diff --git a/.github/workflows/fhir-validation.yml b/.github/workflows/fhir-validation.yml
index 5089fda..e2a0e12 100644
--- a/.github/workflows/fhir-validation.yml
+++ b/.github/workflows/fhir-validation.yml
@@ -148,6 +148,7 @@ jobs:
           echo "No relevant FHIR JSON/XML changes were detected in tracked spec folders. Validation skipped." >> "$GITHUB_STEP_SUMMARY"
 
       - name: Validate meta.profile presence and prefix
+        id: precheck
         if: steps.collect_files.outputs.has_target_files == 'true'
         shell: bash
         run: |
@@ -156,6 +157,8 @@ jobs:
           REQUIRED_PREFIX="http://hl7.eu/fhir/"
           MISSING_PROFILE=()
           MISSING_REQUIRED_PREFIX=()
+          : > .ci/precheck-missing-profile.txt
+          : > .ci/precheck-missing-prefix.txt
 
           while IFS= read -r file; do
             [[ -z "$file" ]] && continue
@@ -185,6 +188,7 @@ jobs:
 
             if [[ -z "$PROFILE_LINES" ]]; then
               MISSING_PROFILE+=("$file")
+              echo "$file" >> .ci/precheck-missing-profile.txt
               continue
             fi
 
@@ -199,6 +203,7 @@ jobs:
 
             if [[ "$HAS_REQUIRED_PREFIX" != "true" ]]; then
               MISSING_REQUIRED_PREFIX+=("$file")
+              echo "$file" >> .ci/precheck-missing-prefix.txt
             fi
           done < .ci/target-files.txt
 
@@ -223,13 +228,18 @@ jobs:
               echo
             fi
 
-            exit 1
+            echo "precheck_exit_code=1" >> "$GITHUB_OUTPUT"
+            echo "missing_profile_count=${#MISSING_PROFILE[@]}" >> "$GITHUB_OUTPUT"
+            echo "missing_required_prefix_count=${#MISSING_REQUIRED_PREFIX[@]}" >> "$GITHUB_OUTPUT"
+          else
+            echo "meta.profile precheck passed for all candidate resources."
+            echo "precheck_exit_code=0" >> "$GITHUB_OUTPUT"
+            echo "missing_profile_count=0" >> "$GITHUB_OUTPUT"
+            echo "missing_required_prefix_count=0" >> "$GITHUB_OUTPUT"
           fi
 
-          echo "meta.profile precheck passed for all candidate resources."
-
       - name: Set up Java
-        if: steps.collect_files.outputs.has_target_files == 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0'
         uses: actions/setup-java@v5
         with:
           distribution: temurin
@@ -237,7 +247,7 @@ jobs:
 
       - name: Resolve validator download URL
         id: validator_meta
-        if: steps.collect_files.outputs.has_target_files == 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0'
         shell: bash
         run: |
           set -euo pipefail
@@ -263,7 +273,7 @@ jobs:
           echo "cache_key=validator-cli-${CACHE_SUFFIX}" >> "$GITHUB_OUTPUT"
 
       - name: Restore cached validator
-        if: steps.collect_files.outputs.has_target_files == 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0'
         id: validator_cache
         uses: actions/cache@v5
         with:
@@ -273,7 +283,7 @@ jobs:
             ${{ runner.os }}-validator-cli-
 
       - name: Download validator if cache miss
-        if: steps.collect_files.outputs.has_target_files == 'true' && steps.validator_cache.outputs.cache-hit != 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0' && steps.validator_cache.outputs.cache-hit != 'true'
         shell: bash
         run: |
           set -euo pipefail
@@ -283,7 +293,7 @@ jobs:
 
       - name: Run Java FHIR validator
         id: run_validator
-        if: steps.collect_files.outputs.has_target_files == 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0'
         shell: bash
         run: |
           set -euo pipefail
@@ -323,7 +333,7 @@ jobs:
 
       - name: Render validation summary
         id: render_summary
-        if: steps.collect_files.outputs.has_target_files == 'true'
+        if: steps.collect_files.outputs.has_target_files == 'true' && steps.precheck.outputs.precheck_exit_code == '0'
         continue-on-error: false
         uses: patrick-werner/validation-outcome-markdown-renderer@v1
         with:
@@ -341,11 +351,87 @@ jobs:
             printf '%s\n' \
               '# FHIR Validation Summary' \
               '' \
-              'The markdown summary could not be rendered from `validation.json`.' \
+              'The markdown summary could not be rendered from `validation.json` or validation was skipped due to precheck issues.' \
               'Please check the workflow logs and the uploaded HTML artifact for details.' \
               > pr-summary.md
           fi
 
+      - name: Build precheck summary
+        if: always() && steps.collect_files.outputs.has_target_files == 'true'
+        shell: bash
+        run: |
+          set -euo pipefail
+
+          PRECHECK_EXIT="${{ steps.precheck.outputs.precheck_exit_code }}"
+          MISSING_PROFILE_COUNT="${{ steps.precheck.outputs.missing_profile_count }}"
+          MISSING_PREFIX_COUNT="${{ steps.precheck.outputs.missing_required_prefix_count }}"
+          REQUIRED_PREFIX="http://hl7.eu/fhir/"
+          MAX_LIST_ITEMS=80
+
+          if [[ -z "$PRECHECK_EXIT" ]]; then
+            PRECHECK_EXIT="0"
+          fi
+          if [[ -z "$MISSING_PROFILE_COUNT" ]]; then
+            MISSING_PROFILE_COUNT="0"
+          fi
+          if [[ -z "$MISSING_PREFIX_COUNT" ]]; then
+            MISSING_PREFIX_COUNT="0"
+          fi
+
+          {
+            echo "## meta.profile precheck"
+            echo
+            if [[ "$PRECHECK_EXIT" == "0" ]]; then
+              echo "<!-- PRECHECK_STATUS:PASSED -->"
+              echo
+              echo "✅ Passed: every checked resource contains \`meta.profile\` and has at least one entry starting with \`${REQUIRED_PREFIX}\`."
+            else
+              echo "<!-- PRECHECK_STATUS:FAILED -->"
+              echo
+              echo "❌ Failed."
+              echo
+              echo "- Missing \`meta.profile\`: ${MISSING_PROFILE_COUNT}"
+              echo "- No \`meta.profile\` entry with required prefix \`${REQUIRED_PREFIX}\`: ${MISSING_PREFIX_COUNT}"
+              echo
+
+              if [[ -s .ci/precheck-missing-profile.txt ]]; then
+                echo "### Missing \`meta.profile\`"
+                count=0
+                while IFS= read -r file; do
+                  [[ -z "$file" ]] && continue
+                  echo "- \`$file\`"
+                  count=$((count + 1))
+                  if [[ "$count" -ge "$MAX_LIST_ITEMS" ]]; then
+                    break
+                  fi
+                done < .ci/precheck-missing-profile.txt
+                total="$(wc -l < .ci/precheck-missing-profile.txt | tr -d ' ')"
+                if [[ "$total" -gt "$MAX_LIST_ITEMS" ]]; then
+                  echo "- _...truncated (${MAX_LIST_ITEMS} of ${total})_"
+                fi
+                echo
+              fi
+
+              if [[ -s .ci/precheck-missing-prefix.txt ]]; then
+                echo "### No required prefix in \`meta.profile\`"
+                count=0
+                while IFS= read -r file; do
+                  [[ -z "$file" ]] && continue
+                  echo "- \`$file\`"
+                  count=$((count + 1))
+                  if [[ "$count" -ge "$MAX_LIST_ITEMS" ]]; then
+                    break
+                  fi
+                done < .ci/precheck-missing-prefix.txt
+                total="$(wc -l < .ci/precheck-missing-prefix.txt | tr -d ' ')"
+                if [[ "$total" -gt "$MAX_LIST_ITEMS" ]]; then
+                  echo "- _...truncated (${MAX_LIST_ITEMS} of ${total})_"
+                fi
+                echo
+              fi
+            fi
+          } > precheck-summary.md
+
       - name: Write PR metadata
         if: always()
         shell: bash
@@ -376,6 +462,14 @@ jobs:
           path: pr-summary.md
           if-no-files-found: warn
 
+      - name: Upload precheck summary artifact
+        if: always() && steps.collect_files.outputs.has_target_files == 'true'
+        uses: actions/upload-artifact@v7
+        with:
+          name: fhir-validation-precheck-summary
+          path: precheck-summary.md
+          if-no-files-found: warn
+
       - name: Upload validation reports (HTML + JSON)
         id: upload_html_report
         if: always() && steps.collect_files.outputs.has_target_files == 'true'
@@ -393,7 +487,20 @@ jobs:
         run: |
           set -euo pipefail
 
+          PRECHECK_EXIT="${{ steps.precheck.outputs.precheck_exit_code }}"
           EXIT_CODE="${{ steps.run_validator.outputs.validator_exit_code }}"
+          if [[ -z "$PRECHECK_EXIT" ]]; then
+            PRECHECK_EXIT="0"
+          fi
+          if [[ -z "$EXIT_CODE" ]]; then
+            EXIT_CODE="0"
+          fi
+
+          if [[ "$PRECHECK_EXIT" != "0" ]]; then
+            echo "FHIR validation precheck failed (meta.profile requirements not met)."
+            exit 1
+          fi
+
           if [[ "$EXIT_CODE" != "0" ]]; then
             echo "FHIR validation finished with errors (exit code: $EXIT_CODE)."
             exit 1
diff --git a/.github/workflows/main-validation-readme.yml b/.github/workflows/main-validation-readme.yml
index ec008ee..a2b0420 100644
--- a/.github/workflows/main-validation-readme.yml
+++ b/.github/workflows/main-validation-readme.yml
@@ -19,7 +19,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
@@ -195,7 +195,7 @@ jobs:
 
       - name: Set up Java
         if: steps.collect_files.outputs.has_target_files == 'true'
-        uses: actions/setup-java@v5
+        uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: '21'
@@ -230,7 +230,7 @@ jobs:
       - name: Restore cached validator
         if: steps.collect_files.outputs.has_target_files == 'true'
         id: validator_cache
-        uses: actions/cache@v5
+        uses: actions/cache@v4
         with:
           path: .cache/fhir-validator/validator_cli.jar
           key: ${{ runner.os }}-${{ steps.validator_meta.outputs.cache_key }}
@@ -543,7 +543,7 @@ jobs:
     steps:
       - name: Download main validation artifacts
         id: download_artifacts
-        uses: actions/download-artifact@v8
+        uses: actions/download-artifact@v4
         continue-on-error: true
         with:
           name: main-validation-artifacts
@@ -605,7 +605,7 @@ jobs:
           } > .ci-pages/site/index.html
 
       - name: Upload Pages artifact
-        uses: actions/upload-pages-artifact@v5
+        uses: actions/upload-pages-artifact@v3
         with:
           path: .ci-pages/site
 
diff --git a/.github/workflows/pr-comment.yml b/.github/workflows/pr-comment.yml
index 69d8bc1..5b7cfe2 100644
--- a/.github/workflows/pr-comment.yml
+++ b/.github/workflows/pr-comment.yml
@@ -69,6 +69,7 @@ jobs:
 
           META_ARTIFACT_ID="$(echo "$ARTIFACTS_JSON" | jq -r '.artifacts[] | select(.name == "fhir-validation-pr-meta" and .expired == false) | .id' | head -n 1)"
           SUMMARY_ARTIFACT_ID="$(echo "$ARTIFACTS_JSON" | jq -r '.artifacts[] | select(.name == "fhir-validation-pr-summary" and .expired == false) | .id' | head -n 1)"
+          PRECHECK_ARTIFACT_ID="$(echo "$ARTIFACTS_JSON" | jq -r '.artifacts[] | select(.name == "fhir-validation-precheck-summary" and .expired == false) | .id' | head -n 1)"
           HTML_ARTIFACT_ID="$(echo "$ARTIFACTS_JSON" | jq -r '.artifacts[] | select(.name == "fhir-validation-html-report" and .expired == false) | .id' | head -n 1)"
 
           if [[ -z "$META_ARTIFACT_ID" ]]; then
@@ -133,6 +134,18 @@ jobs:
             fi
           fi
 
+          PRECHECK_SUMMARY_FILE=""
+          if [[ -n "$PRECHECK_ARTIFACT_ID" ]]; then
+            mkdir -p .ci-comment/source-precheck
+            curl -fsSL \
+              -H "Authorization: Bearer $GH_TOKEN" \
+              -H "Accept: application/vnd.github+json" \
+              "https://api.github.com/repos/$REPOSITORY/actions/artifacts/$PRECHECK_ARTIFACT_ID/zip" \
+              -o .ci-comment/precheck-summary.zip
+            unzip -qo .ci-comment/precheck-summary.zip -d .ci-comment/source-precheck
+            PRECHECK_SUMMARY_FILE="$(find .ci-comment/source-precheck -type f -name 'precheck-summary.md' | head -n 1 || true)"
+          fi
+
           # Prefer full renderer summary first.
           if [[ -s "$FULL_SUMMARY_FILE" ]]; then
             cp "$FULL_SUMMARY_FILE" "$COMMENT_FILE"
@@ -168,6 +181,7 @@ jobs:
           echo "html_artifact_url=$HTML_ARTIFACT_URL" >> "$GITHUB_OUTPUT"
           echo "run_url=$RUN_URL" >> "$GITHUB_OUTPUT"
           echo "full_summary_file=$FULL_SUMMARY_FILE" >> "$GITHUB_OUTPUT"
+          echo "precheck_summary_file=$PRECHECK_SUMMARY_FILE" >> "$GITHUB_OUTPUT"
 
           echo "has_pr=true" >> "$GITHUB_OUTPUT"
           echo "pr_number=$PR_NUMBER" >> "$GITHUB_OUTPUT"
@@ -190,6 +204,7 @@ jobs:
           COMMENT_FILE=".ci-comment/pr-summary.md"
           FINAL_FILE=".ci-comment/pr-summary-final.md"
           FULL_FILE="${{ steps.build_comment.outputs.full_summary_file }}"
+          PRECHECK_FILE="${{ steps.build_comment.outputs.precheck_summary_file }}"
           FILTERED_RENDERED_FILE=".ci-comment/pr-summary-errors-only-rendered.md"
           MAX_COMMENT_BYTES=62000
           HTML_ARTIFACT_URL="${{ steps.build_comment.outputs.html_artifact_url }}"
@@ -226,6 +241,15 @@ jobs:
               > "$FINAL_FILE"
           fi
 
+          if [[ -n "$PRECHECK_FILE" && -s "$PRECHECK_FILE" ]] && grep -q 'PRECHECK_STATUS:FAILED' "$PRECHECK_FILE"; then
+            {
+              cat "$PRECHECK_FILE"
+              printf '\n---\n\n'
+              cat "$FINAL_FILE"
+            } > .ci-comment/pr-summary-with-precheck.md
+            mv .ci-comment/pr-summary-with-precheck.md "$FINAL_FILE"
+          fi
+
           printf '\n## Artifacts\n\n[Download `fhir-validation-html-report` (includes `validation.html` and `validation.json`)](%s)\n' "$HTML_ARTIFACT_URL" >> "$FINAL_FILE"
           printf '\nValidation run: %s\n' "$RUN_URL" >> "$FINAL_FILE"