diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 0a8f84c..0a6f59f 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -32,6 +32,9 @@ jobs:
       - name: 🧪 Test active Admins policy
         run: bash tests/admin-team-policy.sh
 
+      - name: 🧪 Test declarative coverage
+        run: bash tests/declarative-coverage.sh
+
   ci-required-checks:
     name: CI - Required Checks
     runs-on: ubuntu-latest
diff --git a/AGENTS.md b/AGENTS.md
index a8be975..fb4bb6c 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -76,9 +76,13 @@ structure; implementing PRs use `Fixes #N`.
 **Validate before every PR** (the sole required check, `CI - Required Checks`, gates on this):
 
 ```sh
-kubectl kustomize deploy/ > /dev/null   # must build clean; this is exactly what ci.yaml runs
+kubectl kustomize deploy/ > /dev/null   # must build clean
+bash tests/admin-team-policy.sh         # Admins policy invariants
+bash tests/declarative-coverage.sh      # every repo declared in every rendered dimension
 ```
 
+Those three commands are exactly what `ci.yaml` runs.
+
 `kubectl` (with built-in kustomize) is preinstalled on CI runners. A clean build proves the manifests
 are well-formed; the Crossplane CRDs themselves are applied/validated **on-cluster** (the
 `github-config` tenant), not in CI — so a green build is necessary but not sufficient, and any new CR
diff --git a/deploy/README.md b/deploy/README.md
index eb1c0d4..6eed161 100644
--- a/deploy/README.md
+++ b/deploy/README.md
@@ -93,6 +93,8 @@ before every PR with exactly what CI runs:
 
 ```sh
 kubectl kustomize deploy/ > /dev/null
+bash tests/admin-team-policy.sh
+bash tests/declarative-coverage.sh
 ```
 
 See the platform repo's
@@ -119,4 +121,9 @@ production render and policy invariants with:
 ```sh
 kubectl kustomize deploy/ > /dev/null
 bash tests/admin-team-policy.sh
+bash tests/declarative-coverage.sh
 ```
+
+`declarative-coverage.sh` reads the **rendered** output, so it also catches a
+manifest that exists on disk but was never wired into its directory's
+`kustomization.yaml` — that file renders to nothing and never reconciles.
diff --git a/tests/declarative-coverage.sh b/tests/declarative-coverage.sh
new file mode 100755
index 0000000..51a3bfb
--- /dev/null
+++ b/tests/declarative-coverage.sh
@@ -0,0 +1,165 @@
+#!/usr/bin/env bash
+#
+# Guards the *completeness* of the declarative model in deploy/.
+#
+# Every repository the org manages should appear in every deploy/ dimension.
+# When a repo is created or renamed it is typically added to one or two
+# dimensions and quietly missed in the rest, leaving it partly declared: it
+# looks managed on inspection while un-modelled settings drift underneath.
+#
+# Coverage is read from the RENDERED output of `kubectl kustomize deploy/`,
+# never from the filenames on disk, because only rendered resources reconcile:
+#   - a manifest not listed in its directory's kustomization.yaml renders to
+#     nothing (repository-permissions/ is deliberately in that state today), and
+#   - a renamed file whose forProvider still names the old repo would look
+#     declared under a filename-based check while reconciling the old repo.
+# Both are exactly the partial-rename / partial-add drift this guard exists to
+# catch, so the rendered manifest is the only trustworthy source.
+
+set -euo pipefail
+
+repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+fail() {
+  echo "declarative-coverage test: $*" >&2
+  exit 1
+}
+
+for tool in kubectl yq; do
+  command -v "$tool" >/dev/null || fail "required tool '$tool' not found"
+done
+
+render="$(mktemp)"
+work="$(mktemp -d)"
+trap 'rm -f "$render"; rm -rf "$work"' EXIT
+
+kubectl kustomize "$repo_root/deploy" >"$render" ||
+  fail "kubectl kustomize deploy/ failed"
+[[ -s "$render" ]] || fail "rendered output is empty"
+
+# Dimensions, as "<label>:<yq selector producing one repo name per line>".
+# Each selector runs against the rendered multi-document stream.
+dimensions=(
+  'repositories:select(.kind=="Repository" and .spec.forProvider.archived!=true)|.spec.forProvider.name'
+  'labels:select(.kind=="IssueLabels")|.spec.forProvider.repository'
+  'team-admins:select(.kind=="TeamRepository" and .spec.forProvider.teamIdRef.name=="admins")|.spec.forProvider.repository'
+  'team-maintainers:select(.kind=="TeamRepository" and .spec.forProvider.teamIdRef.name=="maintainers")|.spec.forProvider.repository'
+)
+
+# Deliberate omissions, as "<dimension>/<repo>".
+# An exemption is DECLARED INTENT — it keeps a known gap visible and reviewable
+# instead of silently absent. Prune entries as gaps close; never add one to
+# silence a fresh failure without a tracked reason. The guard fails on a stale
+# exemption, so this list cannot rot.
+exemptions=(
+  # Tracked in devantler-tech/.github#115 — pre-existing gaps found when this
+  # guard was introduced. Exempted so the guard can land green and ratchet:
+  # it fails on any NEW drift while these are closed separately.
+  "repositories/actions"
+  "repositories/.github"
+  "repositories/monorepo"
+  "team-maintainers/agent-plugins"
+  "team-maintainers/agent-skills"
+  "team-maintainers/ascoachingogvaner"
+  "team-maintainers/.github"
+  "team-maintainers/fleet-gitops"
+  "team-maintainers/maintenance"
+  "team-maintainers/wedding-app"
+)
+
+is_exempt() {
+  local needle="$1" entry
+  # "${arr[@]}" on an empty array is an unbound-variable error under `set -u` on
+  # bash < 4.4. This list is meant to shrink to empty as gaps close, so that end
+  # state has to work everywhere, not just on the CI runner.
+  ((${#exemptions[@]} == 0)) && return 1
+  for entry in "${exemptions[@]}"; do
+    [[ "$entry" == "$needle" ]] && return 0
+  done
+  return 1
+}
+
+# --- Collect the declared repos per dimension --------------------------------
+labels=()
+for spec in "${dimensions[@]}"; do
+  label="${spec%%:*}"
+  selector="${spec#*:}"
+  labels+=("$label")
+
+  if ! repos="$(yq -N "$selector" "$render")"; then
+    fail "dimension '$label': yq selector failed"
+  fi
+
+  # `yq -N` suppresses the --- separators that would otherwise be read back as
+  # repository names; drop blanks and nulls defensively as well.
+  repos="$(printf '%s\n' "$repos" | grep -vE '^$|^null$|^---$' | sort -u || true)"
+
+  # A dimension that yields nothing is a broken selector, never "nothing to do".
+  [[ -n "$repos" ]] || fail "dimension '$label': no repositories rendered (broken selector?)"
+
+  printf '%s\n' "$repos" >"$work/$label"
+done
+
+expected="$(cat "$work"/* | sort -u)"
+expected_count="$(printf '%s\n' "$expected" | wc -l | tr -d ' ')"
+
+# The union must be non-trivial; a collapsed set would make every check vacuous.
+[[ "$expected_count" -ge 10 ]] ||
+  fail "expected repository set collapsed to $expected_count entries — refusing to run vacuously"
+
+# --- Compare every dimension against the union -------------------------------
+missing_report=""
+missing_count=0
+exempt_count=0
+
+for label in "${labels[@]}"; do
+  while IFS= read -r repo; do
+    [[ -n "$repo" ]] || continue
+    if ! grep -Fxq "$repo" "$work/$label"; then
+      if is_exempt "$label/$repo"; then
+        exempt_count=$((exempt_count + 1))
+      else
+        missing_report="${missing_report}  - ${label}: ${repo}"$'\n'
+        missing_count=$((missing_count + 1))
+      fi
+    fi
+  done <<<"$expected"
+done
+
+# --- Verify every exemption is still real and still relevant -----------------
+# Two ways an exemption goes stale: the gap was closed (the repo now IS declared
+# in that dimension), or the repo left the model entirely (renamed/removed), in
+# which case a dead entry could later mask a partial re-add of the same name.
+stale_report=""
+for entry in ${exemptions[@]+"${exemptions[@]}"}; do
+  label="${entry%%/*}"
+  repo="${entry#*/}"
+  [[ -f "$work/$label" ]] || fail "exemption '$entry' names unknown dimension '$label'"
+  if grep -Fxq "$repo" "$work/$label"; then
+    stale_report="${stale_report}  - ${entry} — now declared; delete this exemption"$'\n'
+  elif ! printf '%s\n' "$expected" | grep -Fxq "$repo"; then
+    stale_report="${stale_report}  - ${entry} — repo is no longer in the model; delete this exemption"$'\n'
+  fi
+done
+
+if [[ -n "$stale_report" ]]; then
+  echo "declarative-coverage test: stale exemption(s) in tests/declarative-coverage.sh:" >&2
+  printf '%s' "$stale_report" >&2
+  exit 1
+fi
+
+if [[ "$missing_count" -gt 0 ]]; then
+  echo "declarative-coverage test: $missing_count repository/dimension pair(s) are not declared" >&2
+  echo "in the rendered deploy/ output. Add the missing manifest (and wire it into that" >&2
+  echo "directory's kustomization.yaml), or add an exemption with a tracked reason:" >&2
+  printf '%s' "$missing_report" >&2
+  exit 1
+fi
+
+echo "declarative-coverage: OK — $expected_count repositories across ${#labels[@]} rendered" \
+  "dimensions ($exempt_count declared exemption(s))"
+
+# KNOWN LIMITATION: the expected set is the union of repos already present in the
+# rendered model, so a repository absent from EVERY dimension is invisible here.
+# Closing that needs a live org listing, and CI runs with `permissions: {}` and no
+# token; tracked separately rather than bolted on.