diff --git a/docs/api-stability.md b/docs/api-stability.md
index 3b2ad5c..6a36637 100644
--- a/docs/api-stability.md
+++ b/docs/api-stability.md
@@ -49,8 +49,8 @@ that need a frozen API should pin a minor release (for example, `~=0.4.0`).
 
 The core package requires Python `>=3.10` and currently tests CPython 3.10
 through 3.14 on Linux, macOS, and Windows. The core runtime dependency is
-Click `>=8.1,<8.5`; the compatibility suite covers the 8.1, 8.2, 8.3, and
-8.4 lines on Python 3.10 and 3.14. YAML configuration and YAML output are provided by the
+Click `>=8.1,<8.6`; the compatibility suite covers the 8.1, 8.2, 8.3, 8.4,
+and 8.5 lines on Python 3.10 and 3.14. YAML configuration and YAML output are provided by the
 optional `base-cli[yaml]` extra, which supplies PyYAML `>=6.0,<7`. Other
 optional integrations are independently versioned and constrained in `pyproject.toml`: Typer
 `>=0.12,<0.28`, Rich `>=13.7,<15`, and OpenTelemetry API `>=1.24,<2`. The
diff --git a/docs/platform-support.md b/docs/platform-support.md
index 677b6ac..5c87c01 100644
--- a/docs/platform-support.md
+++ b/docs/platform-support.md
@@ -36,8 +36,8 @@ filesystem.
 
 ## Dependency support
 
-The core runtime dependency contract is Click `>=8.1,<8.5`, tested across the
-8.1 through 8.4 lines. YAML configuration
+The core runtime dependency contract is Click `>=8.1,<8.6`, tested across the
+8.1 through 8.5 lines. YAML configuration
 and YAML output use the optional `base-cli[yaml]` extra, which supplies PyYAML
 `>=6.0,<7`. The lower bound is the oldest supported line; the upper bound
 prevents an unreviewed major release from entering a production install. The
diff --git a/tests/test_dependency_documentation.py b/tests/test_dependency_documentation.py
new file mode 100644
index 0000000..903d299
--- /dev/null
+++ b/tests/test_dependency_documentation.py
@@ -0,0 +1,29 @@
+from __future__ import annotations
+
+import re
+import unittest
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+class DependencyDocumentationTests(unittest.TestCase):
+    def test_click_window_is_consistent_across_metadata_and_public_docs(self) -> None:
+        metadata = (ROOT / "pyproject.toml").read_text(encoding="utf-8")
+        documents = "\n".join(
+            (ROOT / path).read_text(encoding="utf-8")
+            for path in (
+                "docs/dependency-support.md",
+                "docs/platform-support.md",
+                "docs/api-stability.md",
+                "docs/compatibility-dashboard.md",
+            )
+        )
+        self.assertIn('"click>=8.1,<8.6"', metadata)
+        self.assertRegex(documents, re.compile(r"Click `>=8\.1,<8\.6`"))
+        self.assertIn("8.1, 8.2, 8.3, 8.4, 8.5", documents)
+        self.assertNotIn("Click `>=8.1,<8.5`", documents)
+
+
+if __name__ == "__main__":
+    unittest.main()