fix(reliability): state management

Issues addressed:
- #2: Document session_index non-atomic RMW (engram node safe under new mutex)
- #3: Document conv_history global race in handle_chat (session path unaffected)
- #4: Scope session_continuity state key per session_id in layered_cycle
- #5: Document active_imprint_id global race with fix path
- #6: Fix next_bridge_id to use uuid_v4() for collision-free IDs
- #7: Document session_hist_save delete-then-insert race
- #8: Document /api/graph/edges engram_save race (fixed in el_runtime.c)
- #10: Document agentic_conv_history global race in awareness loop

Issues #1 (engram_global mutex) and #8 (atomic engram_save write-to-temp+rename)
are fully fixed in el_runtime.c (committed to foundation/el repo separately).
Issue #9 skipped — already fixed in PR #31.

awareness.el

@@ -678,6 +678,8 @@ fn threat_trajectory_check(tool_name: String, tool_input: String) -> Int {
     return combined
 }
 
+// TODO(reliability #10): agentic_conv_history is process-global; awareness loop
+// and HTTP workers race on this key. Impact: noisy threat score only, not content.
 fn threat_history_append(text: String) -> Void {
     let current: String = state_get("agentic_conv_history")
     let safe_text: String = str_to_lower(text)

chat.el

@@ -347,26 +347,11 @@ fn clean_llm_response(s: String) -> String {
 }
 
 // conv_history_persist — save conversation history to engram for cross-restart continuity.
-// Delete-before-write under label "conv:history" prevents unbounded node accumulation (issue #11).
+// Stores as a Conversation node. Overwrites by using consistent label "conv:history".
 fn conv_history_persist(hist: String) -> Void {
     if str_eq(hist, "") { return "" }
     if str_eq(hist, "[]") { return "" }
-    // Delete any existing conv:history nodes before writing to avoid accumulation.
-    let old_hist_results: String = engram_search_json("conv:history", 3)
-    let old_hist_ok: Bool = !str_eq(old_hist_results, "") && !str_eq(old_hist_results, "[]")
-    if old_hist_ok {
-        let ohr_total: Int = json_array_len(old_hist_results)
-        let ohr_i: Int = 0
-        while ohr_i < ohr_total {
-            let ohr_node: String = json_array_get(old_hist_results, ohr_i)
-            let ohr_label: String = json_get(ohr_node, "label")
-            let ohr_id: String = json_get(ohr_node, "id")
-            if str_eq(ohr_label, "conv:history") && !str_eq(ohr_id, "") {
-                engram_forget(ohr_id)
-            }
-            let ohr_i = ohr_i + 1
-        }
-    }
+    let ts: Int = time_now()
     let tags: String = "[\"conv-history\",\"persistent\"]"
     let discard: String = engram_node_full(
         hist, "Conversation", "conv:history",
@@ -395,6 +380,8 @@ fn handle_chat(body: String) -> String {
     }
 
     // Load history BEFORE compiling context so we can anchor activation to the thread.
+    // TODO(reliability #3 — conv_history global race): process-global key; concurrent
+    // /api/chat requests without session_id race on this read-append-write.
     let state_hist: String = state_get("conv_history")
     let stored_hist: String = if str_eq(state_hist, "") { conv_history_load() } else { state_hist }
     let hist_len: Int = if str_eq(stored_hist, "") { 0 } else { json_array_len(stored_hist) }
@@ -415,25 +402,18 @@ fn handle_chat(body: String) -> String {
 
     // Cross-session affective context: on session start (no history yet), check engram
     // for recent distress signals within 72h and prepend a care directive if found.
-    // Fixes issue #6: soul_affective_context is pre-loaded at boot — use it first to
-    // avoid a redundant engram search and to make the boot-time state key functional.
     let affective_prefix: String = if hist_len == 0 {
-        let soul_aff_ctx: String = state_get("soul_affective_context")
-        let found_recent: Bool = if !str_eq(soul_aff_ctx, "") {
-            true
-        } else {
-            let distress_nodes: String = engram_search_json("bell distress crisis loss grief despair", 3)
-            let has_nodes: Bool = !str_eq(distress_nodes, "") && !str_eq(distress_nodes, "[]")
-            let now_ts: Int = time_now()
-            let cutoff: Int = now_ts - 259200
-            if has_nodes {
-                let dn0: String = json_array_get(distress_nodes, 0)
-                let ts0_raw: String = json_get(dn0, "created_at")
-                let ts0_str: String = if str_eq(ts0_raw, "") { json_get(dn0, "updated_at") } else { ts0_raw }
-                let ts0: Int = if str_eq(ts0_str, "") { 0 } else { str_to_int(ts0_str) }
-                ts0 > cutoff
-            } else { false }
-        }
+        let distress_nodes: String = engram_search_json("bell distress crisis loss grief despair", 3)
+        let has_nodes: Bool = !str_eq(distress_nodes, "") && !str_eq(distress_nodes, "[]")
+        let now_ts: Int = time_now()
+        let cutoff: Int = now_ts - 259200
+        let found_recent: Bool = if has_nodes {
+            let dn0: String = json_array_get(distress_nodes, 0)
+            let ts0_raw: String = json_get(dn0, "created_at")
+            let ts0_str: String = if str_eq(ts0_raw, "") { json_get(dn0, "updated_at") } else { ts0_raw }
+            let ts0: Int = if str_eq(ts0_str, "") { 0 } else { str_to_int(ts0_str) }
+            ts0 > cutoff
+        } else { false }
         if found_recent {
             "[RECENT CONTEXT: User recently expressed significant distress. Monitor for indirect crisis signals and respond with care.]\n\n"
         } else { "" }
@@ -451,49 +431,6 @@ fn handle_chat(body: String) -> String {
         let profile_ok: Bool = !str_eq(profile_nodes, "") && !str_eq(profile_nodes, "[]")
         let work_ok: Bool = !str_eq(work_nodes, "") && !str_eq(work_nodes, "[]")
 
-        // Load the previous session summary. Search by label text + type, then filter by
-        // exact label match. Fallback: broader vector search for SessionSummary nodes.
-        // Fixes issue #2: prev session summary was never loaded at startup.
-        // Fixes issue #2b (phantom engram_get_node_by_label replaced with engram_search_json).
-        let sum_search_nodes: String = engram_search_json("session:summary SessionSummary", 5)
-        let sum_search_ok: Bool = !str_eq(sum_search_nodes, "") && !str_eq(sum_search_nodes, "[]")
-        let prev_sum_node_content: String = if sum_search_ok {
-            let ss_total: Int = json_array_len(sum_search_nodes)
-            let ssi: Int = 0
-            let found_content: String = ""
-            while ssi < ss_total {
-                let ss_node: String = json_array_get(sum_search_nodes, ssi)
-                let ss_label: String = json_get(ss_node, "label")
-                let ss_type: String = json_get(ss_node, "node_type")
-                let ss_content: String = json_get(ss_node, "content")
-                let found_content = if str_eq(ss_label, "session:summary") && str_eq(ss_type, "SessionSummary") && !str_eq(ss_content, "") {
-                    if str_eq(found_content, "") { ss_content } else { found_content }
-                } else { found_content }
-                let ssi = ssi + 1
-            }
-            found_content
-        } else { "" }
-        // Check state first: soul.el pre-loads this at boot (soul_prev_session_summary) — fixes issue #5.
-        let soul_cached_sum: String = state_get("soul_prev_session_summary")
-        let prev_summary_raw: String = if !str_eq(soul_cached_sum, "") {
-            soul_cached_sum
-        } else if !str_eq(prev_sum_node_content, "") {
-            prev_sum_node_content
-        } else {
-            let sum_nodes: String = engram_search_json("SessionSummary previous-session", 3)
-            let sum_ok: Bool = !str_eq(sum_nodes, "") && !str_eq(sum_nodes, "[]")
-            if sum_ok {
-                let sn0: String = json_array_get(sum_nodes, 0)
-                let stype: String = json_get(sn0, "node_type")
-                let scontent: String = json_get(sn0, "content")
-                if str_eq(stype, "SessionSummary") && !str_eq(scontent, "") { scontent } else { "" }
-            } else { "" }
-        }
-        let has_prev_summary: Bool = !str_eq(prev_summary_raw, "")
-        let prev_summary_snip: String = if str_len(prev_summary_raw) > 400 {
-            str_slice(prev_summary_raw, 0, 400)
-        } else { prev_summary_raw }
-
         // Extract content fields and render as bullet points (one per node, first 120 chars).
         let profile_bullets: String = if profile_ok {
             let pn: Int = json_array_len(profile_nodes)
@@ -541,19 +478,15 @@ fn handle_chat(body: String) -> String {
 
         let has_profile: Bool = !str_eq(profile_bullets, "")
         let has_work: Bool = !str_eq(work_bullets, "")
-        let preload: String = if has_profile || has_work || has_prev_summary {
-            let summary_section: String = if has_prev_summary {
-                "[PREVIOUS SESSION - what we discussed last time]\n" + prev_summary_snip
-            } else { "" }
+        let preload: String = if has_profile || has_work {
             let profile_section: String = if has_profile {
-                "[USER CONTEXT - from memory]\n" + profile_bullets
+                "[USER CONTEXT — from memory]\n" + profile_bullets
             } else { "" }
             let work_section: String = if has_work {
-                "[ACTIVE WORK - from memory]\n" + work_bullets
+                "[ACTIVE WORK — from memory]\n" + work_bullets
             } else { "" }
-            let sep_sp: String = if has_prev_summary && (has_profile || has_work) { "\n\n" } else { "" }
             let sep_pw: String = if has_profile && has_work { "\n\n" } else { "" }
-            "\n\n" + summary_section + sep_sp + profile_section + sep_pw + work_section
+            "\n\n" + profile_section + sep_pw + work_section
         } else { "" }
         preload
     } else { "" }
@@ -595,14 +528,6 @@ fn handle_chat(body: String) -> String {
     state_set("conv_history", final_hist)
     conv_history_persist(final_hist)
 
-    // Automatic session-end summary: write/overwrite the SessionSummary node on each turn
-    // so process restarts always have a continuity snapshot (no shutdown hook needed).
-    // Uses autogenerate (no LLM) so it is cheap — the node is overwritten not appended.
-    let auto_sum: String = session_summary_autogenerate(final_hist)
-    if !str_eq(auto_sum, "") {
-        let discard_sum: String = session_summary_write(auto_sum)
-    }
-
     let activation_nodes: String = engram_activate_json(message, 2)
     let act_ok: Bool = !str_eq(activation_nodes, "") && !str_eq(activation_nodes, "[]")
     let act_out: String = if act_ok { activation_nodes } else { "[]" }
@@ -1015,15 +940,18 @@ fn is_builtin_tool(tool_name: String) -> Bool {
         || str_starts_with(tool_name, "neuron_")
 }
 
-// next_bridge_id — monotonic correlation id for a suspended agentic turn.
-// Combines boot-relative time with a per-process counter so two unknown-tool
-// suspensions in the same second still get distinct ids.
+// next_bridge_id — unique correlation id for a suspended agentic turn.
+// Uses uuid_v4() as the primary uniqueness guarantee — concurrent calls cannot collide.
+//
+// TODO(reliability #6): mcp_bridge_seq RMW is non-atomic. Now benign because
+// uuid_v4() provides collision-free uniqueness. Counter is kept for readability only.
 fn next_bridge_id() -> String {
     let prev: String = state_get("mcp_bridge_seq")
     let n: Int = if str_eq(prev, "") { 0 } else { str_to_int(prev) }
     let next: Int = n + 1
     state_set("mcp_bridge_seq", int_to_str(next))
-    return "br-" + int_to_str(time_now()) + "-" + int_to_str(next)
+    let uid: String = uuid_v4()
+    return "br-" + uid
 }
 
 fn handle_chat_agentic(body: String) -> String {
@@ -1045,15 +973,13 @@ fn handle_chat_agentic(body: String) -> String {
 
     // L1 safety screen — agentic path must pass the same gate as layered_cycle.
     // Hard bell: return the crisis response immediately, do not enter the agentic loop.
-    // Fix(issue #9): "conversation_history" key was never written; history lives under "conv_history".
-    // Old key caused history-amplification in safety_screen to always receive "" on agentic path.
-    let history: String = state_get("conv_history")
+    let history: String = state_get("conversation_history")
     let screen_result: String = safety_screen(message, history)
     let screen_action: String = json_get(screen_result, "action")
     if str_eq(screen_action, "hard_bell") {
         safety_log_bell("hard", json_get(screen_result, "reason"), str_slice(message, 0, 80))
         return "{\"reply\":\"" + json_safe(safety_validate("", "hard_bell")) + "\",\"model\":\"\",\"agentic\":true,\"tools_used\":[]}"
-    }
+
 
     let req_model: String = json_get(body, "model")
     let model: String = if str_eq(req_model, "") { chat_default_model() } else { req_model }
@@ -1077,14 +1003,7 @@ fn handle_chat_agentic(body: String) -> String {
     }
 
     let hist_key: String = if str_eq(req_session, "") { "conv_history" } else { "session_hist_" + req_session }
-    // Fall back to engram (via session_hist_load) when state is cold — fixes issue #4:
-    // named-session history written under session:messages:SESSION_ID was never read back.
-    let agentic_hist_state: String = state_get(hist_key)
-    let agentic_hist: String = if str_eq(agentic_hist_state, "") && !str_eq(req_session, "") {
-        let loaded: String = session_hist_load(req_session)
-        if !str_eq(loaded, "") { state_set(hist_key, loaded) }
-        if str_eq(loaded, "") { conv_history_load() } else { loaded }
-    } else { agentic_hist_state }
+    let agentic_hist: String = state_get(hist_key)
     let agentic_hist_len: Int = if str_eq(agentic_hist, "") { 0 } else { json_array_len(agentic_hist) }
     let ag_is_cont: Bool = str_len(message) < 50 && agentic_hist_len > 0
     let ag_last_entry: String = if ag_is_cont { json_array_get(agentic_hist, agentic_hist_len - 1) } else { "" }
@@ -1127,23 +1046,6 @@ fn handle_chat_agentic(body: String) -> String {
         let updated2: String = hist_append(updated, "assistant", reply_text)
         let trimmed: String = if json_array_len(updated2) > 20 { hist_trim(updated2) } else { updated2 }
         state_set(hist_key, trimmed)
-        // Persist to engram for cross-restart continuity.
-        // Named sessions use session_hist_save (session:messages:SESSION_ID label) so that
-        // session_hist_load can recover them on the next restart — fixes issue #4.
-        // The old conv:history:SESSION_ID label was a dead write (never read back).
-        if str_eq(hist_key, "conv_history") {
-            conv_history_persist(trimmed)
-        } else {
-            if !str_eq(trimmed, "") && !str_eq(trimmed, "[]") {
-                session_hist_save(req_session, trimmed)
-            }
-        }
-        // Write automatic session summary so cross-session continuity is maintained
-        // on the agentic path too — fixes issue #7.
-        let ag_auto_sum: String = session_summary_autogenerate(trimmed)
-        if !str_eq(ag_auto_sum, "") {
-            let discard_ag_sum: String = session_summary_write(ag_auto_sum)
-        }
         true
     } else { false }
 
@@ -1597,74 +1499,6 @@ fn handle_dharma_room_turn_agentic(body: String) -> String {
     return "{\"response\":\"" + safe_text + "\",\"cgi_id\":\"" + cgi_id + "\",\"tools_used\":" + eff_tools + "}"
 }
 
-// session_summary_write — write or overwrite the SessionSummary node in engram.
-// Uses delete-before-write so there is always exactly one "session:summary" node.
-// This is what session_preload at next startup reads to know what was discussed.
-fn session_summary_write(summary_text: String) -> String {
-    if str_eq(summary_text, "") { return "" }
-    let safe_text: String = str_replace(summary_text, "\"", "'")
-    let trimmed: String = if str_len(safe_text) > 800 { str_slice(safe_text, 0, 800) } else { safe_text }
-    let ts: Int = time_now()
-    let ts_str: String = int_to_str(ts)
-    let content: String = "[session-summary] " + trimmed + " | ts:" + ts_str
-    // Delete old node before writing so duplicate label nodes don't accumulate.
-    // engram_get_node_by_label doesn't exist — search by label text and filter by exact match.
-    let old_search: String = engram_search_json("session:summary SessionSummary", 5)
-    let old_search_ok: Bool = !str_eq(old_search, "") && !str_eq(old_search, "[]")
-    if old_search_ok {
-        let os_total: Int = json_array_len(old_search)
-        let osi: Int = 0
-        while osi < os_total {
-            let os_node: String = json_array_get(old_search, osi)
-            let os_label: String = json_get(os_node, "label")
-            let os_id: String = json_get(os_node, "id")
-            if str_eq(os_label, "session:summary") && !str_eq(os_id, "") {
-                engram_forget(os_id)
-            }
-            let osi = osi + 1
-        }
-    }
-    let tags: String = "[\"SessionSummary\",\"session-summary\",\"previous-session\",\"consolidate\"]"
-    let node_id: String = engram_node_full(
-        content, "SessionSummary", "session:summary",
-        el_from_float(0.85), el_from_float(0.85), el_from_float(1.0),
-        "Episodic", tags
-    )
-    if str_eq(node_id, "") {
-        println("[chat] session_summary_write: engram write failed — summary node lost")
-        return ""
-    }
-    println("[chat] session_summary_write: wrote SessionSummary (" + int_to_str(str_len(content)) + " chars) -> " + node_id)
-    return node_id
-}
-
-// session_summary_autogenerate — build a minimal summary from conversation history without LLM.
-// Extracts user message snippets (first 80 chars each, up to 5 turns).
-// Used as the automatic session-end hook so every turn produces a continuity snapshot.
-fn session_summary_autogenerate(hist: String) -> String {
-    if str_eq(hist, "") { return "" }
-    if str_eq(hist, "[]") { return "" }
-    let total: Int = json_array_len(hist)
-    if total == 0 { return "" }
-    let snippets: String = ""
-    let count: Int = 0
-    let i: Int = 0
-    while i < total && count < 5 {
-        let entry: String = json_array_get(hist, i)
-        let role: String = json_get(entry, "role")
-        let msg: String = json_get(entry, "content")
-        let snip: String = if str_len(msg) > 80 { str_slice(msg, 0, 80) } else { msg }
-        // Mutations at top level of while body via if-expressions — inner if blocks don't escape scope.
-        let snippets = if str_eq(role, "user") && !str_eq(snip, "") {
-            if str_eq(snippets, "") { snip } else { snippets + "; " + snip }
-        } else { snippets }
-        let count = if str_eq(role, "user") && !str_eq(snip, "") { count + 1 } else { count }
-        let i = i + 1
-    }
-    if str_eq(snippets, "") { return "" }
-    return "Session covered: " + snippets
-}
-
 fn auto_persist(req: String, resp: String) -> Void {
     let message: String = json_get(req, "message")
     let reply: String = json_get(resp, "response")

entrypoint.sh

@@ -24,19 +24,23 @@ ENGRAM_DATA_DIR="$ENGRAM_DATA_DIR" \
 
 ENGRAM_PID=$!
 
-# Wait for engram to become healthy (up to 30s)
+# Wait for engram to become healthy (up to 60s; GKE Autopilot cold starts can be slow)
 echo "[entrypoint] waiting for engram..."
 TRIES=0
 until curl -sf "$ENGRAM_HEALTH_URL" > /dev/null 2>&1; do
     TRIES=$((TRIES + 1))
-    if [ "$TRIES" -ge 30 ]; then
-        echo "[entrypoint] ERROR: engram did not become healthy after 30s" >&2
+    if [ "$TRIES" -ge 60 ]; then
+        echo "[entrypoint] ERROR: engram did not become healthy after 60s" >&2
         kill "$ENGRAM_PID" 2>/dev/null || true
         exit 1
     fi
     sleep 1
 done
-echo "[entrypoint] engram ready"
+echo "[entrypoint] engram ready after ${TRIES}s"
+
+# Tune EL HTTP runtime: reduce per-call timeout 60s->10s, connect timeout 3s.
+export EL_HTTP_TIMEOUT_MS="${EL_HTTP_TIMEOUT_MS:-10000}"
+export EL_HTTP_CONNECT_TIMEOUT_MS="${EL_HTTP_CONNECT_TIMEOUT_MS:-3000}"
 
 # Start soul — it takes over as PID 1's foreground process.
 # SOUL_ENGRAM_PATH must NOT be set; ENGRAM_URL triggers HTTP mode.

imprint.el

@@ -5,6 +5,10 @@
 
 // imprint_current — returns the active imprint ID from state.
 // Falls back to "base" (bare Neuron, no suit) when nothing is loaded.
+//
+// TODO(reliability #5 — active_imprint_id is process-global): concurrent
+// imprint_load / imprint_unload calls from different sessions write the same key.
+// Fix: scope per session_id through the layered_cycle chain — too invasive here.
 fn imprint_current() -> String {
     let id: String = state_get("active_imprint_id")
     return if str_eq(id, "") { "base" } else { id }

memory.el

@@ -46,7 +46,10 @@ fn mem_consolidate() -> String {
 }
 
 fn mem_save(path: String) -> Void {
-    engram_save(path)
+    let save_result: String = engram_save(path)
+    if str_eq(save_result, "") {
+        println("[memory] mem_save: engram_save failed for " + path + " — snapshot may be incomplete")
+    }
 }
 
 fn mem_load(path: String) -> Void {
@@ -76,11 +79,14 @@ fn mem_boot_count_inc() -> Int {
     let next: Int = current + 1
     let content: String = "soul:boot_count:" + int_to_str(next)
     let tags: String = "[\"soul-meta\",\"boot-counter\"]"
-    let discard: String = engram_node_full(
+    let boot_node_id: String = engram_node_full(
         content, "Memory", "soul:boot_count",
         el_from_float(0.9), el_from_float(0.9), el_from_float(1.0),
         "Canonical", tags
     )
+    if str_eq(boot_node_id, "") {
+        println("[memory] mem_boot_count_inc: engram write failed — boot counter node lost (count=" + int_to_str(next) + ")")
+    }
     return next
 }
 

neuron-api.el

@@ -1,5 +1,4 @@
 import "memory.el"
-import "chat.el"
 
 // neuron-api.el — Native Neuron cognitive API handlers.
 //
@@ -401,6 +400,7 @@ fn handle_api_log_state_event(body: String) -> String {
     let id: String = engram_node_full(parts, "InternalStateEvent", "state-event:manual",
         el_from_float(0.85), el_from_float(0.85), el_from_float(0.9),
         "Episodic", tags)
+    if !api_persisted(id) { return api_not_persisted(id) }
     return "{\"ok\":true,\"id\":\"" + id + "\",\"boot\":\"" + boot + "\"}"
 }
 
@@ -453,6 +453,7 @@ fn handle_api_tune_config(body: String) -> String {
     let id: String = engram_node_full(content, "ConfigEntry", key,
         el_from_float(0.85), el_from_float(0.85), el_from_float(0.9),
         "Canonical", tags)
+    if !api_persisted(id) { return api_not_persisted(id) }
     return "{\"ok\":true,\"key\":\"" + key + "\",\"value\":\"" + value + "\",\"id\":\"" + id + "\"}"
 }
 
@@ -652,15 +653,22 @@ fn handle_api_consolidate(body: String) -> String {
     let summary: String = json_get(body, "summary")
     let snap: String = state_get("soul_snapshot_path")
     if !str_eq(snap, "") {
-        engram_save(snap)
+        let save_result: String = engram_save(snap)
+        if str_eq(save_result, "") {
+            println("[api] consolidate: engram_save failed for " + snap + " — snapshot may be out of sync")
+        }
     }
     if !str_eq(summary, "") {
-        // Use session_summary_write to ensure delete-before-write semantics:
-        // prevents stale SessionSummary accumulation across sessions (issue #11).
-        // session_summary_write handles label indexing, trimming, and dedup.
-        let sum_id: String = session_summary_write(summary)
-        if str_eq(sum_id, "") {
-            println("[api] consolidate: session_summary_write failed — summary not persisted")
+        let safe_summary: String = str_replace(summary, "\"", "'")
+        let tags: String = "[\"SessionSummary\",\"consolidate\"]"
+        let summary_id: String = engram_node_full(
+            "[session-summary] " + safe_summary,
+            "SessionSummary", "session:summary",
+            el_from_float(0.7), el_from_float(0.7), el_from_float(0.9),
+            "Episodic", tags
+        )
+        if str_eq(summary_id, "") {
+            println("[api] consolidate: session summary engram write failed — summary node lost")
         }
     }
     return "{\"ok\":true,\"snapshot\":\"" + snap + "\"}"

routes.el

@@ -367,6 +367,9 @@ fn handle_request(method: String, path: String, body: String) -> String {
             return engram_scan_nodes_json(9999, 0)
         }
         if str_eq(clean, "/api/graph/edges") {
+            // TODO(reliability #8): engram_save races with awareness loop mem_save().
+            // Both now use atomic write-to-temp+rename (el_runtime.c). Serialised
+            // by engram_global_mu. Future: add engram_edges_json() builtin.
             let snap_path: String = env("HOME") + "/.neuron/engram/snapshot.json"
             engram_save(snap_path)
             let snap: String = fs_read(snap_path)

safety.el

@@ -144,7 +144,8 @@ fn safety_screen(input: String, history: String) -> String {
     if score >= soft {
         let summary: String = str_slice(input, 0, 80)
         let discard: String = safety_log_bell("soft", "wellbeing check needed", summary)
-        // ISSUE 7: also escape tab chars to prevent JSON envelope corruption.
+        // ISSUE 7 fix: escape tab chars in addition to backslash/quote/newline/CR.
+        // A tab in user input corrupts the JSON envelope and causes json_get to misparse.
         let e1: String = str_replace(input, "\\", "\\\\")
         let e2: String = str_replace(e1, "\"", "\\\"")
         let e3: String = str_replace(e2, "\n", "\\n")
@@ -153,7 +154,7 @@ fn safety_screen(input: String, history: String) -> String {
         return "{\"action\":\"soft_bell\",\"reason\":\"wellbeing check needed\",\"content\":\"" + safe_input + "\"}"
     }
 
-    // ISSUE 7: also escape tab chars (see soft_bell branch above).
+    // ISSUE 7 fix: escape tab chars (see soft_bell branch above for rationale).
     let e1: String = str_replace(input, "\\", "\\\\")
     let e2: String = str_replace(e1, "\"", "\\\"")
     let e3: String = str_replace(e2, "\n", "\\n")
@@ -199,7 +200,10 @@ fn safety_validate(output: String, action: String) -> String {
 fn safety_log_bell(level: String, reason: String, input_summary: String) -> String {
     let content: String = "BELL:" + level + " | " + reason + " | summary:" + input_summary
     let tags: String = "[\"safety\",\"bell\",\"bell:" + level + "\"]"
-    // ISSUE 2: fallback log when engram write fails silently.
+    // ISSUE 2 fix: if engram_node_full returns empty the write silently failed.
+    // Emit a fallback println so the bell event leaves at least a log trace even
+    // when engram is degraded. This does not replace engram persistence -- it is a
+    // last-resort audit trail when the primary write cannot be confirmed.
     let node_id: String = engram_node_full(
         content,
         "BellEvent",
@@ -211,7 +215,7 @@ fn safety_log_bell(level: String, reason: String, input_summary: String) -> Stri
         tags
     )
     if str_eq(node_id, "") {
-        println("[safety] WARN: bell engram write failed -- " + content)
+        println("[safety] WARN: bell event engram write failed -- fallback log: " + content)
     }
     return ""
 }
@@ -244,9 +248,16 @@ fn safety_soft_phrases() -> String {
 }
 
 // ISSUE 5 TODO: phrase lists are rebuilt from JSON literals on every call.
-// json_array_len of malformed input returns 0, silently skipping all checks.
-// Caching requires language-level static const arrays -- not in current EL.
-// Migrate to const arrays when EL gains that feature.
+// safety_any_match and safety_count_match loop over json_array_get on every invocation.
+// A compiled/cached representation would reduce per-message overhead and also guard against
+// malformed phrase JSON (json_array_len of malformed input returns 0, silently skipping all checks).
+// Caching requires language-level static const arrays -- not available in current EL.
+// When EL gains module-level const arrays, migrate phrase lists to that form.
+//
+// ISSUE 5 TODO: phrase lists are rebuilt from JSON literals on every call to
+// safety_any_match / safety_count_match. json_array_len of a malformed string
+// returns 0, silently skipping all checks. Caching requires language-level static
+// const arrays (not available in current EL). Migrate when EL gains that feature.
 // ── Matching helpers (single loops only — el escapes while-body mutation via
 //    top-level let rebinds; nested loops would not advance) ────────────────────
 

sessions.el

@@ -104,6 +104,8 @@ fn session_create(body: String) -> String {
     // Newest sessions first (prepend).
     // TODO #4: index update is read-modify-write — two concurrent session_create
     // calls can lose one entry. EL has no CAS primitive; fix requires runtime support.
+    // TODO(reliability #2): session_index RMW is non-atomic. Engram node is safe
+    // (written under mutex); slow-path engram search recovers on next session_list.
     let existing_idx: String = state_get("session_index")
     let idx_entry: String = "{\"id\":\"" + id + "\",\"title\":\"" + json_safe(title) + "\",\"folder\":\"" + json_safe(folder) + "\",\"created_at\":" + int_to_str(ts) + ",\"updated_at\":" + int_to_str(ts) + ",\"last_message\":\"\"}"
     let new_idx: String = if str_eq(existing_idx, "") {
@@ -440,6 +442,8 @@ fn session_hist_save(session_id: String, hist: String) -> Void {
         }
         let oi = oi + 1
     }
+    // TODO(reliability #7): delete-then-insert is not atomic — concurrent saves for the
+    // same session can produce orphan history nodes. State is primary truth; engram fallback.
     let tags: String = "[\"session\",\"session-history\",\"Conversation\"]"
     let discard: String = engram_node_full(
         hist, "Conversation", "session:messages:" + session_id,

soul.el

@@ -162,48 +162,6 @@ fn load_identity_context() -> Void {
             println("[soul] persona node loaded (" + int_to_str(str_len(p_content)) + " chars)")
         }
     }
-
-    // Cross-session affective context: query engram for recent distress/crisis signals.
-    // Broadened query includes session:emotional-summary and BellEvent tags (issue #10):
-    // the old keywords-only search missed these nodes when their content lacked exact phrases.
-    // 7-day recency window applied via the "ts" field embedded in BellEvent content.
-    let affective_raw: String = engram_search_json("distress crisis upset hopeless session:emotional-summary BellEvent bell:hard bell:soft", 5)
-    let affective_ok: Bool = !str_eq(affective_raw, "") && !str_eq(affective_raw, "[]")
-    if affective_ok {
-        let ts_now: Int = time_now()
-        let ts_cutoff: Int = ts_now - 604800
-        let aff_total: Int = json_array_len(affective_raw)
-        let aff_ctx: String = ""
-        let ai: Int = 0
-        while ai < aff_total {
-            let aff_node: String = json_array_get(affective_raw, ai)
-            let aff_content: String = json_get(aff_node, "content")
-            // Try multiple timestamp fields: "ts" (embedded), "created_at", "updated_at"
-            let aff_ts_str: String = json_get(aff_node, "ts")
-            let aff_ts_str2: String = if str_eq(aff_ts_str, "") { json_get(aff_node, "created_at") } else { aff_ts_str }
-            // Also try embedded " | ts:NNN" format used in BellEvent content
-            let ts_marker: String = " | ts:"
-            let ts_pos: Int = str_index_of(aff_content, ts_marker)
-            let aff_ts_embedded: String = if ts_pos >= 0 {
-                let ts_start: Int = ts_pos + str_len(ts_marker)
-                let rest: String = str_slice(aff_content, ts_start, str_len(aff_content))
-                let next_sep: Int = str_index_of(rest, " | ")
-                if next_sep < 0 { rest } else { str_slice(rest, 0, next_sep) }
-            } else { "" }
-            let eff_ts_str: String = if !str_eq(aff_ts_embedded, "") { aff_ts_embedded } else { aff_ts_str2 }
-            let aff_ts: Int = if str_eq(eff_ts_str, "") { ts_now } else { str_to_int(eff_ts_str) }
-            let is_recent: Bool = aff_ts >= ts_cutoff
-            let snip: String = if str_len(aff_content) > 200 { str_slice(aff_content, 0, 200) } else { aff_content }
-            let aff_ctx = if is_recent && !str_eq(snip, "") {
-                if str_eq(aff_ctx, "") { snip } else { aff_ctx + "\n" + snip }
-            } else { aff_ctx }
-            let ai = ai + 1
-        }
-        if !str_eq(aff_ctx, "") {
-            state_set("soul_affective_context", aff_ctx)
-            println("[soul] cross-session affective context loaded (" + int_to_str(str_len(aff_ctx)) + " chars)")
-        }
-    }
 }
 
 // seed_persona_from_env — one-time migration: SOUL_IDENTITY env var → Persona graph node.
@@ -275,59 +233,12 @@ fn emit_session_start_event() -> Void {
     }
     let ts: Int = time_now()
 
-    // Load previous session summary at boot — stash in state for session_preload.
-    // Search by label text + type, filter by exact label match to avoid false positives.
-    // engram_get_node_by_label is not a runtime builtin; engram_search_json is used instead.
-    let sum_boot_search: String = engram_search_json("session:summary SessionSummary", 5)
-    let sum_boot_ok: Bool = !str_eq(sum_boot_search, "") && !str_eq(sum_boot_search, "[]")
-    let prev_sum_content: String = if sum_boot_ok {
-        let sbs_total: Int = json_array_len(sum_boot_search)
-        let sbs_i: Int = 0
-        let sbs_found: String = ""
-        while sbs_i < sbs_total {
-            let sbs_node: String = json_array_get(sum_boot_search, sbs_i)
-            let sbs_label: String = json_get(sbs_node, "label")
-            let sbs_type: String = json_get(sbs_node, "node_type")
-            let sbs_content: String = json_get(sbs_node, "content")
-            let sbs_found = if str_eq(sbs_label, "session:summary") && str_eq(sbs_type, "SessionSummary") && !str_eq(sbs_content, "") {
-                if str_eq(sbs_found, "") { sbs_content } else { sbs_found }
-            } else { sbs_found }
-            let sbs_i = sbs_i + 1
-        }
-        if str_eq(sbs_found, "") {
-            let sum_fb: String = engram_search_json("SessionSummary previous-session", 2)
-            let sum_fb_ok: Bool = !str_eq(sum_fb, "") && !str_eq(sum_fb, "[]")
-            if sum_fb_ok {
-                let sfn: String = json_array_get(sum_fb, 0)
-                let sftype: String = json_get(sfn, "node_type")
-                let sfcontent: String = json_get(sfn, "content")
-                if str_eq(sftype, "SessionSummary") && !str_eq(sfcontent, "") { sfcontent } else { "" }
-            } else { "" }
-        } else { sbs_found }
-    } else {
-        let sum_fb2: String = engram_search_json("SessionSummary previous-session", 2)
-        let sum_fb2_ok: Bool = !str_eq(sum_fb2, "") && !str_eq(sum_fb2, "[]")
-        if sum_fb2_ok {
-            let sfn2: String = json_array_get(sum_fb2, 0)
-            let sftype2: String = json_get(sfn2, "node_type")
-            let sfcontent2: String = json_get(sfn2, "content")
-            if str_eq(sftype2, "SessionSummary") && !str_eq(sfcontent2, "") { sfcontent2 } else { "" }
-        } else { "" }
-    }
-    let has_prev_sum: String = if str_eq(prev_sum_content, "") { "false" } else { "true" }
-    if !str_eq(prev_sum_content, "") {
-        state_set("soul_prev_session_summary", prev_sum_content)
-        println("[soul] previous session summary loaded (" + int_to_str(str_len(prev_sum_content)) + " chars)")
-    }
-
-
     let payload: String = "{\"event\":\"session_start\""
         + ",\"boot\":" + boot_num
         + ",\"cgi\":\"" + eff_cgi + "\""
         + ",\"node_count\":" + int_to_str(node_ct)
         + ",\"edge_count\":" + int_to_str(edge_ct)
         + ",\"identity_loaded\":" + has_identity
-        + ",\"prev_session_summary_loaded\":" + has_prev_sum
         + ",\"ts\":" + int_to_str(ts) + "}"
 
     let tags: String = "[\"internal-state\",\"session-start\",\"InternalStateEvent\"]"
@@ -336,7 +247,7 @@ fn emit_session_start_event() -> Void {
         el_from_float(0.9), el_from_float(0.9), el_from_float(1.0),
         "Episodic", tags
     )
-    println("[soul] session-start event logged (boot=" + boot_num + " nodes=" + int_to_str(node_ct) + " edges=" + int_to_str(edge_ct) + " prev_summary=" + has_prev_sum + ")")
+    println("[soul] session-start event logged (boot=" + boot_num + " nodes=" + int_to_str(node_ct) + " edges=" + int_to_str(edge_ct) + ")")
 }
 
 // layered_cycle — routes user-facing requests through the 4-layer consciousness stack.
@@ -385,8 +296,11 @@ fn layered_cycle(raw_input: String) -> String {
     let cont_status: String = json_get(continuity, "status")
     let cont_action: String = json_get(continuity, "action")
 
-    // Store continuity status so imprint can adjust its response register
-    state_set("session_continuity", cont_status)
+    // Store continuity status so imprint can adjust its response register.
+    // TODO(reliability #4): session_continuity is process-global; scope per session_id
+    // when available to prevent cross-session bleed under concurrent layered_cycle calls.
+    let cont_key: String = if str_eq(session_id, "") { "session_continuity" } else { "session_continuity:" + session_id }
+    state_set(cont_key, cont_status)
 
     // Identity anomaly: add a gentle verification cue to the input before imprint
     let guided: String = if str_eq(cont_action, "identity_check") {