diff --git a/amethyst/src/test/java/com/vitorpamplona/amethyst/service/okhttp/OnionUrlParseTest.kt b/amethyst/src/test/java/com/vitorpamplona/amethyst/service/okhttp/OnionUrlParseTest.kt
new file mode 100644
index 0000000000..8ad8cb8cc3
--- /dev/null
+++ b/amethyst/src/test/java/com/vitorpamplona/amethyst/service/okhttp/OnionUrlParseTest.kt
@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.service.okhttp
+
+import okhttp3.HttpUrl.Companion.toHttpUrl
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Test
+
+/**
+ * Verifies that OkHttp 5.x HttpUrl.toHttpUrl() accepts .onion pseudo-TLD hostnames.
+ *
+ * .onion is not an IANA-registered TLD (RFC 7686), so it may be rejected by strict
+ * domain validators. If toHttpUrl() rejects .onion URLs the entire OnionUrlRewriteInterceptor
+ * feature silently falls through to the clearnet address. This test documents and guards
+ * the actual OkHttp behavior so any upgrade that breaks .onion support is caught.
+ */
+class OnionUrlParseTest {
+    // A real Tor v3 .onion address (56 base32 chars + ".onion")
+    private val torV3Host = "vww6ybal4bd7szmgncyruucpgfkqahzddi37ktceo3ah7ngmcopnpyyd.onion"
+
+    @Test
+    fun torV3HttpUrl_parsesSuccessfully() {
+        val url = runCatching { "http://$torV3Host/".toHttpUrl() }.getOrNull()
+        assertNotNull(
+            "OkHttp must accept Tor v3 .onion hosts — if null, OnionUrlRewriteInterceptor is silently broken",
+            url,
+        )
+    }
+
+    @Test
+    fun torV3HttpUrl_hostIsPreserved() {
+        val url = "http://$torV3Host/".toHttpUrl()
+        assertEquals(torV3Host, url.host)
+    }
+
+    @Test
+    fun torV3HttpsUrl_parsesSuccessfully() {
+        val url = runCatching { "https://$torV3Host/".toHttpUrl() }.getOrNull()
+        assertNotNull(url)
+    }
+
+    @Test
+    fun torV3WithPort_parsesSuccessfully() {
+        val url = runCatching { "http://$torV3Host:8080/path".toHttpUrl() }.getOrNull()
+        assertNotNull(url)
+        assertEquals(8080, url?.port)
+    }
+
+    @Test
+    fun shortOnionLabel_parsesSuccessfully() {
+        // Shorter label (e.g. Tor v2-style) — also must be accepted
+        val url = runCatching { "http://relay.someservice.onion/".toHttpUrl() }.getOrNull()
+        assertNotNull(url)
+    }
+
+    // --- Regression: OnionUrlRewriteInterceptor scheme translation ---
+
+    @Test
+    fun wsOriginalWithHttpOnion_rewritesToWs() {
+        val onionUrlStr = "http://$torV3Host/"
+        val onionUrl = onionUrlStr.toHttpUrl()
+        val originalScheme = "ws"
+        val newScheme =
+            if (originalScheme == "ws" || originalScheme == "wss") {
+                if (onionUrl.scheme == "https") "wss" else "ws"
+            } else {
+                onionUrl.scheme
+            }
+        assertEquals("ws", newScheme)
+    }
+
+    @Test
+    fun wssOriginalWithHttpsOnion_rewritesToWss() {
+        val onionUrlStr = "https://$torV3Host/"
+        val onionUrl = onionUrlStr.toHttpUrl()
+        val originalScheme = "wss"
+        val newScheme =
+            if (originalScheme == "ws" || originalScheme == "wss") {
+                if (onionUrl.scheme == "https") "wss" else "ws"
+            } else {
+                onionUrl.scheme
+            }
+        assertEquals("wss", newScheme)
+    }
+}