diff --git a/pyproject.toml b/pyproject.toml
index 028a3bb..c4d4a33 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "ratatoskr"
-version = "0.20.16"
+version = "0.20.17"
 description = "Worldtree Conversation API debug TUI — multi-pane observability dashboard"
 readme = "README.md"
 requires-python = ">=3.12"
diff --git a/src/ratatoskr/web/static/index.html b/src/ratatoskr/web/static/index.html
index b949369..2ead4d1 100644
--- a/src/ratatoskr/web/static/index.html
+++ b/src/ratatoskr/web/static/index.html
@@ -178,6 +178,29 @@ kbd {
 #app.live { display: flex; }
 #cols { flex: 1; display: flex; min-height: 0; }
 
+/* ---- collapsible debug panes (independent left/right; #center reflows to fill) ---- */
+.pane-collapse {
+  width: 22px; height: 22px; display: flex; align-items: center; justify-content: center;
+  background: transparent; border: 1px solid var(--border-subtle); border-radius: var(--radius-sm);
+  color: var(--fg-3); cursor: pointer; flex: 0 0 auto; font-size: 13px; line-height: 1; padding: 0;
+}
+.pane-collapse:hover { background: var(--bg-2); color: var(--fg-0); border-color: var(--border-default); }
+.ac-head-row { display: flex; align-items: center; justify-content: space-between; position: relative; }
+/* re-open strip: hidden while the pane is open, becomes the full-height handle when collapsed */
+.pane-reopen { display: none; }
+#cols.left-collapsed  #rail-left      { width: 22px !important; flex-basis: 22px !important; overflow: hidden; }
+#cols.right-collapsed #affect-console { width: 22px !important; flex-basis: 22px !important; overflow: hidden; }
+#cols.left-collapsed  #rail-left      > *:not(.pane-reopen) { display: none; }
+#cols.right-collapsed #affect-console > *:not(.pane-reopen) { display: none; }
+#cols.left-collapsed  #rail-left      .pane-reopen,
+#cols.right-collapsed #affect-console .pane-reopen {
+  display: flex; flex: 1; width: 100%; align-items: center; justify-content: center;
+  background: transparent; border: none; color: var(--fg-3); cursor: pointer; font-size: 13px;
+}
+#cols.left-collapsed  #rail-left      .pane-reopen:hover,
+#cols.right-collapsed #affect-console .pane-reopen:hover { background: var(--bg-2); color: var(--fg-0); }
+#cols.right-collapsed #affect-resizer { display: none; }
+
 /* eyebrow — mono uppercase wide-tracked (Australis signature) */
 .eyebrow {
   font-family: var(--font-mono); font-size: 9.5px;
@@ -554,6 +577,7 @@ body.cot-hidden #cot-toggle { border-color: rgba(66,220,209,0.55); color: var(--
           <svg class="i-sun" width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.75" stroke-linecap="round" stroke-linejoin="round"><circle cx="12" cy="12" r="4"></circle><path d="M12 2v2M12 20v2M4.9 4.9l1.4 1.4M17.7 17.7l1.4 1.4M2 12h2M20 12h2M4.9 19.1l1.4-1.4M17.7 6.3l1.4-1.4"></path></svg>
           <svg class="i-moon" width="15" height="15" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.75" stroke-linecap="round" stroke-linejoin="round"><path d="M21 12.8A9 9 0 1 1 11.2 3a7 7 0 0 0 9.8 9.8z"></path></svg>
         </button>
+        <button class="pane-collapse" id="collapse-left" title="Collapse debug rail">‹</button>
       </div>
 
       <div id="conn" data-state="offline">
@@ -576,6 +600,7 @@ body.cot-hidden #cot-toggle { border-color: rgba(66,220,209,0.55); color: var(--
         <span class="eyebrow off" id="bifrost-head">⇄ bifrost · not bound</span>
         <div id="bifrost-body"><div class="bf-note">observe-only session</div></div>
       </div>
+      <button class="pane-reopen" id="reopen-left" title="Expand debug rail">›</button>
     </aside>
 
     <!-- ══════════ CENTER · conversation ══════════ -->
@@ -613,7 +638,10 @@ body.cot-hidden #cot-toggle { border-color: rgba(66,220,209,0.55); color: var(--
       </defs></svg>
       <div class="ac-sec" id="ac-dominant">
         <div class="glow"></div>
-        <div class="eyebrow">affect · dominant</div>
+        <div class="ac-head-row">
+          <div class="eyebrow">affect · dominant</div>
+          <button class="pane-collapse" id="collapse-right" title="Collapse affect console">›</button>
+        </div>
         <div id="dominant-emotion" class="muted">—</div>
         <div id="emotions-active"></div>
       </div>
@@ -711,6 +739,7 @@ body.cot-hidden #cot-toggle { border-color: rgba(66,220,209,0.55); color: var(--
         <span class="grow"></span>
         <span id="version">ratatoskr —</span>
       </div>
+      <button class="pane-reopen" id="reopen-right" title="Expand affect console">‹</button>
     </aside>
   </div>
 </div>
@@ -1948,6 +1977,24 @@ async function cancelTurn() {
   });
 })();
 
+// ---- collapsible debug panes (independent left / right; state persists) ----
+(function () {
+  const cols = $("cols");
+  function apply(side, collapsed) {
+    cols.classList.toggle(side + "-collapsed", collapsed);
+    try { localStorage.setItem("ratatoskr-" + side + "-collapsed", collapsed ? "1" : "0"); } catch (_) {}
+  }
+  let left = false, right = false;
+  try { left = localStorage.getItem("ratatoskr-left-collapsed") === "1"; } catch (_) {}
+  try { right = localStorage.getItem("ratatoskr-right-collapsed") === "1"; } catch (_) {}
+  cols.classList.toggle("left-collapsed", left);
+  cols.classList.toggle("right-collapsed", right);
+  $("collapse-left").addEventListener("click", () => apply("left", true));
+  $("reopen-left").addEventListener("click", () => apply("left", false));
+  $("collapse-right").addEventListener("click", () => apply("right", true));
+  $("reopen-right").addEventListener("click", () => apply("right", false));
+})();
+
 // ---- composer auto-grow + keyboard ----
 $("prompt-input").addEventListener("input", (e) => {
   const el = e.target;
diff --git a/uv.lock b/uv.lock
index 6a3d47e..e9c64b5 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1052,7 +1052,7 @@ wheels = [
 
 [[package]]
 name = "ratatoskr"
-version = "0.20.16"
+version = "0.20.17"
 source = { editable = "." }
 dependencies = [
     { name = "httpx" },