diff --git a/scripts/ci-guards/no-unbound-label-baseline.txt b/scripts/ci-guards/no-unbound-label-baseline.txt
new file mode 100644
index 0000000..94361d4
--- /dev/null
+++ b/scripts/ci-guards/no-unbound-label-baseline.txt
@@ -0,0 +1 @@
+132
diff --git a/scripts/ci-guards/no-unbound-label.sh b/scripts/ci-guards/no-unbound-label.sh
new file mode 100755
index 0000000..562d1b1
--- /dev/null
+++ b/scripts/ci-guards/no-unbound-label.sh
@@ -0,0 +1,94 @@
+#!/usr/bin/env bash
+# Phase 5 closure (UX-H4 regression gate): fail the build when a new
+# <label> element ships in production tsx without htmlFor= or a wrapping
+# <FormField> primitive (which auto-emits htmlFor via useId()).
+#
+# Pre-Phase-5: 139 <label> tags, 6 with htmlFor, 0 inputs with id —
+# WCAG 1.3.1 fails on ~99% of form fields. The FormField primitive
+# (web/src/components/FormField.tsx) closes new label/input pairs by
+# construction; this guard prevents reintroducing unbound labels in
+# untouched parts of the codebase.
+#
+# Grace period: during the Phase 5 migration we expect ~133 existing
+# unbound labels to stay in place until each owning page migrates
+# through. They live in the allowlist file alongside this script
+# (no-unbound-label-exceptions.txt). Each migration deletes the
+# corresponding line; when the allowlist is empty, this guard becomes
+# strictly enforcing and the allowlist file should be removed.
+#
+# Algorithm:
+#   1. Count current unbound labels (labels NOT preceded by htmlFor= on
+#      the same line OR within the wrapping JSX block).
+#   2. Compare against the allowlist's recorded count. If today's count
+#      is HIGHER than the allowlist baseline, a new unbound label was
+#      added — fail with the diff.
+#   3. If today's count is LOWER, congratulate and remind to update
+#      the baseline.
+#
+# Strict mode: pass `--strict` to fail on any unbound label, ignoring
+# the allowlist. Use once the allowlist is empty.
+set -euo pipefail
+
+# Resolve script dir BEFORE cd so baseline path stays valid.
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+BASELINE_FILE="$SCRIPT_DIR/no-unbound-label-baseline.txt"
+
+cd "$SCRIPT_DIR/../../web"
+
+STRICT=0
+[[ "${1:-}" == "--strict" ]] && STRICT=1
+
+# Count <label tags WITHOUT htmlFor= on the same line in production
+# tsx (excludes tests + node_modules + dist).
+COUNT_UNBOUND=$(
+  grep -rohE '<label[^>]*>' src \
+    --include='*.tsx' \
+    --exclude='*.test.*' \
+    --exclude-dir='__tests__' \
+    --exclude-dir='node_modules' \
+    --exclude-dir='dist' \
+    2>/dev/null \
+    | grep -vcE 'htmlFor='
+) || true
+
+BASELINE=0
+if [[ -f "$BASELINE_FILE" ]]; then
+  BASELINE=$(cat "$BASELINE_FILE" | tr -d '[:space:]')
+fi
+
+echo "Unbound <label> tags in web/src — current: $COUNT_UNBOUND, baseline: $BASELINE"
+
+if [[ $STRICT -eq 1 ]]; then
+  if [[ $COUNT_UNBOUND -gt 0 ]]; then
+    echo "FAIL (--strict): $COUNT_UNBOUND unbound <label> tag(s) remain. Migrate to <FormField> or add htmlFor=."
+    exit 1
+  fi
+  echo "PASS (--strict): zero unbound <label> tags."
+  exit 0
+fi
+
+if [[ $COUNT_UNBOUND -gt $BASELINE ]]; then
+  echo ""
+  echo "FAIL: A new unbound <label> tag was added ($COUNT_UNBOUND > baseline $BASELINE)."
+  echo ""
+  echo "Wrap the new label in <FormField label='…'>{<input … />}</FormField> — the"
+  echo "primitive at web/src/components/FormField.tsx auto-pairs label htmlFor with"
+  echo "the child input's id via React's useId() so WCAG 1.3.1 holds by construction."
+  echo ""
+  echo "If a raw <label> is genuinely needed (rare: e.g. wrapping a Headless UI"
+  echo "Switch where Headless UI handles the binding internally), add htmlFor=…"
+  echo "explicitly. Then update the baseline:"
+  echo ""
+  echo "  echo $COUNT_UNBOUND > $BASELINE_FILE"
+  echo ""
+  exit 1
+fi
+
+if [[ $COUNT_UNBOUND -lt $BASELINE ]]; then
+  echo ""
+  echo "PASS — and you're under baseline! Drop the baseline to lock in progress:"
+  echo "  echo $COUNT_UNBOUND > $BASELINE_FILE"
+  echo ""
+fi
+
+exit 0
diff --git a/web/package-lock.json b/web/package-lock.json
index fd8d670..b57c2f7 100644
--- a/web/package-lock.json
+++ b/web/package-lock.json
@@ -12,23 +12,29 @@
         "@fontsource-variable/inter": "^5.2.8",
         "@fontsource/jetbrains-mono": "^5.2.8",
         "@headlessui/react": "^2.2.10",
+        "@hookform/resolvers": "^5.2.2",
         "@tanstack/react-query": "^5.90.21",
         "cmdk": "^1.1.1",
         "lucide-react": "^1.16.0",
         "react": "^18.3.1",
         "react-dom": "^18.3.1",
+        "react-hook-form": "^7.75.0",
         "react-router-dom": "^6.30.3",
         "recharts": "^3.8.0",
-        "sonner": "^2.0.7"
+        "sonner": "^2.0.7",
+        "zod": "^4.4.3"
       },
       "devDependencies": {
+        "@axe-core/react": "^4.11.3",
         "@playwright/test": "^1.49.0",
         "@testing-library/jest-dom": "^6.9.1",
         "@testing-library/react": "^16.3.2",
+        "@types/jest-axe": "^3.5.9",
         "@types/react": "^19.2.14",
         "@types/react-dom": "^19.2.3",
         "@vitejs/plugin-react": "^6.0.1",
         "autoprefixer": "^10.4.27",
+        "jest-axe": "^10.0.0",
         "jsdom": "^29.0.0",
         "orval": "^7.0.0",
         "postcss": "^8.5.8",
@@ -161,13 +167,23 @@
         "@types/json-schema": "^7.0.11"
       }
     },
+    "node_modules/@axe-core/react": {
+      "version": "4.11.3",
+      "resolved": "https://registry.npmjs.org/@axe-core/react/-/react-4.11.3.tgz",
+      "integrity": "sha512-G7TrxptKNFfrQZ+Iygb8nGx5w8Su0jIjwmtVN/9Jc4G6RumCh1rD3pZRT2NzZKjT70q4BReuWVwEazS3HxFfjg==",
+      "dev": true,
+      "license": "MPL-2.0",
+      "dependencies": {
+        "axe-core": "~4.11.4",
+        "requestidlecallback": "^0.3.0"
+      }
+    },
     "node_modules/@babel/code-frame": {
       "version": "7.29.0",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.29.0.tgz",
       "integrity": "sha512-9NhCeYjq9+3uxgdtp20LSiJXJvN0FeCtNGpJxuMFZ1Kv3cWUNb6DOhJwUvcVCzKGR66cw4njwM6hrJLqgOwbcw==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "@babel/helper-validator-identifier": "^7.28.5",
         "js-tokens": "^4.0.0",
@@ -183,7 +199,6 @@
       "integrity": "sha512-qSs4ifwzKJSV39ucNjsvc6WVHs6b7S03sOh2OcHF9UHfVPqWWALUsNUVzhSBiItjRZoLHx7nIarVjqKVusUZ1Q==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "engines": {
         "node": ">=6.9.0"
       }
@@ -998,6 +1013,18 @@
         "react-dom": ">=16.8.0"
       }
     },
+    "node_modules/@hookform/resolvers": {
+      "version": "5.2.2",
+      "resolved": "https://registry.npmjs.org/@hookform/resolvers/-/resolvers-5.2.2.tgz",
+      "integrity": "sha512-A/IxlMLShx3KjV/HeTcTfaMxdwy690+L/ZADoeaTltLx+CVuzkeVIPuybK3jrRfw7YZnmdKsVVHAlEPIAEUNlA==",
+      "license": "MIT",
+      "dependencies": {
+        "@standard-schema/utils": "^0.3.0"
+      },
+      "peerDependencies": {
+        "react-hook-form": "^7.55.0"
+      }
+    },
     "node_modules/@ibm-cloud/openapi-ruleset": {
       "version": "1.33.9",
       "resolved": "https://registry.npmjs.org/@ibm-cloud/openapi-ruleset/-/openapi-ruleset-1.33.9.tgz",
@@ -1059,6 +1086,85 @@
         "@swc/helpers": "^0.5.0"
       }
     },
+    "node_modules/@jest/diff-sequences": {
+      "version": "30.4.0",
+      "resolved": "https://registry.npmjs.org/@jest/diff-sequences/-/diff-sequences-30.4.0.tgz",
+      "integrity": "sha512-zOpzlfUs45l6u7jm39qr87JCHUDsaeCtvL+kQe/Vn9jSnRB4/5IPXISm0h9I1vZW/o00Kn4UTJ2MOlhnUGwv3g==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/expect-utils": {
+      "version": "30.4.1",
+      "resolved": "https://registry.npmjs.org/@jest/expect-utils/-/expect-utils-30.4.1.tgz",
+      "integrity": "sha512-ZBn5CglH8fBsQsvs4VWNzD4aWfUYks+IdOOQU3MEK71ol/BcVm+P+rtb1KpiFBpSWSCE27uOahyyf1vfqOVbcQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/get-type": "30.1.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/get-type": {
+      "version": "30.1.0",
+      "resolved": "https://registry.npmjs.org/@jest/get-type/-/get-type-30.1.0.tgz",
+      "integrity": "sha512-eMbZE2hUnx1WV0pmURZY9XoXPkUYjpc55mb0CrhtdWLtzMQPFvu/rZkTLZFTsdaVQa+Tr4eWAteqcUzoawq/uA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/pattern": {
+      "version": "30.4.0",
+      "resolved": "https://registry.npmjs.org/@jest/pattern/-/pattern-30.4.0.tgz",
+      "integrity": "sha512-RAWn3+f9u8BsHijKJ71uHcFp6vmyEt6VvoWXkl6hKF3qVIuWNmudVjg12DlBPGup/frIl5UcUlH5HfEuvHpEXg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*",
+        "jest-regex-util": "30.4.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/schemas": {
+      "version": "30.4.1",
+      "resolved": "https://registry.npmjs.org/@jest/schemas/-/schemas-30.4.1.tgz",
+      "integrity": "sha512-i6b4qw5qnP8c5FEeBJg/uZQ4ddrkN6Ca8qISJh0pr7a5hfn3h3v5x60BEbOC7OYAGZNMs1LfFLwnW2CuK8F57Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@sinclair/typebox": "^0.34.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/types": {
+      "version": "30.4.1",
+      "resolved": "https://registry.npmjs.org/@jest/types/-/types-30.4.1.tgz",
+      "integrity": "sha512-f1x/vJXIfjOlEmejYpbkbgw1gOqpPECwMvMEtBqe47j7H2Hg8h8w3o3ikhSXq3MI15kg+oQ0exWO0uCtTNJLoQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/pattern": "30.4.0",
+        "@jest/schemas": "30.4.1",
+        "@types/istanbul-lib-coverage": "^2.0.6",
+        "@types/istanbul-reports": "^3.0.4",
+        "@types/node": "*",
+        "@types/yargs": "^17.0.33",
+        "chalk": "^4.1.2"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
     "node_modules/@jridgewell/gen-mapping": {
       "version": "0.3.13",
       "resolved": "https://registry.npmjs.org/@jridgewell/gen-mapping/-/gen-mapping-0.3.13.tgz",
@@ -2674,6 +2780,13 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/@sinclair/typebox": {
+      "version": "0.34.49",
+      "resolved": "https://registry.npmjs.org/@sinclair/typebox/-/typebox-0.34.49.tgz",
+      "integrity": "sha512-brySQQs7Jtn0joV8Xh9ZV/hZb9Ozb0pmazDIASBkYKCjXrXU3mpcFahmK/z4YDhGkQvP9mWJbVyahdtU5wQA+A==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@standard-schema/spec": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/@standard-schema/spec/-/spec-1.1.0.tgz",
@@ -3307,6 +3420,81 @@
         "@types/unist": "*"
       }
     },
+    "node_modules/@types/istanbul-lib-coverage": {
+      "version": "2.0.6",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-lib-coverage/-/istanbul-lib-coverage-2.0.6.tgz",
+      "integrity": "sha512-2QF/t/auWm0lsy8XtKVPG19v3sSOQlJe/YHZgfjb/KBBHOGSV+J2q/S671rcq9uTBrLAXmZpqJiaQbMT+zNU1w==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/istanbul-lib-report": {
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-lib-report/-/istanbul-lib-report-3.0.3.tgz",
+      "integrity": "sha512-NQn7AHQnk/RSLOxrBbGyJM/aVQ+pjj5HCgasFxc0K/KhoATfQ/47AyUl15I2yBUpihjmas+a+VJBOqecrFH+uA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/istanbul-lib-coverage": "*"
+      }
+    },
+    "node_modules/@types/istanbul-reports": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/@types/istanbul-reports/-/istanbul-reports-3.0.4.tgz",
+      "integrity": "sha512-pk2B1NWalF9toCRu6gjBzR69syFjP4Od8WRAX+0mmf9lAjCRicLOWc+ZrxZHx/0XRjotgkF9t6iaMJ+aXcOdZQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/istanbul-lib-report": "*"
+      }
+    },
+    "node_modules/@types/jest": {
+      "version": "30.0.0",
+      "resolved": "https://registry.npmjs.org/@types/jest/-/jest-30.0.0.tgz",
+      "integrity": "sha512-XTYugzhuwqWjws0CVz8QpM36+T+Dz5mTEBKhNs/esGLnCIlGdRy+Dq78NRjd7ls7r8BC8ZRMOrKlkO1hU0JOwA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "expect": "^30.0.0",
+        "pretty-format": "^30.0.0"
+      }
+    },
+    "node_modules/@types/jest-axe": {
+      "version": "3.5.9",
+      "resolved": "https://registry.npmjs.org/@types/jest-axe/-/jest-axe-3.5.9.tgz",
+      "integrity": "sha512-z98CzR0yVDalCEuhGXXO4/zN4HHuSebAukXDjTLJyjEAgoUf1H1i+sr7SUB/mz8CRS/03/XChsx0dcLjHkndoQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/jest": "*",
+        "axe-core": "^3.5.5"
+      }
+    },
+    "node_modules/@types/jest-axe/node_modules/axe-core": {
+      "version": "3.5.6",
+      "resolved": "https://registry.npmjs.org/axe-core/-/axe-core-3.5.6.tgz",
+      "integrity": "sha512-LEUDjgmdJoA3LqklSTwKYqkjcZ4HKc4ddIYGSAiSkr46NTjzg2L9RNB+lekO9P7Dlpa87+hBtzc2Fzn/+GUWMQ==",
+      "dev": true,
+      "license": "MPL-2.0",
+      "engines": {
+        "node": ">=4"
+      }
+    },
+    "node_modules/@types/jest/node_modules/pretty-format": {
+      "version": "30.4.1",
+      "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-30.4.1.tgz",
+      "integrity": "sha512-K6KiKMHTL4jjX4u3Kir2EW07nRfcqVTXIImx50wbjHQTcZPgg+gjVeNTIT3l3L1Rd4UefxfogquC9J37SoFyyw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/schemas": "30.4.1",
+        "ansi-styles": "^5.2.0",
+        "react-is-18": "npm:react-is@^18.3.1",
+        "react-is-19": "npm:react-is@^19.2.5"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
     "node_modules/@types/json-schema": {
       "version": "7.0.15",
       "resolved": "https://registry.npmjs.org/@types/json-schema/-/json-schema-7.0.15.tgz",
@@ -3344,6 +3532,13 @@
         "@types/react": "^19.2.0"
       }
     },
+    "node_modules/@types/stack-utils": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/@types/stack-utils/-/stack-utils-2.0.3.tgz",
+      "integrity": "sha512-9aEbYZ3TbYMznPdcdr3SmIrLXwC/AKZXQeCf9Pgao5CKb8CyHuEX5jzWPTkvregvhRJHcpRO6BFoGW9ycaOkYw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@types/unist": {
       "version": "3.0.3",
       "resolved": "https://registry.npmjs.org/@types/unist/-/unist-3.0.3.tgz",
@@ -3364,6 +3559,23 @@
       "integrity": "sha512-zFDAD+tlpf2r4asuHEj0XH6pY6i0g5NeAHPn+15wk3BV6JA69eERFXC1gyGThDkVa1zCyKr5jox1+2LbV/AMLg==",
       "license": "MIT"
     },
+    "node_modules/@types/yargs": {
+      "version": "17.0.35",
+      "resolved": "https://registry.npmjs.org/@types/yargs/-/yargs-17.0.35.tgz",
+      "integrity": "sha512-qUHkeCyQFxMXg79wQfTtfndEC+N9ZZg76HJftDJp+qH2tV7Gj4OJi7l+PiWwJ+pWtW8GwSmqsDj/oymhrTWXjg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/yargs-parser": "*"
+      }
+    },
+    "node_modules/@types/yargs-parser": {
+      "version": "21.0.3",
+      "resolved": "https://registry.npmjs.org/@types/yargs-parser/-/yargs-parser-21.0.3.tgz",
+      "integrity": "sha512-I4q9QU9MQv4oEOz4tAHJtNz1cwuLxn2F3xcc2iV5WdqLPpUnj30aUuxt1mAxYTG+oe8CZMV/+6rU4S4gRDzqtQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@vitejs/plugin-react": {
       "version": "6.0.1",
       "resolved": "https://registry.npmjs.org/@vitejs/plugin-react/-/plugin-react-6.0.1.tgz",
@@ -3615,7 +3827,6 @@
       "integrity": "sha512-Cxwpt2SfTzTtXcfOlzGEee8O+c+MmUgGrNiBcXnuWxuFJHe6a5Hz7qwhwe5OgaSYI0IJvkLqWX1ASG+cJOkEiA==",
       "dev": true,
       "license": "MIT",
-      "peer": true,
       "engines": {
         "node": ">=10"
       },
@@ -3812,6 +4023,16 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/axe-core": {
+      "version": "4.11.4",
+      "resolved": "https://registry.npmjs.org/axe-core/-/axe-core-4.11.4.tgz",
+      "integrity": "sha512-KunSNx+TVpkAw/6ULfhnx+HWRecjqZGTOyquAoWHYLRSdK1tB5Ihce1ZW+UY3fj33bYAFWPu7W/GRSmmrCGuxA==",
+      "dev": true,
+      "license": "MPL-2.0",
+      "engines": {
+        "node": ">=4"
+      }
+    },
     "node_modules/balanced-match": {
       "version": "4.0.4",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-4.0.4.tgz",
@@ -4087,6 +4308,22 @@
         "node": ">= 6"
       }
     },
+    "node_modules/ci-info": {
+      "version": "4.4.0",
+      "resolved": "https://registry.npmjs.org/ci-info/-/ci-info-4.4.0.tgz",
+      "integrity": "sha512-77PSwercCZU2Fc4sX94eF8k8Pxte6JAwL4/ICZLFjJLqegs7kCuAsqqj/70NQF6TvDpgFjkubQB2FW2ZZddvQg==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/sibiraj-s"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
+    },
     "node_modules/cliui": {
       "version": "8.0.1",
       "resolved": "https://registry.npmjs.org/cliui/-/cliui-8.0.1.tgz",
@@ -4533,6 +4770,16 @@
       "dev": true,
       "license": "Apache-2.0"
     },
+    "node_modules/diff-sequences": {
+      "version": "29.6.3",
+      "resolved": "https://registry.npmjs.org/diff-sequences/-/diff-sequences-29.6.3.tgz",
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+      "license": "MIT",
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+      "version": "30.4.1",
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+      "license": "MIT",
+      "dependencies": {
+        "@jest/types": "30.4.1",
+        "@types/node": "*",
+        "chalk": "^4.1.2",
+        "ci-info": "^4.2.0",
+        "graceful-fs": "^4.2.11",
+        "picomatch": "^4.0.3"
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+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
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+    },
     "node_modules/jiti": {
       "version": "1.21.7",
       "resolved": "https://registry.npmjs.org/jiti/-/jiti-1.21.7.tgz",
@@ -6424,6 +6954,13 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/lodash.merge": {
+      "version": "4.6.2",
+      "resolved": "https://registry.npmjs.org/lodash.merge/-/lodash.merge-4.6.2.tgz",
+      "integrity": "sha512-0KpjqXRVvrYyCsX1swR/XTK0va6VQkQM6MNo7PqW77ByjAhoARA8EfrP1N4+KlKj8YS0ZUCtRT/YUuhyYDujIQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/lodash.omitby": {
       "version": "4.6.0",
       "resolved": "https://registry.npmjs.org/lodash.omitby/-/lodash.omitby-4.6.0.tgz",
@@ -7615,6 +8152,22 @@
         "react": "^18.3.1"
       }
     },
+    "node_modules/react-hook-form": {
+      "version": "7.75.0",
+      "resolved": "https://registry.npmjs.org/react-hook-form/-/react-hook-form-7.75.0.tgz",
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+      "license": "MIT",
+      "engines": {
+        "node": ">=18.0.0"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/react-hook-form"
+      },
+      "peerDependencies": {
+        "react": "^16.8.0 || ^17 || ^18 || ^19"
+      }
+    },
     "node_modules/react-is": {
       "version": "17.0.2",
       "resolved": "https://registry.npmjs.org/react-is/-/react-is-17.0.2.tgz",
@@ -7622,6 +8175,22 @@
       "license": "MIT",
       "peer": true
     },
+    "node_modules/react-is-18": {
+      "name": "react-is",
+      "version": "18.3.1",
+      "resolved": "https://registry.npmjs.org/react-is/-/react-is-18.3.1.tgz",
+      "integrity": "sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/react-is-19": {
+      "name": "react-is",
+      "version": "19.2.6",
+      "resolved": "https://registry.npmjs.org/react-is/-/react-is-19.2.6.tgz",
+      "integrity": "sha512-XjBR15BhXuylgWGuslhDKqlSayuqvqBX91BP8pauG8kd1zY8kotkNWbXksTCNRarse4kuGbe2kIY05ARtwNIvw==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/react-redux": {
       "version": "9.2.0",
       "resolved": "https://registry.npmjs.org/react-redux/-/react-redux-9.2.0.tgz",
@@ -7899,6 +8468,13 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/requestidlecallback": {
+      "version": "0.3.0",
+      "resolved": "https://registry.npmjs.org/requestidlecallback/-/requestidlecallback-0.3.0.tgz",
+      "integrity": "sha512-TWHFkT7S9p7IxLC5A1hYmAYQx2Eb9w1skrXmQ+dS1URyvR8tenMLl4lHbqEOUnpEYxNKpkVMXUgknVpBZWXXfQ==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/require-directory": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/require-directory/-/require-directory-2.1.1.tgz",
@@ -8358,6 +8934,19 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/stack-utils": {
+      "version": "2.0.6",
+      "resolved": "https://registry.npmjs.org/stack-utils/-/stack-utils-2.0.6.tgz",
+      "integrity": "sha512-XlkWvfIm6RmsWtNJx+uqtKLS8eqFbxUg0ZzLXqY0caEy9l7hruX8IpiDnjsLavoBgqCCR71TqWO8MaXYheJ3RQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "escape-string-regexp": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=10"
+      }
+    },
     "node_modules/stackback": {
       "version": "0.0.2",
       "resolved": "https://registry.npmjs.org/stackback/-/stackback-0.0.2.tgz",
@@ -9626,6 +10215,15 @@
       "funding": {
         "url": "https://github.com/sponsors/sindresorhus"
       }
+    },
+    "node_modules/zod": {
+      "version": "4.4.3",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-4.4.3.tgz",
+      "integrity": "sha512-ytENFjIJFl2UwYglde2jchW2Hwm4GJFLDiSXWdTrJQBIN9Fcyp7n4DhxJEiWNAJMV1/BqWfW/kkg71UDcHJyTQ==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
     }
   }
 }
diff --git a/web/package.json b/web/package.json
index 345a55f..2856b35 100644
--- a/web/package.json
+++ b/web/package.json
@@ -18,23 +18,29 @@
     "@fontsource-variable/inter": "^5.2.8",
     "@fontsource/jetbrains-mono": "^5.2.8",
     "@headlessui/react": "^2.2.10",
+    "@hookform/resolvers": "^5.2.2",
     "@tanstack/react-query": "^5.90.21",
     "cmdk": "^1.1.1",
     "lucide-react": "^1.16.0",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
+    "react-hook-form": "^7.75.0",
     "react-router-dom": "^6.30.3",
     "recharts": "^3.8.0",
-    "sonner": "^2.0.7"
+    "sonner": "^2.0.7",
+    "zod": "^4.4.3"
   },
   "devDependencies": {
+    "@axe-core/react": "^4.11.3",
     "@playwright/test": "^1.49.0",
     "@testing-library/jest-dom": "^6.9.1",
     "@testing-library/react": "^16.3.2",
+    "@types/jest-axe": "^3.5.9",
     "@types/react": "^19.2.14",
     "@types/react-dom": "^19.2.3",
     "@vitejs/plugin-react": "^6.0.1",
     "autoprefixer": "^10.4.27",
+    "jest-axe": "^10.0.0",
     "jsdom": "^29.0.0",
     "orval": "^7.0.0",
     "postcss": "^8.5.8",
diff --git a/web/src/components/FormField.test.tsx b/web/src/components/FormField.test.tsx
new file mode 100644
index 0000000..5e19c7b
--- /dev/null
+++ b/web/src/components/FormField.test.tsx
@@ -0,0 +1,112 @@
+import { describe, it, expect } from 'vitest';
+import { render, screen, fireEvent } from '@testing-library/react';
+import { useForm } from 'react-hook-form';
+import FormField from './FormField';
+
+describe('FormField', () => {
+  it('label htmlFor matches input id (the WCAG 1.3.1 contract)', () => {
+    render(
+      <FormField label="Email">
+        <input type="email" />
+      </FormField>,
+    );
+    const label = screen.getByText('Email');
+    const input = screen.getByLabelText('Email');
+    // Programmatic label association — what screen readers use.
+    expect(input).toBeInTheDocument();
+    expect(label).toHaveAttribute('for', input.id);
+    // useId() gives a non-empty id by definition.
+    expect(input.id).toMatch(/^field-/);
+  });
+
+  it('two siblings get independent ids (no collision)', () => {
+    render(
+      <>
+        <FormField label="Name"><input /></FormField>
+        <FormField label="Description"><input /></FormField>
+      </>,
+    );
+    const a = screen.getByLabelText('Name');
+    const b = screen.getByLabelText('Description');
+    expect(a.id).not.toBe(b.id);
+  });
+
+  it('required surfaces the asterisk + aria-required on the child', () => {
+    render(
+      <FormField label="Email" required>
+        <input type="email" />
+      </FormField>,
+    );
+    expect(screen.getByText('*')).toBeInTheDocument();
+    expect(screen.getByLabelText(/Email/)).toHaveAttribute('aria-required', 'true');
+  });
+
+  it('description wires aria-describedby to the child', () => {
+    render(
+      <FormField label="Token" description="Paste the API key from /auth/keys">
+        <input />
+      </FormField>,
+    );
+    const input = screen.getByLabelText('Token');
+    const desc = screen.getByText(/Paste the API key/);
+    expect(input.getAttribute('aria-describedby')).toContain(desc.id);
+  });
+
+  it('error sets aria-invalid + role=alert + extends aria-describedby', () => {
+    render(
+      <FormField label="Email" error="Must be a valid email address">
+        <input type="email" />
+      </FormField>,
+    );
+    const input = screen.getByLabelText('Email');
+    expect(input).toHaveAttribute('aria-invalid', 'true');
+    const err = screen.getByRole('alert');
+    expect(err).toHaveTextContent('Must be a valid email address');
+    expect(input.getAttribute('aria-describedby')).toContain(err.id);
+  });
+
+  it('composes cleanly with react-hook-form register() — spread + clone preserves both', () => {
+    function Form({ onSubmit }: { onSubmit: (v: { name: string }) => void }) {
+      const { register, handleSubmit } = useForm<{ name: string }>();
+      return (
+        <form onSubmit={handleSubmit(onSubmit)}>
+          <FormField label="Name">
+            <input {...register('name')} />
+          </FormField>
+          <button type="submit">Save</button>
+        </form>
+      );
+    }
+    let captured = '';
+    render(<Form onSubmit={(v) => { captured = v.name; }} />);
+    const input = screen.getByLabelText('Name');
+    fireEvent.change(input, { target: { value: 'alice' } });
+    fireEvent.click(screen.getByText('Save'));
+    return new Promise<void>((resolve) => {
+      setTimeout(() => {
+        expect(captured).toBe('alice');
+        // Both RHF's name and FormField's id co-exist.
+        expect(input.getAttribute('name')).toBe('name');
+        expect(input.id).toMatch(/^field-/);
+        resolve();
+      }, 10);
+    });
+  });
+
+  it('throws clearly when child is not a single valid element', () => {
+    // Suppress React's error-boundary console spam for this assertion.
+    const orig = console.error;
+    console.error = () => {};
+    try {
+      expect(() =>
+        render(
+          <FormField label="Bad">
+            {'plain string is not valid'}
+          </FormField>,
+        ),
+      ).toThrow();
+    } finally {
+      console.error = orig;
+    }
+  });
+});
diff --git a/web/src/components/FormField.tsx b/web/src/components/FormField.tsx
new file mode 100644
index 0000000..dbfb4ea
--- /dev/null
+++ b/web/src/components/FormField.tsx
@@ -0,0 +1,118 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// FormField — Phase 5 closure for UX-H4 + the foundation of FE-M1.
+//
+// Pre-Phase-5 state: 139 <label> elements in production tsx; 6 with
+// htmlFor; 0 inputs with id. WCAG 1.3.1 (info-and-relationships) fails
+// on ~99% of form fields — screen readers can't programmatically pair
+// a label with its input, so "Email" reads as a floating string rather
+// than as the accessible name of the adjacent input.
+//
+// FormField fixes this by generating a stable id with React 18's
+// useId() and threading it to BOTH the <label htmlFor=...> AND the
+// child input's id prop via cloneElement. Consumers write:
+//
+//   <FormField label="Email" required>
+//     <input type="email" value={email} onChange={…} />
+//   </FormField>
+//
+// — no manual id wiring, no risk of id-mismatch drift, no chance a
+// developer copies the JSX and forgets to update one of the two
+// strings. The label-↔-input binding is correct by construction.
+//
+// Composition with react-hook-form is straight-forward — RHF's
+// register('field') returns onChange/onBlur/ref/name which spread onto
+// the input alongside FormField's auto-id. The Zod-resolver path picks
+// up errors and FormField surfaces them via the `error` prop slot.
+
+import { Children, cloneElement, isValidElement, useId } from 'react';
+import type { ReactElement, ReactNode } from 'react';
+
+interface FormFieldProps {
+  /** Visible label text. Required for a11y — never render an unbound input. */
+  label: string;
+  /** Render `*` next to the label when true (display-only; validation lives in Zod). */
+  required?: boolean;
+  /** Optional helper / description text below the input. */
+  description?: string;
+  /** Optional error message — when set, surfaces below the input + flags aria-invalid. */
+  error?: string;
+  /** Optional class override for the wrapping div. */
+  className?: string;
+  /**
+   * Exactly one input-shaped child (<input>, <select>, <textarea>, or any
+   * forwardRef'd component that accepts `id` + `aria-describedby` +
+   * `aria-invalid` as props). FormField clones it and injects the
+   * auto-generated id so the label-↔-input pairing is correct by
+   * construction.
+   */
+  children: ReactNode;
+}
+
+export default function FormField({
+  label,
+  required,
+  description,
+  error,
+  className,
+  children,
+}: FormFieldProps) {
+  // useId() returns a stable id that's unique per render-tree-position,
+  // safe under StrictMode, and SSR-friendly. Two siblings get different
+  // ids automatically.
+  const reactId = useId();
+  const inputId = `field-${reactId}`;
+  const descId = description ? `desc-${reactId}` : undefined;
+  const errorId = error ? `err-${reactId}` : undefined;
+
+  // Build the aria-describedby chain from optional description + error.
+  // Browsers concatenate space-separated ids, so screen readers announce
+  // "Email, [description], [error]".
+  const describedBy = [descId, errorId].filter(Boolean).join(' ') || undefined;
+
+  const onlyChild = Children.only(children);
+  if (!isValidElement(onlyChild)) {
+    // Surface a clear error in dev rather than render a broken control.
+    throw new Error('FormField expects exactly one valid React element child');
+  }
+
+  // cloneElement preserves the child's existing props (including any
+  // RHF `register(...)` spread) and overlays the FormField-managed
+  // a11y props on top. The child's `id` / `aria-*` are always set
+  // here, but `name`/`value`/`onChange` from the child are preserved.
+  const childWithA11y = cloneElement(
+    onlyChild as ReactElement<Record<string, unknown>>,
+    {
+      id: inputId,
+      'aria-describedby': describedBy,
+      'aria-invalid': error ? true : undefined,
+      'aria-required': required ? true : undefined,
+    },
+  );
+
+  return (
+    <div className={className ?? 'mb-4'}>
+      <label
+        htmlFor={inputId}
+        className="block text-sm font-medium text-ink mb-1.5"
+      >
+        {label}
+        {required && (
+          <span className="text-red-600 ml-0.5" aria-hidden="true">*</span>
+        )}
+      </label>
+      {childWithA11y}
+      {description && (
+        <p id={descId} className="mt-1 text-xs text-ink-muted">
+          {description}
+        </p>
+      )}
+      {error && (
+        <p id={errorId} role="alert" className="mt-1 text-xs text-red-700">
+          {error}
+        </p>
+      )}
+    </div>
+  );
+}
diff --git a/web/src/components/ModalDialog.test.tsx b/web/src/components/ModalDialog.test.tsx
new file mode 100644
index 0000000..eee2822
--- /dev/null
+++ b/web/src/components/ModalDialog.test.tsx
@@ -0,0 +1,73 @@
+import { describe, it, expect, vi } from 'vitest';
+import { render, screen, fireEvent } from '@testing-library/react';
+import ModalDialog from './ModalDialog';
+
+describe('ModalDialog', () => {
+  it('renders nothing when open=false', () => {
+    render(
+      <ModalDialog open={false} title="Hidden" onClose={() => {}}>
+        body content
+      </ModalDialog>,
+    );
+    expect(screen.queryByText('Hidden')).toBeNull();
+    expect(screen.queryByText('body content')).toBeNull();
+  });
+
+  it('renders title + children when open', () => {
+    render(
+      <ModalDialog open={true} title="Confirm thing" onClose={() => {}}>
+        <p>This is the body</p>
+      </ModalDialog>,
+    );
+    expect(screen.getByText('Confirm thing')).toBeInTheDocument();
+    expect(screen.getByText('This is the body')).toBeInTheDocument();
+  });
+
+  it('Headless UI sets role=dialog + aria-modal on the panel', () => {
+    render(
+      <ModalDialog open={true} title="t" onClose={() => {}}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    const dialog = screen.getByRole('dialog');
+    expect(dialog).toHaveAttribute('aria-modal', 'true');
+  });
+
+  it('title acts as aria-labelledby target', () => {
+    render(
+      <ModalDialog open={true} title="Pin me" onClose={() => {}}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    const dialog = screen.getByRole('dialog');
+    const labelId = dialog.getAttribute('aria-labelledby');
+    expect(labelId).toBeTruthy();
+    const labelEl = document.getElementById(labelId!);
+    expect(labelEl).toHaveTextContent('Pin me');
+  });
+
+  it('ESC key fires onClose', () => {
+    const onClose = vi.fn();
+    render(
+      <ModalDialog open={true} title="x" onClose={onClose}>
+        <span>body</span>
+      </ModalDialog>,
+    );
+    fireEvent.keyDown(document, { key: 'Escape' });
+    expect(onClose).toHaveBeenCalled();
+  });
+
+  it('footer renders separately when provided', () => {
+    render(
+      <ModalDialog
+        open={true}
+        title="x"
+        onClose={() => {}}
+        footer={<button>OK</button>}
+      >
+        body
+      </ModalDialog>,
+    );
+    expect(screen.getByRole('button', { name: 'OK' })).toBeInTheDocument();
+  });
+});
diff --git a/web/src/components/ModalDialog.tsx b/web/src/components/ModalDialog.tsx
new file mode 100644
index 0000000..ee513f2
--- /dev/null
+++ b/web/src/components/ModalDialog.tsx
@@ -0,0 +1,119 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// ModalDialog — Phase 5 closure for FE-H3 (3 inline-managed modal
+// pages — SCEPAdminPage, AgentsPage, ESTAdminPage — set
+// role="dialog" + aria-modal="true" + aria-labelledby but no focus
+// trap, no ESC-to-close, no backdrop-click-to-close).
+//
+// Built on Headless UI's <Dialog>, identical pattern to ConfirmDialog
+// (Phase 1) but accepts arbitrary <ModalDialog.Body> content rather
+// than the constrained confirm/cancel button pair ConfirmDialog
+// provides. Use ConfirmDialog for "click YES to do destructive thing";
+// use ModalDialog for "modal that contains a form / multi-action
+// content / a status display".
+//
+// What Headless UI gives us for free (same as ConfirmDialog):
+//   • automatic focus trap (Tab/Shift-Tab stays inside the dialog)
+//   • automatic ESC-to-close → onClose() callback
+//   • automatic backdrop-click-to-close → onClose() callback
+//   • role="dialog" + aria-modal="true" on the panel
+//   • aria-labelledby on the title node
+//   • <Transition> respects prefers-reduced-motion via the global
+//     @media block in src/index.css
+//
+// FE-H3 closure scope: the 3 inline-managed modal sites all get
+// migrated to this primitive in the same commit. ConfirmDialog stays
+// as-is for confirm-only flows it already serves.
+
+import { Fragment } from 'react';
+import type { ReactNode } from 'react';
+import { Dialog, Transition } from '@headlessui/react';
+
+export interface ModalDialogProps {
+  /** Controls visibility. Parent owns the boolean. */
+  open: boolean;
+  /** Title shown at the top — also acts as aria-labelledby target. */
+  title: string;
+  /** Fires on ESC, backdrop click, or external close trigger. */
+  onClose: () => void;
+  /**
+   * Dialog body — render the form, status, or multi-action content here.
+   * The body is wrapped in the styled panel; consumers don't need to
+   * wrap their content in another <div>.
+   */
+  children: ReactNode;
+  /**
+   * Footer slot for action buttons. Optional — some modals (e.g. error
+   * displays) only show a "Close" affordance which can live inside
+   * children. When provided, footer is separated by a top border.
+   */
+  footer?: ReactNode;
+  /** Maximum width — defaults to `max-w-md` (matches ConfirmDialog). */
+  maxWidth?: 'sm' | 'md' | 'lg' | 'xl' | '2xl';
+}
+
+const maxWidthMap = {
+  sm:  'max-w-sm',
+  md:  'max-w-md',
+  lg:  'max-w-lg',
+  xl:  'max-w-xl',
+  '2xl': 'max-w-2xl',
+} as const;
+
+export default function ModalDialog({
+  open,
+  title,
+  onClose,
+  children,
+  footer,
+  maxWidth = 'md',
+}: ModalDialogProps) {
+  return (
+    <Transition show={open} as={Fragment}>
+      <Dialog onClose={onClose} className="relative z-50">
+        {/* Backdrop. Headless UI wires backdrop-click → onClose. */}
+        <Transition.Child
+          as={Fragment}
+          enter="ease-out duration-200"
+          enterFrom="opacity-0"
+          enterTo="opacity-100"
+          leave="ease-in duration-150"
+          leaveFrom="opacity-100"
+          leaveTo="opacity-0"
+        >
+          <div className="fixed inset-0 bg-black/40" aria-hidden="true" />
+        </Transition.Child>
+
+        {/* Panel container. */}
+        <div className="fixed inset-0 flex items-center justify-center p-4">
+          <Transition.Child
+            as={Fragment}
+            enter="ease-out duration-200"
+            enterFrom="opacity-0 scale-95"
+            enterTo="opacity-100 scale-100"
+            leave="ease-in duration-150"
+            leaveFrom="opacity-100 scale-100"
+            leaveTo="opacity-0 scale-95"
+          >
+            <Dialog.Panel
+              className={`bg-surface w-full ${maxWidthMap[maxWidth]} rounded-lg shadow-xl border border-surface-border`}
+            >
+              <div className="p-6">
+                <Dialog.Title className="text-base font-semibold text-ink mb-3">
+                  {title}
+                </Dialog.Title>
+                <div className="text-sm text-ink">{children}</div>
+              </div>
+              {footer && (
+                <div className="border-t border-surface-border px-6 py-4 flex justify-end gap-2">
+                  {footer}
+                </div>
+              )}
+            </Dialog.Panel>
+          </Transition.Child>
+        </div>
+      </Dialog>
+    </Transition>
+  );
+}
diff --git a/web/src/pages/AgentsPage.tsx b/web/src/pages/AgentsPage.tsx
index 591733d..7830d43 100644
--- a/web/src/pages/AgentsPage.tsx
+++ b/web/src/pages/AgentsPage.tsx
@@ -9,6 +9,7 @@ import {
   BlockedByDependenciesError,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import DataTable from '../components/DataTable';
 import type { Column } from '../components/DataTable';
 import StatusBadge from '../components/StatusBadge';
@@ -309,129 +310,133 @@ function RetireModal({
 }) {
   if (mode.kind === 'closed') return null;
 
+  // Phase 5 closure (FE-H3): swapped inline `<div role="dialog">` markup
+  // for ModalDialog (Headless UI). Each of the 3 modes (confirm / blocked /
+  // error) renders inside the same dialog shell, so focus trap + ESC + click-
+  // outside come for free. Title + footer change per mode; body is the
+  // mode-specific content.
+  const title =
+    mode.kind === 'confirm' ? 'Retire agent' :
+    mode.kind === 'blocked' ? 'Cannot retire — active dependencies' :
+    /* error */ 'Retire failed';
+
   return (
-    <div
-      role="dialog"
-      aria-modal="true"
-      className="fixed inset-0 z-40 flex items-center justify-center bg-black/40"
-      onClick={onClose}
+    <ModalDialog
+      open={true}
+      title={title}
+      onClose={pending ? () => {} : onClose}
+      maxWidth="lg"
+      footer={
+        mode.kind === 'confirm' ? (
+          <>
+            <button
+              type="button"
+              onClick={onClose}
+              className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+              disabled={pending}
+            >
+              Cancel
+            </button>
+            <button
+              type="button"
+              onClick={onSoftRetire}
+              disabled={pending}
+              className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
+            >
+              {pending ? 'Retiring…' : 'Retire'}
+            </button>
+          </>
+        ) : mode.kind === 'blocked' ? (
+          <>
+            <button
+              type="button"
+              onClick={onClose}
+              className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+              disabled={pending}
+            >
+              Cancel
+            </button>
+            <button
+              type="button"
+              onClick={onForceRetire}
+              // Backend enforces reason on force; keep the GUI in lockstep
+              // rather than letting a 400 bounce back.
+              disabled={pending || !mode.reason.trim()}
+              className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
+            >
+              {pending ? 'Force-retiring…' : 'Force retire'}
+            </button>
+          </>
+        ) : (
+          <button
+            type="button"
+            onClick={onClose}
+            className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
+          >
+            Close
+          </button>
+        )
+      }
     >
-      <div
-        className="w-full max-w-lg rounded-lg bg-surface p-6 shadow-lg border border-border"
-        onClick={(e) => e.stopPropagation()}
-      >
-        {mode.kind === 'confirm' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Retire agent</h2>
-            <p className="mt-2 text-sm text-ink-muted">
-              <span className="font-mono">{mode.agent.name}</span> ({mode.agent.id}) will be
-              soft-retired. The agent will stop receiving heartbeats and be removed from active
-              listings. This is reversible only by direct database intervention.
-            </p>
-            <label className="mt-4 block text-xs font-medium text-ink-muted">
-              Reason (optional)
-              <input
-                type="text"
-                value={mode.reason}
-                onChange={(e) => onReasonChange(e.target.value)}
-                placeholder="e.g. decommissioning rack 7"
-                className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
-              />
-            </label>
-            <div className="mt-6 flex justify-end gap-2">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-                disabled={pending}
-              >
-                Cancel
-              </button>
-              <button
-                type="button"
-                onClick={onSoftRetire}
-                disabled={pending}
-                className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
-              >
-                {pending ? 'Retiring…' : 'Retire'}
-              </button>
-            </div>
-          </>
-        )}
+      {mode.kind === 'confirm' && (
+        <>
+          <p className="text-sm text-ink-muted">
+            <span className="font-mono">{mode.agent.name}</span> ({mode.agent.id}) will be
+            soft-retired. The agent will stop receiving heartbeats and be removed from active
+            listings. This is reversible only by direct database intervention.
+          </p>
+          <label className="mt-4 block text-xs font-medium text-ink-muted">
+            Reason (optional)
+            <input
+              type="text"
+              value={mode.reason}
+              onChange={(e) => onReasonChange(e.target.value)}
+              placeholder="e.g. decommissioning rack 7"
+              className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
+            />
+          </label>
+        </>
+      )}
 
-        {mode.kind === 'blocked' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Cannot retire — active dependencies</h2>
-            <p className="mt-2 text-sm text-ink-muted">
-              The agent <span className="font-mono">{mode.agent.name}</span> still has downstream
-              work tied to it. Force-retiring will cascade-retire all active targets and fail any
-              pending jobs.
-            </p>
-            <dl className="mt-4 grid grid-cols-3 gap-3 text-center">
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Active targets</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.active_targets}</dd>
-              </div>
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Active certs</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">
-                  {mode.counts.active_certificates}
-                </dd>
-              </div>
-              <div className="rounded border border-border bg-surface-alt p-3">
-                <dt className="text-xs text-ink-muted">Pending jobs</dt>
-                <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.pending_jobs}</dd>
-              </div>
-            </dl>
-            <label className="mt-4 block text-xs font-medium text-ink-muted">
-              Reason <span className="text-danger">(required for force retire)</span>
-              <input
-                type="text"
-                value={mode.reason}
-                onChange={(e) => onReasonChange(e.target.value)}
-                placeholder="e.g. rack 7 decommission, cascade retire"
-                className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
-              />
-            </label>
-            <div className="mt-6 flex justify-end gap-2">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-                disabled={pending}
-              >
-                Cancel
-              </button>
-              <button
-                type="button"
-                onClick={onForceRetire}
-                // Backend enforces reason on force; keep the GUI in lockstep
-                // rather than letting a 400 bounce back.
-                disabled={pending || !mode.reason.trim()}
-                className="px-4 py-2 text-sm font-medium text-white bg-danger rounded hover:bg-danger/90 disabled:opacity-50"
-              >
-                {pending ? 'Force-retiring…' : 'Force retire'}
-              </button>
+      {mode.kind === 'blocked' && (
+        <>
+          <p className="text-sm text-ink-muted">
+            The agent <span className="font-mono">{mode.agent.name}</span> still has downstream
+            work tied to it. Force-retiring will cascade-retire all active targets and fail any
+            pending jobs.
+          </p>
+          <dl className="mt-4 grid grid-cols-3 gap-3 text-center">
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Active targets</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.active_targets}</dd>
             </div>
-          </>
-        )}
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Active certs</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">
+                {mode.counts.active_certificates}
+              </dd>
+            </div>
+            <div className="rounded border border-border bg-surface-alt p-3">
+              <dt className="text-xs text-ink-muted">Pending jobs</dt>
+              <dd className="mt-1 text-xl font-semibold text-ink">{mode.counts.pending_jobs}</dd>
+            </div>
+          </dl>
+          <label className="mt-4 block text-xs font-medium text-ink-muted">
+            Reason <span className="text-danger">(required for force retire)</span>
+            <input
+              type="text"
+              value={mode.reason}
+              onChange={(e) => onReasonChange(e.target.value)}
+              placeholder="e.g. rack 7 decommission, cascade retire"
+              className="mt-1 w-full rounded border border-border bg-surface-alt px-2 py-1 text-sm"
+            />
+          </label>
+        </>
+      )}
 
-        {mode.kind === 'error' && (
-          <>
-            <h2 className="text-lg font-semibold text-ink">Retire failed</h2>
-            <p className="mt-2 text-sm text-danger">{mode.message}</p>
-            <div className="mt-6 flex justify-end">
-              <button
-                type="button"
-                onClick={onClose}
-                className="px-4 py-2 text-sm text-ink-muted hover:text-ink"
-              >
-                Close
-              </button>
-            </div>
-          </>
-        )}
-      </div>
-    </div>
+      {mode.kind === 'error' && (
+        <p className="text-sm text-danger">{mode.message}</p>
+      )}
+    </ModalDialog>
   );
 }
diff --git a/web/src/pages/ESTAdminPage.tsx b/web/src/pages/ESTAdminPage.tsx
index a522275..5b7f437 100644
--- a/web/src/pages/ESTAdminPage.tsx
+++ b/web/src/pages/ESTAdminPage.tsx
@@ -7,6 +7,7 @@ import {
   getAuditEvents,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import ErrorState from '../components/ErrorState';
 import { useAuth } from '../components/AuthProvider';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
@@ -276,30 +277,18 @@ interface ConfirmReloadModalProps {
 
 function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessage }: ConfirmReloadModalProps) {
   const pathLabel = profile.path_id || '(legacy /.well-known/est root)';
+  // Phase 5 closure (FE-H3): swapped the inline-managed <div role="dialog">
+  // for ModalDialog (Headless UI) — focus trap + ESC-to-close + backdrop-
+  // click-to-close come for free. Existing test data-testids preserved
+  // verbatim so est-reload-cancel / est-reload-confirm / est-reload-error
+  // assertions keep working.
   return (
-    <div
-      role="dialog"
-      aria-labelledby="est-reload-trust-title"
-      aria-modal="true"
-      className="fixed inset-0 z-50 flex items-center justify-center bg-black/40"
-    >
-      <div className="bg-surface w-full max-w-md rounded-lg shadow-xl border border-surface-border p-6">
-        <h3 id="est-reload-trust-title" className="text-base font-semibold text-ink mb-2">
-          Reload EST mTLS trust anchor
-        </h3>
-        <p className="text-sm text-ink-muted mb-4">
-          This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
-          swaps the trust pool for EST profile <strong>{pathLabel}</strong>. Equivalent to sending
-          <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
-          previous trust pool stays in place — enrollments keep working off the old trust anchor while you
-          fix the file.
-        </p>
-        {errorMessage && (
-          <div className="mb-3 rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800" data-testid="est-reload-error">
-            {errorMessage}
-          </div>
-        )}
-        <div className="flex justify-end gap-2">
+    <ModalDialog
+      open={true}
+      title="Reload EST mTLS trust anchor"
+      onClose={pending ? () => {} : onCancel}
+      footer={
+        <>
           <button
             type="button"
             onClick={onCancel}
@@ -318,9 +307,22 @@ function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessag
           >
             {pending ? 'Reloading…' : 'Reload trust anchor'}
           </button>
+        </>
+      }
+    >
+      <p className="text-sm text-ink-muted mb-3">
+        This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
+        swaps the trust pool for EST profile <strong>{pathLabel}</strong>. Equivalent to sending
+        <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
+        previous trust pool stays in place — enrollments keep working off the old trust anchor while you
+        fix the file.
+      </p>
+      {errorMessage && (
+        <div className="rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800" data-testid="est-reload-error">
+          {errorMessage}
         </div>
-      </div>
-    </div>
+      )}
+    </ModalDialog>
   );
 }
 
diff --git a/web/src/pages/SCEPAdminPage.tsx b/web/src/pages/SCEPAdminPage.tsx
index f891658..e750a43 100644
--- a/web/src/pages/SCEPAdminPage.tsx
+++ b/web/src/pages/SCEPAdminPage.tsx
@@ -8,6 +8,7 @@ import {
   getAuditEvents,
 } from '../api/client';
 import PageHeader from '../components/PageHeader';
+import ModalDialog from '../components/ModalDialog';
 import ErrorState from '../components/ErrorState';
 import { useAuth } from '../components/AuthProvider';
 import { useTrackedMutation } from '../hooks/useTrackedMutation';
@@ -267,30 +268,19 @@ interface ConfirmReloadModalProps {
 
 function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessage }: ConfirmReloadModalProps) {
   const pathLabel = profile.path_id || '(legacy /scep root)';
+  // Phase 5 closure (FE-H3): swapped the inline-managed <div role="dialog">
+  // for ModalDialog (Headless UI) so the operator gets focus trap, ESC-to-
+  // close, and backdrop-click-to-close. Pre-Phase-5 the modal had aria
+  // attrs but no focus management — Tab would escape out of the panel into
+  // the underlying page, and ESC did nothing. ModalDialog wires both to
+  // onCancel automatically.
   return (
-    <div
-      role="dialog"
-      aria-labelledby="reload-trust-title"
-      aria-modal="true"
-      className="fixed inset-0 z-50 flex items-center justify-center bg-black/40"
-    >
-      <div className="bg-surface w-full max-w-md rounded-lg shadow-xl border border-surface-border p-6">
-        <h3 id="reload-trust-title" className="text-base font-semibold text-ink mb-2">
-          Reload Intune trust anchor
-        </h3>
-        <p className="text-sm text-ink-muted mb-4">
-          This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
-          swaps the trust pool for SCEP profile <strong>{pathLabel}</strong>. Equivalent to sending
-          <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
-          previous trust pool stays in place — enrollments keep working off the old trust anchor while you
-          fix the file.
-        </p>
-        {errorMessage && (
-          <div className="mb-3 rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800">
-            {errorMessage}
-          </div>
-        )}
-        <div className="flex justify-end gap-2">
+    <ModalDialog
+      open={true}
+      title="Reload Intune trust anchor"
+      onClose={pending ? () => {} : onCancel}
+      footer={
+        <>
           <button
             type="button"
             onClick={onCancel}
@@ -307,9 +297,22 @@ function ConfirmReloadModal({ profile, onCancel, onConfirm, pending, errorMessag
           >
             {pending ? 'Reloading…' : 'Reload trust anchor'}
           </button>
+        </>
+      }
+    >
+      <p className="text-sm text-ink-muted mb-3">
+        This re-reads <code className="text-xs">{profile.trust_anchor_path}</code> from disk and atomically
+        swaps the trust pool for SCEP profile <strong>{pathLabel}</strong>. Equivalent to sending
+        <code className="text-xs"> SIGHUP </code> to the server. If the new file fails to parse, the
+        previous trust pool stays in place — enrollments keep working off the old trust anchor while you
+        fix the file.
+      </p>
+      {errorMessage && (
+        <div className="rounded border border-red-300 bg-red-50 p-3 text-xs text-red-800">
+          {errorMessage}
         </div>
-      </div>
-    </div>
+      )}
+    </ModalDialog>
   );
 }
 
diff --git a/web/src/pages/onboarding/CertificateStep.tsx b/web/src/pages/onboarding/CertificateStep.tsx
index c97700b..a959928 100644
--- a/web/src/pages/onboarding/CertificateStep.tsx
+++ b/web/src/pages/onboarding/CertificateStep.tsx
@@ -11,81 +11,117 @@
 import { useState } from 'react';
 import { useQuery } from '@tanstack/react-query';
 import { Link } from 'react-router-dom';
+import { useForm } from 'react-hook-form';
+import { zodResolver } from '@hookform/resolvers/zod';
 import { useTrackedMutation } from '../../hooks/useTrackedMutation';
 import {
   getIssuers, getAgents, getProfiles, getOwners, getTeams, getRenewalPolicies,
   createCertificate, triggerRenewal, createTeam, createOwner,
 } from '../../api/client';
+import FormField from '../../components/FormField';
+import ModalDialog from '../../components/ModalDialog';
+import { teamSchema, type TeamFormValues } from './team.schema';
 import { WizardFooter } from './StepShell';
 
 // Inline CreateTeamModal — mirrors TeamsPage.tsx CreateTeamModal pattern.
 // Used inside CertificateStep so users can create a team without leaving the wizard.
+// Phase 5 closure (FE-M1 + UX-H4): converted from 3 useState + manual
+// onChange handlers to react-hook-form + zodResolver + FormField. The
+// FormField primitive auto-pairs <label htmlFor> with <input id> via
+// useId(), so the WCAG 1.3.1 binding contract holds by construction.
+// Zod schema lives in team.schema.ts so it can be reused if another
+// page needs the same create-team contract.
 function CreateTeamModalInline({ isOpen, onClose, onCreated }: {
   isOpen: boolean;
   onClose: () => void;
   onCreated: (teamId: string) => void;
 }) {
-  const [name, setName] = useState('');
-  const [description, setDescription] = useState('');
-  const [error, setError] = useState('');
+  const [serverError, setServerError] = useState('');
+  const {
+    register,
+    handleSubmit,
+    reset,
+    formState: { errors, isSubmitting },
+  } = useForm<TeamFormValues>({
+    resolver: zodResolver(teamSchema),
+    // Validate on submit (which fires when the form-bound footer button
+    // dispatches "submit") rather than gating the button on `isValid`.
+    // RHF's isValid doesn't reliably flip synchronously after a single
+    // fireEvent.change in jsdom — submit-time validation via the Zod
+    // resolver gives the same UX (errors land under the field) without
+    // the timing footgun.
+    mode: 'onSubmit',
+    defaultValues: { name: '', description: '' },
+  });
 
   const mutation = useTrackedMutation({
-    mutationFn: () => createTeam({ name: name.trim(), description: description.trim() }),
+    mutationFn: (values: TeamFormValues) =>
+      createTeam({ name: values.name, description: values.description }),
     invalidates: [['teams']],
     onSuccess: (team) => {
-      setName('');
-      setDescription('');
-      setError('');
+      reset();
+      setServerError('');
       onCreated(team.id);
       onClose();
     },
-    onError: (err: Error) => setError(err.message),
+    onError: (err: Error) => setServerError(err.message),
   });
 
-  if (!isOpen) return null;
+  const onSubmit = (values: TeamFormValues) => {
+    setServerError('');
+    mutation.mutate(values);
+  };
+
   return (
-    <div className="fixed inset-0 bg-black/40 flex items-center justify-center z-50" onClick={onClose}>
-      <div className="bg-surface border border-surface-border rounded p-5 w-full max-w-md shadow-xl" onClick={e => e.stopPropagation()}>
-        <h2 className="text-lg font-semibold text-ink mb-4">Create Team</h2>
-        {error && <div className="mb-4 p-3 bg-red-50 border border-red-200 rounded text-sm text-red-700">{error}</div>}
-        <form onSubmit={(e) => { e.preventDefault(); if (!name.trim()) return; mutation.mutate(); }} className="space-y-4">
-          <div>
-            <label className="block text-sm font-medium text-ink mb-2">
-              Name <span className="text-red-600">*</span>
-            </label>
-            <input
-              type="text"
-              value={name}
-              onChange={e => setName(e.target.value)}
-              placeholder="Platform Engineering"
-              autoFocus
-              className="w-full px-3 py-2 bg-surface border border-surface-border rounded text-ink placeholder-ink-faint focus:outline-none focus:border-brand-500 transition-colors"
-            />
-          </div>
-          <div>
-            <label className="block text-sm font-medium text-ink mb-2">
-              Description <span className="text-xs text-ink-muted font-normal">(optional)</span>
-            </label>
-            <textarea
-              value={description}
-              onChange={e => setDescription(e.target.value)}
-              rows={3}
-              className="w-full px-3 py-2 bg-surface border border-surface-border rounded text-ink placeholder-ink-faint focus:outline-none focus:border-brand-500 transition-colors"
-            />
-          </div>
-          <div className="flex gap-2 pt-2">
-            <button
-              type="submit"
-              disabled={mutation.isPending || !name.trim()}
-              className="flex-1 btn btn-primary disabled:opacity-50 disabled:cursor-not-allowed"
-            >
-              {mutation.isPending ? 'Creating...' : 'Create Team'}
-            </button>
-            <button type="button" onClick={onClose} className="flex-1 btn btn-ghost">Cancel</button>
-          </div>
-        </form>
-      </div>
-    </div>
+    <ModalDialog
+      open={isOpen}
+      title="Create Team"
+      onClose={isSubmitting ? () => {} : () => { reset(); setServerError(''); onClose(); }}
+      footer={
+        <>
+          <button
+            type="button"
+            onClick={() => { reset(); setServerError(''); onClose(); }}
+            disabled={isSubmitting}
+            className="flex-1 btn btn-ghost"
+          >
+            Cancel
+          </button>
+          <button
+            type="submit"
+            form="create-team-form"
+            disabled={isSubmitting}
+            className="flex-1 btn btn-primary disabled:opacity-50 disabled:cursor-not-allowed"
+          >
+            {isSubmitting ? 'Creating...' : 'Create Team'}
+          </button>
+        </>
+      }
+    >
+      {serverError && (
+        <div className="mb-3 p-3 bg-red-50 border border-red-200 rounded text-sm text-red-700">
+          {serverError}
+        </div>
+      )}
+      <form id="create-team-form" onSubmit={handleSubmit(onSubmit)} className="space-y-3">
+        <FormField label="Name" required error={errors.name?.message}>
+          <input
+            type="text"
+            placeholder="Platform Engineering"
+            autoFocus
+            className="w-full px-3 py-2 bg-surface border border-surface-border rounded text-ink placeholder-ink-faint focus:outline-none focus:border-brand-500 transition-colors"
+            {...register('name')}
+          />
+        </FormField>
+        <FormField label="Description" description="Optional — what does this team own?">
+          <textarea
+            rows={3}
+            className="w-full px-3 py-2 bg-surface border border-surface-border rounded text-ink placeholder-ink-faint focus:outline-none focus:border-brand-500 transition-colors"
+            {...register('description')}
+          />
+        </FormField>
+      </form>
+    </ModalDialog>
   );
 }
 
diff --git a/web/src/pages/onboarding/team.schema.ts b/web/src/pages/onboarding/team.schema.ts
new file mode 100644
index 0000000..1774df8
--- /dev/null
+++ b/web/src/pages/onboarding/team.schema.ts
@@ -0,0 +1,33 @@
+// Copyright 2026 certctl LLC. All rights reserved.
+// SPDX-License-Identifier: BUSL-1.1
+//
+// Zod schema for the inline "Create Team" form inside CertificateStep
+// (the wizard's third step). Phase 5 closure scaffolding for FE-M1 +
+// UX-H4 — proves the FormField + react-hook-form + zodResolver pattern
+// on a small, contained form that's part of the operator's first-run
+// experience.
+//
+// Backend contract: POST /api/v1/teams accepts `{ name: string,
+// description?: string }`. Name is required (handler 400s on empty);
+// description is optional. We mirror that here so submit-time
+// validation matches what the server will accept.
+
+import { z } from 'zod';
+
+// Both fields typed as string (no `optional()`) so the schema's input
+// and output types match — RHF + zodResolver require Input == Output
+// when the resolver TFieldValues generic is invariant. Description
+// defaults to '' from the form's defaultValues; the backend treats
+// empty-string and absent identically (handler at internal/api/handler/
+// teams.go:34 calls strings.TrimSpace before checking len).
+export const teamSchema = z.object({
+  name: z
+    .string()
+    .trim()
+    .min(1, 'Team name is required'),
+  description: z
+    .string()
+    .trim(),
+});
+
+export type TeamFormValues = z.infer<typeof teamSchema>;
diff --git a/web/src/test/a11y.test.tsx b/web/src/test/a11y.test.tsx
new file mode 100644
index 0000000..61cd6dd
--- /dev/null
+++ b/web/src/test/a11y.test.tsx
@@ -0,0 +1,112 @@
+// Phase 5 closure (FE-H3 + UX-H4 regression gate): axe-core a11y
+// assertions on the primitives that other pages reuse. Failing this
+// suite means a future change reintroduced an unbound label, a missing
+// aria-* attr on a primitive, or a similar a11y bug.
+//
+// Implementation notes:
+//   • Uses axe-core directly (not jest-axe) — jest-axe's
+//     `toHaveNoViolations` matcher uses the jest expect API, which
+//     Vitest's expect.extend can't host (TypeError: expectAssertion.call
+//     is not a function). Asserting violations.length === 0 with a
+//     readable failure message gives the same gate without the
+//     compatibility headache.
+//   • Scope is primitives, not page sweeps — primitives carry the risk
+//     surface, pages mostly compose them. Faster runtime + tighter
+//     fail signal when a primitive regresses.
+
+import { describe, it, expect } from 'vitest';
+import { render } from '@testing-library/react';
+import axe from 'axe-core';
+import { MemoryRouter } from 'react-router-dom';
+
+import FormField from '../components/FormField';
+import ModalDialog from '../components/ModalDialog';
+import Skeleton from '../components/Skeleton';
+import Breadcrumbs from '../components/Breadcrumbs';
+
+async function expectNoViolations(
+  container: HTMLElement,
+  extraSuppressedRules: string[] = [],
+) {
+  const suppressed: Record<string, { enabled: false }> = {
+    // color-contrast needs computed-styles which jsdom doesn't compute;
+    // that rule is suppressed in axe defaults under jsdom anyway but
+    // pinning it here keeps the failure mode loud if axe-core changes
+    // default behavior.
+    'color-contrast': { enabled: false },
+  };
+  for (const r of extraSuppressedRules) suppressed[r] = { enabled: false };
+  const results = await axe.run(container, { rules: suppressed });
+  if (results.violations.length > 0) {
+    const summary = results.violations
+      .map((v) => `  • ${v.id} (${v.impact}): ${v.help} — ${v.nodes.length} node(s)`)
+      .join('\n');
+    throw new Error(`axe-core found ${results.violations.length} violation(s):\n${summary}`);
+  }
+  expect(results.violations).toHaveLength(0);
+}
+
+describe('Primitives — axe-core a11y assertions', () => {
+  it('FormField (label / input pair) has no axe violations', async () => {
+    const { container } = render(
+      <FormField label="Email address" required>
+        <input type="email" />
+      </FormField>,
+    );
+    await expectNoViolations(container);
+  });
+
+  it('FormField with description + error has no axe violations', async () => {
+    const { container } = render(
+      <FormField
+        label="Display name"
+        required
+        description="What other operators will see"
+        error="Must be at least 1 character"
+      >
+        <input type="text" />
+      </FormField>,
+    );
+    await expectNoViolations(container);
+  });
+
+  it('Skeleton variants have no axe violations (table / page / card / stat)', async () => {
+    for (const variant of ['table', 'page', 'card', 'stat'] as const) {
+      const { container, unmount } = render(<Skeleton variant={variant} />);
+      // Skeleton.table renders empty <th> cells — they're decorative
+      // shimmer placeholders inside a role="status" + aria-busy="true"
+      // container, so screen readers announce "Loading content" and
+      // skip the table semantics. axe-core's `empty-table-header` rule
+      // doesn't model aria-busy gating, so suppress it for this variant
+      // (and consistently across all variants for the same scan).
+      await expectNoViolations(container, ['empty-table-header']);
+      unmount();
+    }
+  });
+
+  it('ModalDialog with title + body + footer has no axe violations', async () => {
+    const { baseElement } = render(
+      <ModalDialog
+        open={true}
+        title="Confirm action"
+        onClose={() => {}}
+        footer={<button>OK</button>}
+      >
+        <p>This action is reversible.</p>
+      </ModalDialog>,
+    );
+    // ModalDialog mounts into a portal on document.body — pass
+    // baseElement (which is document.body) rather than container so
+    // axe scans the actual rendered dialog tree.
+    await expectNoViolations(baseElement);
+  });
+
+  it('Breadcrumbs renders no axe violations on a 2-deep path', async () => {
+    const { container } = render(
+      <MemoryRouter initialEntries={['/issuers/iss-vault']}>
+        <Breadcrumbs />
+      </MemoryRouter>,
+    );
+    await expectNoViolations(container);
+  });
+});