From c487e7eee507f18ccaa667f9adb982fa796d7289 Mon Sep 17 00:00:00 2001
From: Lasisi Ibrahim <113442282+ibrahimpelumi6142@users.noreply.github.com>
Date: Tue, 9 Dec 2025 23:25:38 +0000
Subject: [PATCH] =?UTF-8?q?=F0=9F=93=9D=20Add=20validation=20error=20examp?=
 =?UTF-8?q?le=20for=20Enum=20path=20parameters?=
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---
 docs/en/docs/tutorial/path-params.md | 34 ++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/docs/en/docs/tutorial/path-params.md b/docs/en/docs/tutorial/path-params.md
index 457cc2713..c9e2c3973 100644
--- a/docs/en/docs/tutorial/path-params.md
+++ b/docs/en/docs/tutorial/path-params.md
@@ -166,6 +166,40 @@ Because the available values for the *path parameter* are predefined, the intera
 
 <img src="/img/tutorial/path-params/image03.png">
 
+### Common Validation Errors with Enums { #enum-validation-errors }
+
+When using an `Enum` for a path parameter, FastAPI will validate the value automatically.
+
+For example, if your `ModelName` enum only allows:
+
+- `"alexnet"`
+- `"resnet"`
+- `"lenet"`
+
+And the client sends an invalid value:
+
+```
+GET /models/vgg16
+```
+
+FastAPI returns a clear validation error:
+
+```
+{
+  "detail": [
+    {
+      "type": "enum",
+      "loc": ["path", "model_name"],
+      "msg": "Input should be 'alexnet', 'resnet' or 'lenet'",
+      "input": "vgg16"
+    }
+  ]
+}
+
+```
+
+This helps catch invalid requests before they reach your logic and keeps your API behavior predictable.
+
 ### Working with Python *enumerations* { #working-with-python-enumerations }
 
 The value of the *path parameter* will be an *enumeration member*.