diff --git a/frontend/packages/swarm-ui/src/ui/confirm-dialog/ConfirmDialog.css b/frontend/packages/swarm-ui/src/ui/confirm-dialog/ConfirmDialog.css
index bec51820..582fc3ad 100644
--- a/frontend/packages/swarm-ui/src/ui/confirm-dialog/ConfirmDialog.css
+++ b/frontend/packages/swarm-ui/src/ui/confirm-dialog/ConfirmDialog.css
@@ -1,5 +1,9 @@
 /* <ConfirmDialog> — body + button-row layout only; `Dialog.css` owns the
-   surrounding modal chrome, `Button.css` owns the buttons themselves. */
+   surrounding modal chrome, `Button.css` owns the buttons themselves.
+   This `max-width` is the ONLY width decision for a confirm dialog now
+   — `Dialog`'s shell sizes to `fit-content` (see Dialog.css), so
+   whatever this wrapper caps itself at is exactly how wide the whole
+   dialog renders, no second number to keep in sync. */
 .confirm-dialog {
   display: flex;
   flex-direction: column;
diff --git a/frontend/packages/swarm-ui/src/ui/dialog/Dialog.css b/frontend/packages/swarm-ui/src/ui/dialog/Dialog.css
index ee4d4b96..49706dca 100644
--- a/frontend/packages/swarm-ui/src/ui/dialog/Dialog.css
+++ b/frontend/packages/swarm-ui/src/ui/dialog/Dialog.css
@@ -1,17 +1,26 @@
-/* <Dialog> — native `<dialog>` styling. Sized to comfortably hold the
-   create-agent form's own two-panel layout (which wraps to single-
-   column below its existing 16em-per-column threshold — see
-   CreateAgentForm.css — so this doesn't need to special-case that). */
+/* <Dialog> — native `<dialog>` styling. Sizes to its own content
+   (`width: fit-content`, matching a native `<dialog>`'s own UA
+   default) rather than a fixed width — each caller's content decides
+   how wide the shell gets, capped at `min(90vw, 44em)` so nothing
+   overflows a narrow viewport or balloons unreasonably wide on
+   desktop. The create-agent form's two-panel layout is wide enough to
+   hit that cap on its own (same rendered width as a fixed 44em);
+   `ConfirmDialog`'s shorter paragraph settles at its own narrower
+   intrinsic width instead — no second width mode needed (a forced
+   `width` was the actual root cause, one level above where a
+   per-caller flag would've patched it, caught in review). */
 .ui-dialog {
   /* No sitewide `box-sizing: border-box` reset exists — without this,
-     the padding + border below add ON TOP of `width: 90vw` rather than
-     being carved out of it, overflowing a real phone-width viewport
-     (measured: 401px rendered against a 390px viewport). Caught via a
-     real screenshot at 390px, not assumed. */
+     the padding + border below add ON TOP of the content width rather
+     than being carved out of it, overflowing a real phone-width
+     viewport (measured: 401px rendered against a 390px viewport back
+     when this was a fixed `width: 90vw`). Still needed with
+     `fit-content` sizing — `max-width` has the same carving-out
+     requirement `width` did. */
   box-sizing: border-box;
   position: relative;
-  width: 90vw;
-  max-width: 44em;
+  width: fit-content;
+  max-width: min(90vw, 44em);
   max-height: 85vh;
   overflow: auto;
   padding: 1.5em;