            self.output_scroll_offset = self.output_scroll_offset.saturating_sub(1);
+        }
+    }
+
+    pub fn new_session(&mut self) {
+        // TODO: Open a dialog to create a new session
+        tracing::info!("New session dialog requested");
+    }
+
+    pub fn stop_selected(&mut self) {
+        if let Some(session) = self.sessions.get(self.selected_session) {
+            let _ = self.db.update_state(&session.id, &SessionState::Stopped);
+            self.refresh();
+        }
+    }
+
+    pub fn refresh(&mut self) {
+        self.sessions = self.db.list_sessions().unwrap_or_default();
+        self.clamp_selected_session();
+        self.sync_selected_output();
+    }
+
+    pub fn toggle_help(&mut self) {
+        self.show_help = !self.show_help;
+    }
+
+    pub async fn tick(&mut self) {
+        loop {
+            match self.output_rx.try_recv() {
+                Ok(_event) => {}
+                Err(broadcast::error::TryRecvError::Empty) => break,
+                Err(broadcast::error::TryRecvError::Lagged(_)) => continue,
+                Err(broadcast::error::TryRecvError::Closed) => break,
+            }
+        }
+
+        self.sessions = self.db.list_sessions().unwrap_or_default();
+        self.clamp_selected_session();
+        self.sync_selected_output();
+    }
+
+    fn clamp_selected_session(&mut self) {
+        if self.sessions.is_empty() {
+            self.selected_session = 0;
+        } else {
+            self.selected_session = self.selected_session.min(self.sessions.len() - 1);
+        }
+    }
+
+    fn sync_selected_output(&mut self) {
+        let Some(session_id) = self.selected_session_id().map(ToOwned::to_owned) else {
+            return;
+        };
+
+        match self.db.get_output_lines(&session_id, OUTPUT_BUFFER_LIMIT) {
+            Ok(lines) => {
+                self.output_store.replace_lines(&session_id, lines.clone());
+                self.session_output_cache.insert(session_id, lines);
+            }
+            Err(error) => {
+                tracing::warn!("Failed to load session output: {error}");
+            }
+        }
+    }
+
+    fn selected_session_id(&self) -> Option<&str> {
+        self.sessions
+            .get(self.selected_session)
+            .map(|session| session.id.as_str())
+    }
+
+    fn selected_output_lines(&self) -> &[OutputLine] {
+        self.selected_session_id()
+            .and_then(|session_id| self.session_output_cache.get(session_id))
+            .map(Vec::as_slice)
+            .unwrap_or(&[])
+    }
+
+    fn sync_output_scroll(&mut self, viewport_height: usize) {
+        self.last_output_height = viewport_height.max(1);
+        let max_scroll = self.max_output_scroll();
+
+        if self.output_follow {
+            self.output_scroll_offset = max_scroll;
+        } else {
+            self.output_scroll_offset = self.output_scroll_offset.min(max_scroll);
+        }
+    }
+
+    fn max_output_scroll(&self) -> usize {
+        self.selected_output_lines()
+            .len()
+            .saturating_sub(self.last_output_height.max(1))
+    }
+
+    fn reset_output_view(&mut self) {
+        self.output_follow = true;
+        self.output_scroll_offset = 0;
+    }
+
+    #[cfg(test)]
+    fn selected_output_text(&self) -> String {
+        self.selected_output_lines()
+            .iter()
+            .map(|line| line.text.clone())
+            .collect::<Vec<_>>()
+            .join("\n")
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::env;
+
+    use anyhow::Result;
+    use chrono::Utc;
+    use uuid::Uuid;
+
+    use super::{Dashboard, Pane};
+    use crate::config::Config;
+    use crate::session::output::OutputStream;
+    use crate::session::store::StateStore;
+    use crate::session::{Session, SessionMetrics, SessionState};
+
+    #[test]
+    fn refresh_loads_selected_session_output_and_follows_tail() -> Result<()> {
+        let db_path = env::temp_dir().join(format!("ecc2-dashboard-{}.db", Uuid::new_v4()));
+        let db = StateStore::open(&db_path)?;
+        let now = Utc::now();
+
+        db.insert_session(&Session {
+            id: "session-1".to_string(),
+            task: "tail output".to_string(),
+            agent_type: "claude".to_string(),
+            state: SessionState::Running,
+            worktree: None,
+            created_at: now,
+            updated_at: now,
+            metrics: SessionMetrics::default(),
+        })?;
+
+        for index in 0..12 {
+            db.append_output_line("session-1", OutputStream::Stdout, &format!("line {index}"))?;
+        }
+
+        let mut dashboard = Dashboard::new(db, Config::default());
+        dashboard.selected_pane = Pane::Output;
+        dashboard.refresh();
+        dashboard.sync_output_scroll(4);
+
+        assert_eq!(dashboard.output_scroll_offset, 8);
+        assert!(dashboard.selected_output_text().contains("line 11"));
+
+        let _ = std::fs::remove_file(db_path);
+
+        Ok(())
+    }
+
+    #[test]
+    fn scrolling_up_disables_follow_mode() -> Result<()> {
+        let db_path = env::temp_dir().join(format!("ecc2-dashboard-{}.db", Uuid::new_v4()));
+        let db = StateStore::open(&db_path)?;
+        let now = Utc::now();
+
+        db.insert_session(&Session {
+            id: "session-1".to_string(),
+            task: "inspect output".to_string(),
+            agent_type: "claude".to_string(),
+            state: SessionState::Running,
+            worktree: None,
+            created_at: now,
+            updated_at: now,
+            metrics: SessionMetrics::default(),
+        })?;
+
+        for index in 0..6 {
+            db.append_output_line("session-1", OutputStream::Stdout, &format!("line {index}"))?;
+        }
+
+        let mut dashboard = Dashboard::new(db, Config::default());
+        dashboard.selected_pane = Pane::Output;
+        dashboard.refresh();
+        dashboard.sync_output_scroll(3);
+        dashboard.scroll_up();
+
+        assert!(!dashboard.output_follow);
+        assert_eq!(dashboard.output_scroll_offset, 2);
+
+        let _ = std::fs::remove_file(db_path);
+
+        Ok(())
+    }
+}

ecc2/src/tui/mod.rs

@@ -0,0 +1,3 @@
+pub mod app;
+mod dashboard;
+mod widgets;

ecc2/src/tui/widgets.rs

@@ -0,0 +1,6 @@
+// Custom TUI widgets for ECC 2.0
+// TODO: Implement custom widgets:
+// - TokenMeter: visual token usage bar with budget threshold
+// - DiffViewer: side-by-side syntax-highlighted diff display
+// - ProgressTimeline: session timeline with tool call markers
+// - AgentTree: hierarchical view of parent/child agent sessions

ecc2/src/worktree/mod.rs

@@ -0,0 +1,80 @@
+use anyhow::{Context, Result};
+use std::path::PathBuf;
+use std::process::Command;
+
+use crate::config::Config;
+use crate::session::WorktreeInfo;
+
+/// Create a new git worktree for an agent session.
+pub fn create_for_session(session_id: &str, cfg: &Config) -> Result<WorktreeInfo> {
+    let branch = format!("ecc/{session_id}");
+    let path = cfg.worktree_root.join(session_id);
+
+    // Get current branch as base
+    let base = get_current_branch()?;
+
+    std::fs::create_dir_all(&cfg.worktree_root)
+        .context("Failed to create worktree root directory")?;
+
+    let output = Command::new("git")
+        .args(["worktree", "add", "-b", &branch])
+        .arg(&path)
+        .arg("HEAD")
+        .output()
+        .context("Failed to run git worktree add")?;
+
+    if !output.status.success() {
+        let stderr = String::from_utf8_lossy(&output.stderr);
+        anyhow::bail!("git worktree add failed: {stderr}");
+    }
+
+    tracing::info!("Created worktree at {} on branch {}", path.display(), branch);
+
+    Ok(WorktreeInfo {
+        path,
+        branch,
+        base_branch: base,
+    })
+}
+
+/// Remove a worktree and its branch.
+pub fn remove(path: &PathBuf) -> Result<()> {
+    let output = Command::new("git")
+        .args(["worktree", "remove", "--force"])
+        .arg(path)
+        .output()
+        .context("Failed to remove worktree")?;
+
+    if !output.status.success() {
+        let stderr = String::from_utf8_lossy(&output.stderr);
+        tracing::warn!("Worktree removal warning: {stderr}");
+    }
+
+    Ok(())
+}
+
+/// List all active worktrees.
+pub fn list() -> Result<Vec<String>> {
+    let output = Command::new("git")
+        .args(["worktree", "list", "--porcelain"])
+        .output()
+        .context("Failed to list worktrees")?;
+
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    let worktrees: Vec<String> = stdout
+        .lines()
+        .filter(|l| l.starts_with("worktree "))
+        .map(|l| l.trim_start_matches("worktree ").to_string())
+        .collect();
+
+    Ok(worktrees)
+}
+
+fn get_current_branch() -> Result<String> {
+    let output = Command::new("git")
+        .args(["rev-parse", "--abbrev-ref", "HEAD"])
+        .output()
+        .context("Failed to get current branch")?;
+
+    Ok(String::from_utf8_lossy(&output.stdout).trim().to_string())
+}