Add per-agent run stats (messages, tool calls by type)

compute_run_stats() walks the conversation AST after each agent
completes, counting messages and tool calls by tool name. Stats
are returned from save_agent_log(), stored on UnconsciousAgent,
and displayed in the agent list UI.

Co-Authored-By: Proof of Concept <poc@bcachefs.org>

src/mind/unconscious.rs

@@ -34,11 +34,12 @@ struct UnconsciousAgent {
     name: String,
     enabled: bool,
     auto: AutoAgent,
-    handle: Option<tokio::task::JoinHandle<(AutoAgent, Result<String, String>)>>,
+    handle: Option<tokio::task::JoinHandle<(AutoAgent, Result<String, String>, RunStats)>>,
     /// Shared agent handle — UI locks to read context live.
     pub agent: Option<std::sync::Arc<crate::agent::Agent>>,
     last_run: Option<Instant>,
     runs: usize,
+    last_stats: Option<RunStats>,
 }
 
 impl UnconsciousAgent {
@@ -60,6 +61,7 @@ pub struct UnconsciousSnapshot {
     pub runs: usize,
     pub last_run_secs_ago: Option<f64>,
     pub agent: Option<std::sync::Arc<crate::agent::Agent>>,
+    pub last_stats: Option<RunStats>,
 }
 
 pub struct Unconscious {
@@ -105,6 +107,7 @@ impl Unconscious {
                 agent: None,
                 last_run: None,
                 runs: 0,
+                last_stats: None,
             });
         }
         agents.sort_by(|a, b| a.name.cmp(&b.name));
@@ -144,6 +147,7 @@ impl Unconscious {
             runs: a.runs,
             last_run_secs_ago: a.last_run.map(|t| t.elapsed().as_secs_f64()),
             agent: a.agent.clone(),
+            last_stats: a.last_stats.clone(),
         }).collect()
     }
 
@@ -173,8 +177,9 @@ impl Unconscious {
                 agent.runs += 1;
                 // Get the AutoAgent back from the finished task
                 match handle.now_or_never() {
-                    Some(Ok((auto_back, result))) => {
+                    Some(Ok((auto_back, result, stats))) => {
                         agent.auto = auto_back;
+                        agent.last_stats = Some(stats);
                         match result {
                             Ok(_) => dbglog!("[unconscious] {} completed (run {})",
                                 agent.name, agent.runs),
@@ -289,30 +294,64 @@ impl Unconscious {
 
         self.agents[idx].handle = Some(tokio::spawn(async move {
             let result = auto.run_shared(&agent).await;
-            save_agent_log(&auto.name, &agent).await;
+            let stats = save_agent_log(&auto.name, &agent).await;
             auto.steps = orig_steps;
-            (auto, result)
+            (auto, result, stats)
         }));
     }
 }
 
-pub async fn save_agent_log(name: &str, agent: &std::sync::Arc<crate::agent::Agent>) {
+pub async fn save_agent_log(name: &str, agent: &std::sync::Arc<crate::agent::Agent>) -> RunStats {
     let dir = dirs::home_dir().unwrap_or_default()
         .join(format!(".consciousness/logs/{}", name));
-    if std::fs::create_dir_all(&dir).is_err() { return; }
-    let ts = chrono::Utc::now().format("%Y%m%d-%H%M%S");
-    let path = dir.join(format!("{}.json", ts));
-    let sections: serde_json::Value = {
-        let ctx = agent.context.lock().await;
-        serde_json::json!({
+    let ctx = agent.context.lock().await;
+    let stats = compute_run_stats(ctx.conversation());
+    if std::fs::create_dir_all(&dir).is_ok() {
+        let ts = chrono::Utc::now().format("%Y%m%d-%H%M%S");
+        let path = dir.join(format!("{}.json", ts));
+        let sections = serde_json::json!({
             "system": ctx.system(),
             "identity": ctx.identity(),
             "journal": ctx.journal(),
             "conversation": ctx.conversation(),
-        })
-    };
-    if let Ok(json) = serde_json::to_string_pretty(&sections) {
-        let _ = std::fs::write(&path, json);
-        dbglog!("[unconscious] saved log to {}", path.display());
+            "stats": stats,
+        });
+        if let Ok(json) = serde_json::to_string_pretty(&sections) {
+            let _ = std::fs::write(&path, json);
+        }
     }
+    dbglog!("[unconscious] {} — {} msgs, {} tool calls",
+        name, stats.messages, stats.tool_calls);
+    stats
+}
+
+#[derive(Clone, serde::Serialize)]
+pub struct RunStats {
+    pub messages: usize,
+    pub tool_calls: usize,
+    pub tool_calls_by_type: HashMap<String, usize>,
+}
+
+fn compute_run_stats(conversation: &[crate::agent::context::AstNode]) -> RunStats {
+    use crate::agent::context::{AstNode, NodeBody};
+
+    let mut messages = 0usize;
+    let mut tool_calls = 0usize;
+    let mut by_type: HashMap<String, usize> = HashMap::new();
+
+    for node in conversation {
+        if let AstNode::Branch { children, .. } = node {
+            messages += 1;
+            for child in children {
+                if let AstNode::Leaf(leaf) = child {
+                    if let NodeBody::ToolCall { name, .. } = leaf.body() {
+                        tool_calls += 1;
+                        *by_type.entry(name.to_string()).or_default() += 1;
+                    }
+                }
+            }
+        }
+    }
+
+    RunStats { messages, tool_calls, tool_calls_by_type: by_type }
 }

src/user/subconscious.rs

@@ -250,6 +250,10 @@ impl SubconsciousScreen {
                     format!("run {}", snap.runs + 1)
                 } else if !snap.enabled {
                     "off".to_string()
+                } else if let Some(ref stats) = snap.last_stats {
+                    format!("×{} {} {}msg {}tc",
+                        snap.runs, ago,
+                        stats.messages, stats.tool_calls)
                 } else {
                     format!("×{} {}", snap.runs, ago)
                 };