diff --git a/docs/cli/t4sanity.md b/docs/cli/t4sanity.md
index fe074c9..09dd8d8 100644
--- a/docs/cli/t4sanity.md
+++ b/docs/cli/t4sanity.md
@@ -13,7 +13,6 @@ $ t4sanity -h
 │ --output              -o       TEXT  Path to output JSON file. [default: None]                                        │
 │ --revision            -rv      TEXT  Specify if you want to check the specific version. [default: None]               │
 │ --exclude             -e       TEXT  Exclude specific rules or rule groups. [default: None]                           │
-│ --include-warning     -iw            Indicates whether to report any warnings.                                        │
 │ --strict              -s             Indicates whether warnings are treated as failures.                              │
 │ --install-completion                 Install completion for the current shell.                                        │
 │ --show-completion                    Show completion for the current shell, to copy it or customize the installation. │
diff --git a/t4_devkit/cli/sanity.py b/t4_devkit/cli/sanity.py
index facdcd2..6c5ed79 100644
--- a/t4_devkit/cli/sanity.py
+++ b/t4_devkit/cli/sanity.py
@@ -36,19 +36,14 @@ def main(
     excludes: list[str] | None = typer.Option(
         None, "-e", "--exclude", help="Exclude specific rules or rule groups."
     ),
-    include_warning: bool = typer.Option(
-        False, "-iw", "--include-warning", help="Indicates whether to report any warnings."
-    ),
     strict: bool = typer.Option(
-        False, "-s", "--strict", help="Indicates whether warnings are treated as failures."
+        False,
+        "-s",
+        "--strict",
+        help="By default, warnings do not cause failure. If set, warnings are treated as failures.",
     ),
 ) -> None:
-    result = sanity_check(
-        data_root=data_root,
-        revision=revision,
-        excludes=excludes,
-        include_warning=include_warning,
-    )
+    result = sanity_check(data_root=data_root, revision=revision, excludes=excludes)
 
     print_sanity_result(result, strict=strict)
 
diff --git a/t4_devkit/sanity/run.py b/t4_devkit/sanity/run.py
index cd62ab9..ae91431 100644
--- a/t4_devkit/sanity/run.py
+++ b/t4_devkit/sanity/run.py
@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import warnings
 from typing import Sequence
 
 from .context import SanityContext
@@ -14,7 +13,6 @@ def sanity_check(
     data_root: str,
     revision: str | None = None,
     *,
-    include_warning: bool = False,
     excludes: Sequence[str] | None = None,
 ) -> SanityResult:
     """Run sanity checks on the given data root.
@@ -22,21 +20,14 @@ def sanity_check(
     Args:
         data_root (str): The root directory of the data.
         revision (str | None, optional): The revision to check. If None, the latest revision is used.
-        include_warning (bool, optional): Whether to include warning checks.
         excludes (Sequence[str] | None, optional): A list of rule names or groups to exclude.
 
     Returns:
         A SanityResult object.
     """
-    with warnings.catch_warnings():
-        if include_warning:
-            warnings.simplefilter("error")
-        else:
-            warnings.simplefilter("ignore")
+    context = SanityContext.from_path(data_root, revision=revision)
 
-        context = SanityContext.from_path(data_root, revision=revision)
+    checkers = CHECKERS.build(excludes=excludes)
+    reports = [checker(context) for checker in checkers]
 
-        checkers = CHECKERS.build(excludes=excludes)
-        reports = [checker(context) for checker in checkers]
-
-        return SanityResult.from_context(context, reports)
+    return SanityResult.from_context(context, reports)