memory-search: add --query mode and prompt key boost

Two changes:

1. New -q/--query flag for direct search without hook machinery.
   Useful for debugging: memory-search -q inner-life-sexuality-intimacy
   shows seeds, spread results, and rankings.

2. Prompt key boost: when the current prompt contains a node key
   (>=5 chars) as a substring, boost that term by +10.0. This ensures
   explicit mentions fire as strong seeds for spread, while the graph
   still determines what gets pulled in.

Co-Authored-By: ProofOfConcept <poc@bcachefs.org>

poc-memory/src/agents/knowledge.rs

@@ -9,8 +9,8 @@
 //   - Conversation fragment selection (for observation agent)
 
 use crate::graph::Graph;
-use super::llm;
 use crate::spectral;
+use super::llm;
 use crate::store::{self, Store, new_relation, RelationType};
 
 use regex::Regex;
@@ -940,14 +940,21 @@ fn run_cycle(
 
     depth_db.save(&mut store);
 
-    // Recompute spectral if anything changed
+    // Recompute spectral at most once per hour — O(n³) is expensive at 14k+ nodes
     if total_applied > 0 {
-        eprintln!("\n  Recomputing spectral embedding...");
+        let stale = spectral::embedding_path()
+            .metadata()
+            .and_then(|m| m.modified())
+            .map(|t| t.elapsed().unwrap_or_default() > std::time::Duration::from_secs(3600))
+            .unwrap_or(true);
+        if stale {
+            eprintln!("\n  Recomputing spectral embedding (>1h stale)...");
             let graph = store.build_graph();
             let result = spectral::decompose(&graph, 8);
             let emb = spectral::to_embedding(&result);
             spectral::save_embedding(&emb).ok();
         }
+    }
 
     let graph = store.build_graph();
     let metrics_after = GraphMetrics::from_graph(&store, &graph);

poc-memory/src/bin/memory-search.rs

@@ -39,6 +39,10 @@ struct Args {
     #[arg(long, default_value = "5")]
     max_results: usize,
 
+    /// Search query (bypasses stashed input, uses this as the prompt)
+    #[arg(long, short)]
+    query: Option<String>,
+
     /// Algorithm pipeline stages: e.g. spread spectral,k=20 spread,max_hops=4
     /// Default: spread.
     pipeline: Vec<String>,
@@ -61,6 +65,12 @@ fn main() {
         return;
     }
 
+    // --query mode: skip all hook/context machinery, just search
+    if let Some(ref query_str) = args.query {
+        run_query_mode(query_str, &args);
+        return;
+    }
+
     let input = if args.hook {
         // Hook mode: read from stdin, stash for later debug runs
         let mut buf = String::new();
@@ -206,6 +216,22 @@ fn main() {
         }
     }
 
+    // Boost node keys that appear as substrings in the current prompt.
+    // Makes explicit mentions strong seeds for spread — the graph
+    // determines what gets pulled in, this just ensures the seed fires.
+    {
+        let prompt_lower = prompt.to_lowercase();
+        for (key, node) in &store.nodes {
+            if node.deleted { continue; }
+            let key_lower = key.to_lowercase();
+            if key_lower.len() < 5 { continue; }
+            if prompt_lower.contains(&key_lower) {
+                *terms.entry(key_lower).or_insert(0.0) += 10.0;
+                if debug { println!("[memory-search] prompt key boost: {} (+10.0)", key); }
+            }
+        }
+    }
+
     if debug {
         println!("[memory-search] {} terms total", terms.len());
         let mut by_weight: Vec<_> = terms.iter().collect();
@@ -336,6 +362,65 @@ fn main() {
     cleanup_stale_files(&state_dir, Duration::from_secs(86400));
 }
 
+/// Direct query mode: search for a term without hook/stash machinery.
+fn run_query_mode(query: &str, args: &Args) {
+    let store = match poc_memory::store::Store::load() {
+        Ok(s) => s,
+        Err(e) => { eprintln!("failed to load store: {}", e); return; }
+    };
+
+    // Build terms from the query string
+    let mut terms: BTreeMap<String, f64> = BTreeMap::new();
+    let prompt_terms = search::extract_query_terms(query, 8);
+    for word in prompt_terms.split_whitespace() {
+        terms.entry(word.to_lowercase()).or_insert(1.0);
+    }
+
+    // Also check for exact node key match (the query itself, lowercased)
+    let query_lower = query.to_lowercase();
+    for (key, node) in &store.nodes {
+        if node.deleted { continue; }
+        if key.to_lowercase() == query_lower {
+            terms.insert(query_lower.clone(), 10.0);
+            break;
+        }
+    }
+
+    println!("[query] terms: {:?}", terms);
+
+    if terms.is_empty() {
+        println!("[query] no terms extracted");
+        return;
+    }
+
+    let graph = poc_memory::graph::build_graph_fast(&store);
+    let (seeds, direct_hits) = search::match_seeds(&terms, &store);
+
+    println!("[query] {} seeds", seeds.len());
+    let mut sorted = seeds.clone();
+    sorted.sort_by(|a, b| b.1.total_cmp(&a.1));
+    for (key, score) in sorted.iter().take(20) {
+        let marker = if direct_hits.contains(key) { "→" } else { " " };
+        println!("  {} {:.4}  {}", marker, score, key);
+    }
+
+    let pipeline: Vec<AlgoStage> = if args.pipeline.is_empty() {
+        vec![AlgoStage::parse("spread").unwrap()]
+    } else {
+        args.pipeline.iter()
+            .filter_map(|a| AlgoStage::parse(a).ok())
+            .collect()
+    };
+
+    let max_results = args.max_results.max(25);
+    let results = search::run_pipeline(&pipeline, seeds, &graph, &store, true, max_results);
+
+    println!("\n[query] top {} results:", results.len().min(25));
+    for (i, (key, score)) in results.iter().take(25).enumerate() {
+        let marker = if direct_hits.contains(key) { "→" } else { " " };
+        println!("  {:2}. {} [{:.4}] {}", i + 1, marker, score, key);
+    }
+}
 
 /// Split context output into chunks of approximately `max_bytes`, breaking
 /// at section boundaries ("--- KEY (group) ---" lines).

poc-memory/src/spectral.rs

@@ -42,7 +42,7 @@ pub struct SpectralEmbedding {
     pub coords: HashMap<String, Vec<f64>>,
 }
 
-fn embedding_path() -> PathBuf {
+pub fn embedding_path() -> PathBuf {
     crate::store::memory_dir().join("spectral-embedding.json")
 }