diff --git a/scripts/snippets/diagnostics.py b/scripts/snippets/diagnostics.py
index a5bd8d529..bcefb26e4 100644
--- a/scripts/snippets/diagnostics.py
+++ b/scripts/snippets/diagnostics.py
@@ -7,6 +7,8 @@
     LocalSourcePolicyIssue,
     SnippetSourceAttributeIssue,
     SnippetSourceAttributeRule,
+    SnippetSourceSafetyIssue,
+    SnippetSourceSafetyRule,
 )
 
 LOCAL_SOURCE_REMEDIATION = (
@@ -20,6 +22,10 @@
     SnippetSourceAttributeRule.LOCAL_PATH_FORBIDDEN: "SNIP006",
     SnippetSourceAttributeRule.UNSUPPORTED_SOURCE: "SNIP008",
 }
+SOURCE_SAFETY_CODES = {
+    SnippetSourceSafetyRule.UNREGISTERED_REPOSITORY: "SNIP009",
+    SnippetSourceSafetyRule.UNSAFE_PATH: "SNIP010",
+}
 
 
 def local_source_policy_diagnostic(
@@ -50,3 +56,19 @@ def snippet_source_attribute_diagnostics(
         )
         for issue in issues
     )
+
+
+def snippet_source_safety_diagnostics(
+    path: Path, issues: tuple[SnippetSourceSafetyIssue, ...]
+) -> tuple[Diagnostic, ...]:
+    """Assign stable diagnostic codes to source-safety failures."""
+
+    return tuple(
+        Diagnostic(
+            path=path,
+            span=issue.span,
+            code=SOURCE_SAFETY_CODES[issue.rule],
+            message=issue.message,
+        )
+        for issue in issues
+    )
diff --git a/tests/test_snippet_source_safety_diagnostics.py b/tests/test_snippet_source_safety_diagnostics.py
new file mode 100644
index 000000000..2340e6d55
--- /dev/null
+++ b/tests/test_snippet_source_safety_diagnostics.py
@@ -0,0 +1,38 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from scripts.snippets.diagnostics import snippet_source_safety_diagnostics
+from scripts.snippets.model import (
+    SnippetSourceSafetyIssue,
+    SnippetSourceSafetyRule,
+    Span,
+)
+
+PATH = Path("docs-main/validator.source.mdx")
+SPAN = Span(start=20, end=30, line=7, column=3)
+
+
+@pytest.mark.parametrize(
+    ("rule", "code"),
+    [
+        (SnippetSourceSafetyRule.UNREGISTERED_REPOSITORY, "SNIP009"),
+        (SnippetSourceSafetyRule.UNSAFE_PATH, "SNIP010"),
+    ],
+)
+def test_maps_source_safety_rule_to_stable_code(
+    rule: SnippetSourceSafetyRule, code: str
+) -> None:
+    diagnostics = snippet_source_safety_diagnostics(
+        PATH,
+        (
+            SnippetSourceSafetyIssue(
+                rule=rule, span=SPAN, message="failure"
+            ),
+        ),
+    )
+
+    assert diagnostics[0].code == code
+    assert diagnostics[0].span == SPAN