diff --git a/README.md b/README.md
index 48dd60e..242277d 100644
--- a/README.md
+++ b/README.md
@@ -47,6 +47,13 @@ find the hostname in it yourself.
 The certificates and their provenance are documented in [`certs/PROVENANCE.md`](certs/PROVENANCE.md),
 including the command each was captured with.
 
+The address input accepts ASCII DNS hosts and `scheme://authority` URLs, with
+userinfo interpreted only inside the authority. An `@` in a path, query or
+fragment does not change the hostname. This is a bounded teaching parser, not
+the complete WHATWG URL implementation. A mismatched-address badge preserves
+the pasted string and wraps long fragments or query values without widening
+the page, including at the 320px reflow floor.
+
 ## Exhibits
 
 The **guided lesson is the default**: five steps, one question and one action each, with an
diff --git a/e2e/claims.spec.ts b/e2e/claims.spec.ts
index d16ab37..0fd446f 100644
--- a/e2e/claims.spec.ts
+++ b/e2e/claims.spec.ts
@@ -166,6 +166,29 @@ test.describe('promise 2, the name check, re-derived independently', () => {
     })
   }
 
+  for (const width of [320, 390, 1280]) {
+    test(`pasted URL badges preserve their complete text without page overflow at ${width}px`, async ({ page }) => {
+      await page.setViewportSize({ width, height: 900 })
+      await bootExplore(page)
+      for (const address of [
+        'https://other.example/#user@github.com',
+        'https://other.example/?email=user@github.com',
+        `https://other.example/?tracking=${'x'.repeat(200)}@github.com`,
+      ]) {
+        const expected = new URL(address).hostname === 'github.com' ? 'pass' : 'fail'
+        await page.locator('#address-input').fill(expected === 'pass' ? 'other.example' : 'github.com')
+        await expect(page.locator('[data-verdict="promise-name"]')).toHaveAttribute('data-result', expected === 'pass' ? 'fail' : 'pass')
+        await page.locator('#address-input').fill(address)
+        await expect(page.locator('[data-verdict="promise-name"]')).toHaveAttribute('data-result', expected)
+        const badge = page.locator('.badges .badge').filter({ hasText: address })
+        await expect(badge).toBeVisible()
+        await expect(badge).toContainText(address)
+        const geometry = await page.evaluate(() => ({ document: document.documentElement.scrollWidth, viewport: innerWidth }))
+        expect(geometry.document).toBeLessThanOrEqual(geometry.viewport + 1)
+      }
+    })
+  }
+
   test('a failing name check names the actual cause', async ({ page }) => {
     await bootExplore(page)
     await page.locator('#address-input').fill('evil.example')
diff --git a/src/style.css b/src/style.css
index 9a84f83..e82b6b6 100644
--- a/src/style.css
+++ b/src/style.css
@@ -471,6 +471,7 @@ details > .details-body { padding: 0 0.8rem 0.8rem; }
 .badges { display: flex; flex-wrap: wrap; gap: 0.35rem; margin: 0.6rem 0 0; padding: 0; list-style: none; }
 .badge {
   font-family: var(--mono); font-size: 0.72rem; font-weight: 700; letter-spacing: 0.03em;
+  overflow-wrap: anywhere;
   padding: 0.2rem 0.5rem; border: 1px solid var(--alarm-ink); border-radius: 999px;
   color: var(--alarm-ink); background: var(--alarm-wash);
 }