agent visits: track when agents successfully process nodes

New append-only visits.capnp log records which agent processed which
node and when. Only recorded on successful completion — transient
errors don't mark nodes as "seen."

Schema: AgentVisit{nodeUuid, nodeKey, agent, timestamp, outcome}
Storage: append_visits(), replay_visits(), in-memory VisitIndex
Recording: daemon records visits after successful LLM call
API: agent_prompt() returns AgentBatch{prompt, node_keys} so callers
know which nodes to mark as visited.

Groundwork for using visit recency in agent node selection — agents
will deprioritize recently-visited nodes.

poc-memory/src/agents/consolidate.rs

@@ -98,8 +98,8 @@ pub fn consolidate_full_with_progress(
             *store = Store::load()?;
         }
 
-        let prompt = match super::prompts::agent_prompt(store, agent_type, *count) {
-            Ok(p) => p,
+        let agent_batch = match super::prompts::agent_prompt(store, agent_type, *count) {
+            Ok(b) => b,
             Err(e) => {
                 let msg = format!("  ERROR building prompt: {}", e);
                 log_line(&mut log_buf, &msg);
@@ -109,10 +109,10 @@ pub fn consolidate_full_with_progress(
             }
         };
 
-        log_line(&mut log_buf, &format!("  Prompt: {} chars (~{} tokens)",
-            prompt.len(), prompt.len() / 4));
+        log_line(&mut log_buf, &format!("  Prompt: {} chars (~{} tokens), {} nodes",
+            agent_batch.prompt.len(), agent_batch.prompt.len() / 4, agent_batch.node_keys.len()));
 
-        let response = match call_sonnet("consolidate", &prompt) {
+        let response = match call_sonnet("consolidate", &agent_batch.prompt) {
             Ok(r) => r,
             Err(e) => {
                 let msg = format!("  ERROR from Sonnet: {}", e);
@@ -131,6 +131,13 @@ pub fn consolidate_full_with_progress(
             store::Provenance::AgentConsolidate).ok();
         reports.push(report_key.clone());
 
+        // Record visits for successfully processed nodes
+        if !agent_batch.node_keys.is_empty() {
+            if let Err(e) = store.record_agent_visits(&agent_batch.node_keys, agent_type) {
+                log_line(&mut log_buf, &format!("  Visit recording: {}", e));
+            }
+        }
+
         let msg = format!("  Done: {} lines → {}", response.lines().count(), report_key);
         log_line(&mut log_buf, &msg);
         on_progress(&msg);

poc-memory/src/agents/daemon.rs

@@ -137,10 +137,11 @@ fn job_consolidation_agent(
         };
         ctx.log_line(&format!("building prompt: {}", label));
 
-        let prompt = super::prompts::agent_prompt(&store, &agent, batch)?;
-        ctx.log_line(&format!("prompt: {} chars, calling Sonnet", prompt.len()));
+        let agent_batch = super::prompts::agent_prompt(&store, &agent, batch)?;
+        ctx.log_line(&format!("prompt: {} chars ({} nodes), calling Sonnet",
+            agent_batch.prompt.len(), agent_batch.node_keys.len()));
 
-        let response = super::llm::call_sonnet("consolidate", &prompt)?;
+        let response = super::llm::call_sonnet("consolidate", &agent_batch.prompt)?;
 
         let ts = crate::store::format_datetime(crate::store::now_epoch())
             .replace([':', '-', 'T'], "");
@@ -148,6 +149,13 @@ fn job_consolidation_agent(
         store.upsert_provenance(&report_key, &response,
             crate::store::Provenance::AgentConsolidate).ok();
 
+        // Record visits for successfully processed nodes
+        if !agent_batch.node_keys.is_empty() {
+            if let Err(e) = store.record_agent_visits(&agent_batch.node_keys, &agent) {
+                ctx.log_line(&format!("visit recording: {}", e));
+            }
+        }
+
         ctx.log_line(&format!("done: {} lines → {}", response.lines().count(), report_key));
         Ok(())
     })
@@ -165,14 +173,16 @@ fn job_rename_agent(
         let batch = if batch_size == 0 { 10 } else { batch_size };
         ctx.log_line(&format!("building prompt: rename (batch={})", batch));
 
-        let prompt = super::prompts::agent_prompt(&store, "rename", batch)?;
-        ctx.log_line(&format!("prompt: {} chars, calling Sonnet", prompt.len()));
+        let agent_batch = super::prompts::agent_prompt(&store, "rename", batch)?;
+        ctx.log_line(&format!("prompt: {} chars ({} nodes), calling Sonnet",
+            agent_batch.prompt.len(), agent_batch.node_keys.len()));
 
-        let response = super::llm::call_sonnet("consolidate", &prompt)?;
+        let response = super::llm::call_sonnet("consolidate", &agent_batch.prompt)?;
 
         // Parse RENAME actions directly from response
         let mut applied = 0;
         let mut skipped = 0;
+        let mut successfully_renamed: Vec<String> = Vec::new();
         for line in response.lines() {
             let trimmed = line.trim();
             if !trimmed.starts_with("RENAME ") { continue; }
@@ -208,6 +218,7 @@ fn job_rename_agent(
             match store.rename_node(&resolved, new_key) {
                 Ok(()) => {
                     ctx.log_line(&format!("renamed: {} → {}", resolved, new_key));
+                    successfully_renamed.push(new_key.to_string());
                     applied += 1;
                 }
                 Err(e) => {
@@ -221,6 +232,13 @@ fn job_rename_agent(
             store.save()?;
         }
 
+        // Record visits for successfully renamed nodes
+        if !successfully_renamed.is_empty() {
+            if let Err(e) = store.record_agent_visits(&successfully_renamed, "rename") {
+                ctx.log_line(&format!("visit recording: {}", e));
+            }
+        }
+
         // Also store the report for auditing
         let ts = crate::store::format_datetime(crate::store::now_epoch())
             .replace([':', '-', 'T'], "");

poc-memory/src/agents/prompts.rs

@@ -11,6 +11,14 @@ use crate::neuro::{
     replay_queue, replay_queue_with_graph, detect_interference,
 };
 
+/// Result of building an agent prompt — includes both the prompt text
+/// and the keys of nodes selected for processing, so the caller can
+/// record visits after successful completion.
+pub struct AgentBatch {
+    pub prompt: String,
+    pub node_keys: Vec<String>,
+}
+
 /// Load a prompt template, replacing {{PLACEHOLDER}} with data
 pub fn load_prompt(name: &str, replacements: &[(&str, &str)]) -> Result<String, String> {
     let path = crate::config::get().prompts_dir.join(format!("{}.md", name));
@@ -260,28 +268,23 @@ fn format_pairs_section(
     out
 }
 
-/// Format rename candidates: nodes with auto-generated or opaque keys
-fn format_rename_candidates(store: &Store, count: usize) -> String {
+/// Format rename candidates, returning both keys and formatted section
+fn format_rename_candidates_with_keys(store: &Store, count: usize) -> (Vec<String>, String) {
     let mut candidates: Vec<(&str, &crate::store::Node)> = store.nodes.iter()
         .filter(|(key, _)| {
-            // Only rename nodes with long auto-generated keys
             if key.len() < 60 { return false; }
-
-            // Journal entries with auto-slugs
             if key.starts_with("journal#j-") { return true; }
-
-            // Mined transcripts with UUIDs
             if key.starts_with("_mined-transcripts#f-") { return true; }
-
             false
         })
         .map(|(k, n)| (k.as_str(), n))
         .collect();
 
-    // Sort by timestamp (newest first) so we rename recent stuff first
     candidates.sort_by(|a, b| b.1.timestamp.cmp(&a.1.timestamp));
     candidates.truncate(count);
 
+    let keys: Vec<String> = candidates.iter().map(|(k, _)| k.to_string()).collect();
+
     let mut out = String::new();
     out.push_str(&format!("## Nodes to rename ({} of {} candidates)\n\n",
         candidates.len(),
@@ -308,7 +311,7 @@ fn format_rename_candidates(store: &Store, count: usize) -> String {
 
         out.push_str("---\n\n");
     }
-    out
+    (keys, out)
 }
 
 /// Get split candidates sorted by size (largest first)
@@ -437,8 +440,10 @@ pub fn consolidation_batch(store: &Store, count: usize, auto: bool) -> Result<()
     Ok(())
 }
 
-/// Generate a specific agent prompt with filled-in data
-pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<String, String> {
+/// Generate a specific agent prompt with filled-in data.
+/// Returns an AgentBatch with the prompt text and the keys of nodes
+/// selected for processing (for visit tracking on success).
+pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<AgentBatch, String> {
     let graph = store.build_graph();
     let topology = format_topology_header(&graph);
 
@@ -447,8 +452,10 @@ pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<String,
     match agent {
         "replay" => {
             let items = replay_queue_with_graph(store, count, &graph, emb.as_ref());
+            let keys: Vec<String> = items.iter().map(|i| i.key.clone()).collect();
             let nodes_section = format_nodes_section(store, &items, &graph);
-            load_prompt("replay", &[("{{TOPOLOGY}}", &topology), ("{{NODES}}", &nodes_section)])
+            let prompt = load_prompt("replay", &[("{{TOPOLOGY}}", &topology), ("{{NODES}}", &nodes_section)])?;
+            Ok(AgentBatch { prompt, node_keys: keys })
         }
         "linker" => {
             // Filter to episodic entries
@@ -459,14 +466,21 @@ pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<String,
                     .unwrap_or(false)
             });
             items.truncate(count);
+            let keys: Vec<String> = items.iter().map(|i| i.key.clone()).collect();
             let nodes_section = format_nodes_section(store, &items, &graph);
-            load_prompt("linker", &[("{{TOPOLOGY}}", &topology), ("{{NODES}}", &nodes_section)])
+            let prompt = load_prompt("linker", &[("{{TOPOLOGY}}", &topology), ("{{NODES}}", &nodes_section)])?;
+            Ok(AgentBatch { prompt, node_keys: keys })
         }
         "separator" => {
             let mut pairs = detect_interference(store, &graph, 0.5);
             pairs.truncate(count);
+            // Both nodes in each pair count as visited
+            let keys: Vec<String> = pairs.iter()
+                .flat_map(|(a, b, _)| vec![a.clone(), b.clone()])
+                .collect();
             let pairs_section = format_pairs_section(&pairs, store, &graph);
-            load_prompt("separator", &[("{{TOPOLOGY}}", &topology), ("{{PAIRS}}", &pairs_section)])
+            let prompt = load_prompt("separator", &[("{{TOPOLOGY}}", &topology), ("{{PAIRS}}", &pairs_section)])?;
+            Ok(AgentBatch { prompt, node_keys: keys })
         }
         "transfer" => {
             // Recent episodic entries
@@ -493,15 +507,19 @@ pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<String,
                 })
                 .collect();
             let episodes_section = format_nodes_section(store, &items, &graph);
-            load_prompt("transfer", &[("{{TOPOLOGY}}", &topology), ("{{EPISODES}}", &episodes_section)])
+            let prompt = load_prompt("transfer", &[("{{TOPOLOGY}}", &topology), ("{{EPISODES}}", &episodes_section)])?;
+            Ok(AgentBatch { prompt, node_keys: episode_keys })
         }
         "health" => {
+            // Health agent analyzes the whole graph, no specific nodes
             let health_section = format_health_section(store, &graph);
-            load_prompt("health", &[("{{TOPOLOGY}}", &topology), ("{{HEALTH}}", &health_section)])
+            let prompt = load_prompt("health", &[("{{TOPOLOGY}}", &topology), ("{{HEALTH}}", &health_section)])?;
+            Ok(AgentBatch { prompt, node_keys: vec![] })
         }
         "rename" => {
-            let nodes_section = format_rename_candidates(store, count);
-            load_prompt("rename", &[("{{NODES}}", &nodes_section)])
+            let (keys, nodes_section) = format_rename_candidates_with_keys(store, count);
+            let prompt = load_prompt("rename", &[("{{NODES}}", &nodes_section)])?;
+            Ok(AgentBatch { prompt, node_keys: keys })
         }
         "split" => {
             // Phase 1: plan prompt for the largest candidate
@@ -509,9 +527,10 @@ pub fn agent_prompt(store: &Store, agent: &str, count: usize) -> Result<String,
             if candidates.is_empty() {
                 return Err("No nodes large enough to split".to_string());
             }
-            let key = &candidates[0];
-            let node_section = format_split_plan_node(store, &graph, key);
-            load_prompt("split-plan", &[("{{TOPOLOGY}}", &topology), ("{{NODE}}", &node_section)])
+            let key = candidates[0].clone();
+            let node_section = format_split_plan_node(store, &graph, &key);
+            let prompt = load_prompt("split-plan", &[("{{TOPOLOGY}}", &topology), ("{{NODE}}", &node_section)])?;
+            Ok(AgentBatch { prompt, node_keys: vec![key] })
         }
         _ => Err(format!("Unknown agent: {}. Use: replay, linker, separator, transfer, health, rename, split", agent)),
     }

poc-memory/src/store/persist.rs

@@ -29,7 +29,14 @@ impl Store {
     pub fn load() -> Result<Store, String> {
         // 1. Try rkyv mmap snapshot (~4ms with deserialize, <1ms zero-copy)
         match Self::load_snapshot_mmap() {
-            Ok(Some(store)) => return Ok(store),
+            Ok(Some(mut store)) => {
+                // rkyv snapshot doesn't include visits — replay from log
+                let visits_p = visits_path();
+                if visits_p.exists() {
+                    store.replay_visits(&visits_p).ok();
+                }
+                return Ok(store);
+            },
             Ok(None) => {},
             Err(e) => eprintln!("rkyv snapshot: {}", e),
         }
@@ -76,6 +83,10 @@ impl Store {
         if rels_p.exists() {
             store.replay_relations(&rels_p)?;
         }
+        let visits_p = visits_path();
+        if visits_p.exists() {
+            store.replay_visits(&visits_p)?;
+        }
 
         // Record log sizes after replay — this is the state we reflect
         store.loaded_nodes_size = fs::metadata(&nodes_p).map(|m| m.len()).unwrap_or(0);
@@ -318,6 +329,100 @@ impl Store {
         Ok(())
     }
 
+    /// Append agent visit records to the visits log.
+    pub fn append_visits(&mut self, visits: &[AgentVisit]) -> Result<(), String> {
+        if visits.is_empty() { return Ok(()); }
+
+        let mut msg = message::Builder::new_default();
+        {
+            let log = msg.init_root::<memory_capnp::agent_visit_log::Builder>();
+            let mut list = log.init_visits(visits.len() as u32);
+            for (i, visit) in visits.iter().enumerate() {
+                visit.to_capnp(list.reborrow().get(i as u32));
+            }
+        }
+        let mut buf = Vec::new();
+        serialize::write_message(&mut buf, &msg)
+            .map_err(|e| format!("serialize visits: {}", e))?;
+
+        let path = visits_path();
+        let file = fs::OpenOptions::new()
+            .create(true).append(true).open(&path)
+            .map_err(|e| format!("open {}: {}", path.display(), e))?;
+        use std::io::Write;
+        (&file).write_all(&buf)
+            .map_err(|e| format!("write visits: {}", e))?;
+
+        // Update in-memory index
+        for v in visits {
+            self.visits
+                .entry(v.node_key.clone())
+                .or_default()
+                .insert(v.agent.clone(), v.timestamp);
+        }
+
+        Ok(())
+    }
+
+    /// Replay visits log to rebuild in-memory index.
+    fn replay_visits(&mut self, path: &Path) -> Result<(), String> {
+        let file = fs::File::open(path)
+            .map_err(|e| format!("open {}: {}", path.display(), e))?;
+        let mut reader = BufReader::new(file);
+
+        while reader.stream_position().map_err(|e| e.to_string())?
+              < fs::metadata(path).map_err(|e| e.to_string())?.len()
+        {
+            let msg = match serialize::read_message(&mut reader, Default::default()) {
+                Ok(m) => m,
+                Err(_) => break,
+            };
+            let log = msg.get_root::<memory_capnp::agent_visit_log::Reader>()
+                .map_err(|e| format!("read visit log: {}", e))?;
+
+            for visit in log.get_visits().map_err(|e| e.to_string())? {
+                let key = visit.get_node_key().ok()
+                    .and_then(|t| t.to_str().ok())
+                    .unwrap_or("")
+                    .to_string();
+                let agent = visit.get_agent().ok()
+                    .and_then(|t| t.to_str().ok())
+                    .unwrap_or("")
+                    .to_string();
+                let ts = visit.get_timestamp();
+
+                if !key.is_empty() && !agent.is_empty() {
+                    let entry = self.visits.entry(key).or_default();
+                    // Keep latest timestamp per agent
+                    let existing = entry.entry(agent).or_insert(0);
+                    if ts > *existing {
+                        *existing = ts;
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    /// Record visits for a batch of node keys from a successful agent run.
+    pub fn record_agent_visits(&mut self, node_keys: &[String], agent: &str) -> Result<(), String> {
+        let visits: Vec<AgentVisit> = node_keys.iter()
+            .filter_map(|key| {
+                let node = self.nodes.get(key)?;
+                Some(new_visit(node.uuid, key, agent, "processed"))
+            })
+            .collect();
+        self.append_visits(&visits)
+    }
+
+    /// Get the last time an agent visited a node. Returns 0 if never visited.
+    pub fn last_visited(&self, node_key: &str, agent: &str) -> i64 {
+        self.visits.get(node_key)
+            .and_then(|agents| agents.get(agent))
+            .copied()
+            .unwrap_or(0)
+    }
+
     /// Save the derived cache with log size header for staleness detection.
     /// Uses atomic write (tmp + rename) to prevent partial reads.
     pub fn save(&self) -> Result<(), String> {

poc-memory/src/store/types.rs

@@ -394,6 +394,9 @@ pub struct GapRecord {
     pub timestamp: String,
 }
 
+/// Per-node agent visit index: node_key → (agent_type → last_visit_timestamp)
+pub type VisitIndex = HashMap<String, HashMap<String, i64>>;
+
 // The full in-memory store
 #[derive(Default, Serialize, Deserialize)]
 pub struct Store {
@@ -404,6 +407,9 @@ pub struct Store {
     pub retrieval_log: Vec<RetrievalEvent>,
     pub gaps: Vec<GapRecord>,
     pub params: Params,
+    /// Agent visit tracking: node_key → (agent_type → last_visit_epoch)
+    #[serde(default)]
+    pub visits: VisitIndex,
     /// Log sizes at load time — used by save() to write correct staleness header.
     /// If another writer appended since we loaded, our cache will be marked stale
     /// (recorded size < actual size), forcing the next reader to replay the log.
@@ -490,6 +496,38 @@ pub fn new_node(key: &str, content: &str) -> Node {
     }
 }
 
+/// Agent visit record — tracks when an agent successfully processed a node
+#[derive(Clone, Debug, Serialize, Deserialize)]
+pub struct AgentVisit {
+    pub node_uuid: [u8; 16],
+    pub node_key: String,
+    pub agent: String,
+    pub timestamp: i64,
+    pub outcome: String,
+}
+
+capnp_message!(AgentVisit,
+    reader: memory_capnp::agent_visit::Reader<'_>,
+    builder: memory_capnp::agent_visit::Builder<'_>,
+    text: [node_key, agent, outcome],
+    uuid: [node_uuid],
+    prim: [timestamp],
+    enm:  [],
+    skip: [],
+);
+
+pub fn new_visit(node_uuid: [u8; 16], node_key: &str, agent: &str, outcome: &str) -> AgentVisit {
+    AgentVisit {
+        node_uuid,
+        node_key: node_key.to_string(),
+        agent: agent.to_string(),
+        timestamp: now_epoch(),
+        outcome: outcome.to_string(),
+    }
+}
+
+pub(crate) fn visits_path() -> PathBuf { memory_dir().join("visits.capnp") }
+
 /// Create a new relation
 pub fn new_relation(
     source_uuid: [u8; 16],