diff --git a/arborist_viz/routes.py b/arborist_viz/routes.py
index 10c1a32..4a99ee0 100644
--- a/arborist_viz/routes.py
+++ b/arborist_viz/routes.py
@@ -59,9 +59,14 @@ def includeme(config):
     config.add_route("sessions_list", "/sessions")
     config.add_route("sessions_find", "/sessions/find")
     config.add_route("sessions_tree", "/sessions/{sid}")
+    config.add_route("cache_key_page", "/cache/{cache_key}")
     config.add_route("api_sessions_list", "/api/sessions")
     config.add_route("api_sessions_find", "/api/sessions/find")
     config.add_route("api_sessions_tree", "/api/sessions/{sid}")
+    # Sessions-shard view of a providence cache_key (every session node
+    # referencing it). Distinct from /api/cache/ which targets the
+    # providence_cache row itself (ticket #000069 §13 §6.7).
+    config.add_route("api_session_cache_key", "/api/cache-key/{cache_key}")
 
     # SSE — §3-corrected replaces WS routes with text/event-stream.
     config.add_route("sse_audit_live", "/sse/audit/live")
diff --git a/arborist_viz/static/css/viz.css b/arborist_viz/static/css/viz.css
index 9a96e25..a83048a 100644
--- a/arborist_viz/static/css/viz.css
+++ b/arborist_viz/static/css/viz.css
@@ -673,3 +673,70 @@ code, pre { font-family: var(--mono); font-size: 12px; }
 .cmd-cite { font-size: 0.75em; opacity: 0.7;
   padding: 0.05em 0.4em; border-radius: 0.2em;
   background: rgba(255,255,255,0.06); }
+
+/* ---- node cards + answer + metadata (richer tree views) -------------- */
+
+.cmd-panel-wide { max-width: none; padding: 1.5em 2em; }
+
+.cmd-hash-block { word-break: break-all; font-size: 0.85em; opacity: 0.85; }
+
+.cmd-node-card {
+  background: rgba(255,255,255,0.03);
+  border: 1px solid rgba(255,255,255,0.08);
+  border-radius: 0.3em;
+  padding: 0.8em 1em;
+  margin: 0.4em 0;
+}
+.cmd-node-card-head {
+  display: flex; gap: 0.6em; align-items: baseline; flex-wrap: wrap;
+  margin-bottom: 0.4em;
+}
+.cmd-node-q {
+  font-size: 1.05em; font-weight: 500;
+  margin: 0.3em 0 0.5em 0;
+}
+.cmd-current-pill, .cmd-branch-pill {
+  font-size: 0.7em; padding: 0.05em 0.5em;
+  border-radius: 0.2em; font-weight: 600;
+  text-transform: uppercase; letter-spacing: 0.05em;
+}
+.cmd-current-pill { background: rgba(120, 200, 255, 0.25); color: #8af; }
+.cmd-branch-pill { background: rgba(220, 180, 80, 0.25); color: #db8; }
+
+.cmd-node-answer summary,
+.cmd-node-meta summary {
+  cursor: pointer; opacity: 0.7; font-size: 0.85em;
+  padding: 0.3em 0; user-select: none;
+}
+.cmd-node-answer[open] summary,
+.cmd-node-meta[open] summary { opacity: 1; }
+.cmd-answer-pre {
+  background: rgba(0,0,0,0.25);
+  padding: 0.8em 1em;
+  border-left: 2px solid rgba(120, 200, 255, 0.4);
+  border-radius: 0.2em;
+  font-size: 0.85em;
+  line-height: 1.5;
+  white-space: pre-wrap;
+  word-break: break-word;
+  overflow-x: auto;
+  max-height: 600px;
+  overflow-y: auto;
+}
+
+.cmd-meta-dl {
+  display: grid;
+  grid-template-columns: max-content 1fr;
+  gap: 0.2em 1em;
+  font-size: 0.85em;
+  padding: 0.5em 0;
+}
+.cmd-meta-dl dt { opacity: 0.65; }
+.cmd-meta-dl dd { margin: 0; word-break: break-all; }
+.cmd-meta-dl code { font-size: 0.95em; }
+
+.cmd-tree-current > .cmd-node-card { border-color: rgba(120, 200, 255, 0.5); }
+.cmd-tree-branch > .cmd-node-card { border-color: rgba(220, 180, 80, 0.5); }
+
+/* Override the tree-line styles (old layout) — cards replace them. */
+.cmd-tree-current > .cmd-tree-line::after { content: none; }
diff --git a/arborist_viz/templates/cache_key.jinja2 b/arborist_viz/templates/cache_key.jinja2
new file mode 100644
index 0000000..a555117
--- /dev/null
+++ b/arborist_viz/templates/cache_key.jinja2
@@ -0,0 +1,52 @@
+{% extends "base.jinja2" %}
+{% block body %}
+<section class="cmd-panel">
+  <header class="cmd-panel-head">
+    <h1>cache_key</h1>
+    <p class="cmd-hash-block"><code class="cmd-hash">{{ cache_key }}</code></p>
+    <p class="cmd-panel-sub">
+      {{ hits|length }} session node(s) reference this providence cache entry —
+      a cache hit reused across {{ hits|map(attribute='sid')|unique|list|length }} session(s).
+    </p>
+    <p><a href="/sessions">← all sessions</a> · <a href="/api/cache-key/{{ cache_key }}">JSON</a></p>
+  </header>
+
+  {% if hits %}
+    {% set first = hits[0] %}
+    <article class="cmd-node-card">
+      <header class="cmd-node-card-head">
+        <span class="cmd-tree-audit cmd-audit-{{ first.audit_mode|lower }}">{{ first.audit_mode }}</span>
+        <span class="cmd-node-q">{{ first.question }}</span>
+      </header>
+      {% if first.cited_titles %}
+      <div class="cmd-tree-cites">
+        {% for t in first.cited_titles %}<span class="cmd-cite">{{ t }}</span>{% endfor %}
+      </div>
+      {% endif %}
+      <details class="cmd-node-answer" open>
+        <summary>answer</summary>
+        <pre class="cmd-answer-pre">{{ first.answer_text }}</pre>
+      </details>
+    </article>
+
+    <h2>Referenced by</h2>
+    <table class="cmd-table">
+      <thead>
+        <tr><th>bates</th><th>session</th><th>audit</th><th>created</th></tr>
+      </thead>
+      <tbody>
+        {% for n in hits %}
+        <tr>
+          <td><a href="/sessions/{{ n.sid }}"><code>{{ n.bates }}</code></a></td>
+          <td><code>{{ n.sid }}</code></td>
+          <td><span class="cmd-tree-audit cmd-audit-{{ n.audit_mode|lower }}">{{ n.audit_mode }}</span></td>
+          <td>{{ n.created_at }}</td>
+        </tr>
+        {% endfor %}
+      </tbody>
+    </table>
+  {% else %}
+    <p class="cmd-empty">no session nodes reference this cache_key</p>
+  {% endif %}
+</section>
+{% endblock %}
diff --git a/arborist_viz/templates/sessions_tree.jinja2 b/arborist_viz/templates/sessions_tree.jinja2
index 110fb65..726014c 100644
--- a/arborist_viz/templates/sessions_tree.jinja2
+++ b/arborist_viz/templates/sessions_tree.jinja2
@@ -2,18 +2,50 @@
 
 {% macro render_node(node, kids_of, branch_set, current_bates, this_sid, depth=0) -%}
   <li class="cmd-tree-node {% if node.bates == current_bates %}cmd-tree-current{% endif %} {% if node.bates in branch_set %}cmd-tree-branch{% endif %}">
-    <div class="cmd-tree-line">
-      <span class="cmd-tree-bates"><code>{{ node.bates }}</code></span>
-      <span class="cmd-tree-audit cmd-audit-{{ node.audit_mode|lower }}">{{ node.audit_mode }}</span>
-      {% if node.sid != this_sid %}<span class="cmd-tree-from">[from {{ node.sid }}]</span>{% endif %}
-      {% if node.label %}<span class="cmd-tree-label">{{ '{' + node.label + '}' }}</span>{% endif %}
-      <span class="cmd-tree-q">{{ (node.question or '')[:120] }}</span>
-    </div>
-    {% if node.cited_titles %}
-    <div class="cmd-tree-cites">
-      {% for t in node.cited_titles %}<span class="cmd-cite">{{ t }}</span>{% endfor %}
-    </div>
-    {% endif %}
+    <article class="cmd-node-card">
+      <header class="cmd-node-card-head">
+        <code class="cmd-tree-bates">{{ node.bates }}</code>
+        <span class="cmd-tree-audit cmd-audit-{{ node.audit_mode|lower }}">{{ node.audit_mode }}</span>
+        {% if node.sid != this_sid %}<span class="cmd-tree-from">[from {{ node.sid }}]</span>{% endif %}
+        {% if node.label %}<span class="cmd-tree-label">{{ '{' + node.label + '}' }}</span>{% endif %}
+        {% if node.bates == current_bates %}<span class="cmd-current-pill">current</span>{% endif %}
+        {% if node.bates in branch_set %}<span class="cmd-branch-pill">branch</span>{% endif %}
+      </header>
+
+      <div class="cmd-node-q">{{ node.question }}</div>
+
+      {% if node.cited_titles %}
+      <div class="cmd-tree-cites">
+        {% for t in node.cited_titles %}<span class="cmd-cite">{{ t }}</span>{% endfor %}
+      </div>
+      {% endif %}
+
+      {% if node.answer_text %}
+      <details class="cmd-node-answer">
+        <summary>answer ({{ node.answer_text|length }} chars)</summary>
+        <pre class="cmd-answer-pre">{{ node.answer_text }}</pre>
+      </details>
+      {% endif %}
+
+      <details class="cmd-node-meta">
+        <summary>hashes / metadata</summary>
+        <dl class="cmd-meta-dl">
+          <dt>cache_key</dt>
+          <dd>{% if node.cache_key %}<a href="/cache/{{ node.cache_key }}"><code class="cmd-hash">{{ node.cache_key }}</code></a>{% else %}<em>(none — canonical_projection)</em>{% endif %}</dd>
+          <dt>node_hash</dt>
+          <dd><code class="cmd-hash">{{ node.node_hash }}</code></dd>
+          <dt>subtree_hash</dt>
+          <dd><code class="cmd-hash">{{ node.subtree_hash }}</code></dd>
+          <dt>created</dt>
+          <dd>{{ node.created_at }}</dd>
+          {% if node.parent_bates %}
+          <dt>parent</dt>
+          <dd><code>{{ node.parent_bates }}</code></dd>
+          {% endif %}
+        </dl>
+      </details>
+    </article>
+
     {% set kids = kids_of.get(node.bates, []) %}
     {% if kids %}
     <ul class="cmd-tree-children">
@@ -26,27 +58,27 @@
 {%- endmacro %}
 
 {% block body %}
-<section class="cmd-panel">
+<section class="cmd-panel cmd-panel-wide">
   <header class="cmd-panel-head">
-    <h1>session <code>{{ session.sid }}</code></h1>
+    <h1>session <code>{{ session.sid }}</code>{% if session.label %} <span class="cmd-tree-label">{{ '{' + session.label + '}' }}</span>{% endif %}</h1>
     <p class="cmd-panel-sub">
       {{ session.n_nodes }} node(s) · {{ branches|length }} branch point(s) ·
-      <code class="cmd-hash">root={{ session.session_root }}</code> ·
-      current → <code>{{ session.current_bates }}</code>
+      current → <a href="#node-{{ session.current_bates }}"><code>{{ session.current_bates }}</code></a>
     </p>
+    <p class="cmd-hash-block">root <code class="cmd-hash">{{ session.session_root }}</code></p>
     <p><a href="/sessions">← all sessions</a> · <a href="/api/sessions/{{ session.sid }}">JSON</a></p>
   </header>
 
   {% set kids_of = children %}
   {% set root_node = nodes[0] if nodes and nodes[0].seq == 0 else None %}
-  {% if root_node %}
+  {% if root_node and kids_of.get(root_node.bates) %}
     <ul class="cmd-tree">
       {% for child in kids_of.get(root_node.bates, []) %}
         {{ render_node(child, kids_of, branches, session.current_bates, session.sid) }}
       {% endfor %}
     </ul>
   {% else %}
-    <p class="cmd-empty">empty session</p>
+    <p class="cmd-empty">empty session — no turns yet. <code>make session SID={{ session.sid }}</code> to continue.</p>
   {% endif %}
 </section>
 {% endblock %}
diff --git a/arborist_viz/views/roots.py b/arborist_viz/views/roots.py
index e760008..4cfe007 100644
--- a/arborist_viz/views/roots.py
+++ b/arborist_viz/views/roots.py
@@ -192,22 +192,72 @@ def get_lattice(request):
 
 @view_config(route_name="api_resolve", request_method="GET")
 def resolve_hash(request):
-    """Drop-a-hash dispatcher. Returns whichever arborist object owns the hash."""
-    if request.shards is None:
-        return _no_shard()
+    """Drop-a-hash dispatcher. Returns whichever arborist object owns the hash.
+
+    Resolution order: corpus shards first (document_root / leaf_hash /
+    audit_event / merkle_interior / qa cache_key / context_root /
+    run_dag_root), then sessions shard (cache_key referenced by N
+    session nodes; node_hash / subtree_hash on a session node).
+    """
     h = request.matchdict["hex_hash"].strip().lower()
     if not h or len(h) > 128 or not all(c in "0123456789abcdef" for c in h):
         return _json({"error": "not_hex", "hash": h}, status=400)
-    res = request.shards.resolve(h)
-    # The browser still needs a /url to navigate to — synthesize from kind.
-    url = _nav_url(res)
-    return _json({
-        "kind": res.kind,
-        "hash": res.hash,
-        "shard": res.shard_path,
-        "url": url,
-        **res.extra,
-    })
+
+    # First: corpus shards (when configured).
+    if request.shards is not None:
+        res = request.shards.resolve(h)
+        if res.kind != "unknown":
+            return _json({
+                "kind": res.kind, "hash": res.hash,
+                "shard": res.shard_path, "url": _nav_url(res),
+                **res.extra,
+            })
+
+    # Second: sessions shard. cache_key OR node_hash OR subtree_hash.
+    sessions = request.sessions
+    if sessions is not None and sessions.is_open:
+        hits = sessions.find_by_cache_key(h)
+        if hits:
+            first = hits[0]
+            return _json({
+                "kind": "session_cache_key",
+                "hash": h,
+                "shard": sessions.path,
+                "n_session_nodes": len(hits),
+                "sids": sorted({n.sid for n in hits}),
+                "bates_list": [n.bates for n in hits],
+                "audit_modes": sorted({n.audit_mode for n in hits}),
+                "question": first.question,
+                "url": "/cache/{0}".format(h),
+            })
+        # node_hash / subtree_hash search: scan one row.
+        # (No index on these; rare path — direct query.)
+        try:
+            row = sessions._conn.execute(  # type: ignore[attr-defined]
+                "SELECT bates, sid, audit_mode, question, node_hash, "
+                "       subtree_hash FROM nodes "
+                "WHERE node_hash=? OR subtree_hash=? LIMIT 1",
+                (h, h),
+            ).fetchone()
+        except Exception:
+            row = None
+        if row:
+            kind = (
+                "session_node_hash" if row["node_hash"] == h
+                else "session_subtree_hash"
+            )
+            return _json({
+                "kind": kind,
+                "hash": h,
+                "shard": sessions.path,
+                "bates": row["bates"],
+                "sid": row["sid"],
+                "audit_mode": row["audit_mode"],
+                "question": row["question"],
+                "url": "/sessions/{0}".format(row["sid"]),
+            })
+
+    return _json({"kind": "unknown", "hash": h, "url": "/"})
 
 
 def _nav_url(res) -> str:
diff --git a/arborist_viz/views/sessions.py b/arborist_viz/views/sessions.py
index 95555cb..2a3400c 100644
--- a/arborist_viz/views/sessions.py
+++ b/arborist_viz/views/sessions.py
@@ -81,6 +81,38 @@ def sessions_tree(request):
     return ctx
 
 
+@view_config(route_name="cache_key_page", renderer="cache_key.jinja2")
+def cache_key_page(request):
+    """Show every session node referencing a given providence cache_key.
+    A cache hit reused across sessions/turns lights up here."""
+    sessions = request.sessions
+    cache_key = request.matchdict["cache_key"].strip().lower()
+    hits = (
+        sessions.find_by_cache_key(cache_key)
+        if (sessions and sessions.is_open) else []
+    )
+    ctx = _sessions_ctx(request)
+    ctx["title"] = f"cache_key {cache_key[:12]}… — Arborist VIZ"
+    ctx["cache_key"] = cache_key
+    ctx["hits"] = hits
+    return ctx
+
+
+@view_config(route_name="api_session_cache_key", renderer="json")
+def api_cache_key(request):
+    sessions = request.sessions
+    cache_key = request.matchdict["cache_key"].strip().lower()
+    hits = (
+        sessions.find_by_cache_key(cache_key)
+        if (sessions and sessions.is_open) else []
+    )
+    return {
+        "cache_key": cache_key,
+        "n_session_nodes": len(hits),
+        "nodes": [_node_to_json(n) for n in hits],
+    }
+
+
 @view_config(route_name="sessions_find", renderer="sessions_find.jinja2")
 def sessions_find(request):
     sessions = request.sessions