diff --git a/mcpgateway/alembic/versions/878e287d2366_resize_url_and_slug_columns_to_191.py b/mcpgateway/alembic/versions/878e287d2366_resize_url_and_slug_columns_to_191.py
new file mode 100644
index 000000000..698fe2af4
--- /dev/null
+++ b/mcpgateway/alembic/versions/878e287d2366_resize_url_and_slug_columns_to_191.py
@@ -0,0 +1,130 @@
+"""" resize url and slug columns to 191"
+
+Revision ID: 878e287d2366
+Revises: 3c89a45f32e5
+Create Date: 2025-10-08 09:08:35.363100
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = '878e287d2366'
+down_revision: Union[str, Sequence[str], None] = '3c89a45f32e5'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # Get database dialect for dialect-specific operations
+    bind = op.get_bind()
+    dialect_name = bind.dialect.name
+
+    # Truncate existing values longer than 191 chars using dialect-appropriate functions
+    if dialect_name == 'sqlite':
+        # SQLite uses SUBSTR and LENGTH
+        op.execute("""
+            UPDATE gateways
+            SET slug = SUBSTR(slug, 1, 191),
+                url = SUBSTR(url, 1, 191)
+            WHERE LENGTH(slug) > 191 OR LENGTH(url) > 191;
+        """)
+    elif dialect_name == 'postgresql':
+        # PostgreSQL supports LEFT and CHAR_LENGTH
+        op.execute("""
+            UPDATE gateways
+            SET slug = LEFT(slug, 191),
+                url = LEFT(url, 191)
+            WHERE CHAR_LENGTH(slug) > 191 OR CHAR_LENGTH(url) > 191;
+        """)
+    elif dialect_name == 'mysql':
+        # MySQL supports LEFT and CHAR_LENGTH (character-based, not byte-based)
+        op.execute("""
+            UPDATE gateways
+            SET slug = LEFT(slug, 191),
+                url = LEFT(url, 191)
+            WHERE CHAR_LENGTH(slug) > 191 OR CHAR_LENGTH(url) > 191;
+        """)
+    else:
+        # Fallback for other databases
+        op.execute("""
+            UPDATE gateways
+            SET slug = SUBSTR(slug, 1, 191),
+                url = SUBSTR(url, 1, 191)
+            WHERE LENGTH(slug) > 191 OR LENGTH(url) > 191;
+        """)
+
+    # Resize columns to String(191)
+    # SQLite requires batch operations for ALTER COLUMN
+    if dialect_name == 'sqlite':
+        with op.batch_alter_table('gateways', schema=None) as batch_op:
+            batch_op.alter_column(
+                'slug',
+                existing_type=sa.String(length=255),
+                type_=sa.String(length=191),
+                existing_nullable=False
+            )
+            batch_op.alter_column(
+                'url',
+                existing_type=sa.String(length=767),
+                type_=sa.String(length=191),
+                existing_nullable=False
+            )
+    else:
+        # PostgreSQL and MySQL support direct ALTER COLUMN
+        op.alter_column(
+            'gateways',
+            'slug',
+            existing_type=sa.String(length=255),
+            type_=sa.String(length=191),
+            existing_nullable=False
+        )
+        op.alter_column(
+            'gateways',
+            'url',
+            existing_type=sa.String(length=767),
+            type_=sa.String(length=191),
+            existing_nullable=False
+        )
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # Get database dialect for dialect-specific operations
+    bind = op.get_bind()
+    dialect_name = bind.dialect.name
+
+    # SQLite requires batch operations for ALTER COLUMN
+    if dialect_name == 'sqlite':
+        with op.batch_alter_table('gateways', schema=None) as batch_op:
+            batch_op.alter_column(
+                'slug',
+                existing_type=sa.String(length=191),
+                type_=sa.String(length=255),
+                existing_nullable=False
+            )
+            batch_op.alter_column(
+                'url',
+                existing_type=sa.String(length=191),
+                type_=sa.String(length=767),
+                existing_nullable=False
+            )
+    else:
+        # PostgreSQL and MySQL support direct ALTER COLUMN
+        op.alter_column(
+            'gateways',
+            'slug',
+            existing_type=sa.String(length=191),
+            type_=sa.String(length=255),
+            existing_nullable=False
+        )
+        op.alter_column(
+            'gateways',
+            'url',
+            existing_type=sa.String(length=191),
+            type_=sa.String(length=767),
+            existing_nullable=False
+        )
diff --git a/mcpgateway/db.py b/mcpgateway/db.py
index 7dfa40800..c905a00a8 100644
--- a/mcpgateway/db.py
+++ b/mcpgateway/db.py
@@ -2430,8 +2430,8 @@ class Gateway(Base):
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, default=lambda: uuid.uuid4().hex)
     name: Mapped[str] = mapped_column(String(255), nullable=False)
-    slug: Mapped[str] = mapped_column(String(255), nullable=False)
-    url: Mapped[str] = mapped_column(String(767), nullable=False)
+    slug: Mapped[str] = mapped_column(String(191), nullable=False)
+    url: Mapped[str] = mapped_column(String(191), nullable=False)
     description: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
     transport: Mapped[str] = mapped_column(String(20), default="SSE")
     capabilities: Mapped[Dict[str, Any]] = mapped_column(JSON)
diff --git a/tests/unit/mcpgateway/test_translate_stdio_endpoint.py b/tests/unit/mcpgateway/test_translate_stdio_endpoint.py
index 4f08cdd9e..4ca7aaa7b 100644
--- a/tests/unit/mcpgateway/test_translate_stdio_endpoint.py
+++ b/tests/unit/mcpgateway/test_translate_stdio_endpoint.py
@@ -8,7 +8,6 @@
 
 Tests for StdIOEndpoint class modifications to support dynamic environment variables.
 """
-
 import sys
 import asyncio
 import pytest
@@ -256,15 +255,13 @@ async def test_multiple_env_vars(self, test_script):
         pubsub = _PubSub()
 
         env_vars = os.environ.copy()
-        env_vars.update(
-            {
-                "GITHUB_TOKEN": "github-token-123",
-                "TENANT_ID": "acme-corp",
-                "API_KEY": "api-key-456",
-                "ENVIRONMENT": "production",
-                "DEBUG": "false",
-            }
-        )
+        env_vars.update({
+            "GITHUB_TOKEN": "github-token-123",
+            "TENANT_ID": "acme-corp",
+            "API_KEY": "api-key-456",
+            "ENVIRONMENT": "production",
+            "DEBUG": "false",
+        })
 
         endpoint = StdIOEndpoint(f"{sys.executable} {test_script}", pubsub, env_vars)