diff --git a/AGENTS.md b/AGENTS.md
index 7d30cc1..c05f476 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -2,8 +2,22 @@
 
 ## Code and tooling
 
-- All code must remain compatible with PHP 7.4, and PHPStan and PHP-CS-Fixer
-  must be run against PHP 7.4.
+- All code must remain compatible with PHP 7.4. Run PHPStan and PHP-CS-Fixer
+  only under a PHP 7.4.x runtime; never run either tool under any other PHP
+  major.minor version.
+- Use fully qualified `#[\SensitiveParameter]` on concrete executable
+  parameters when their established role normally carries a secret,
+  credential-bearing aggregate, or confidential Guzzle-owned container, and
+  the active frame can throw or invoke throwing code.
+- Repeat the attribute on every qualifying owned caller, callee, concrete trait
+  method, and closure parameter. Do not add it to interfaces, abstract-only
+  declarations, pure/no-realistic-throw helpers, assignment-only sites,
+  arbitrary generic payloads, or completed non-recoverable derivatives.
+- For PHP 7.4 compatibility, put `#[\SensitiveParameter]` on its own line and
+  the parameter on the following line, expand the complete parameter list, and
+  never add a comma after the final parameter. Native trace redaction starts on
+  PHP 8.2 and does not redact logs, messages, properties, wire traffic, captured
+  variables, return values, or the separate backtrace `$this`/`object`.
 - Always pass an explicit character list to `trim()`, `ltrim()`, and `rtrim()`;
   never rely on the default characters.
 - Handle `preg_*` engine failures: when the result is used as data, test for
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 96a86a1..e20471b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@
 - Added a `guzzle-server/stall-brief` endpoint that stalls mid-body for 1.5s, then completes
 - Added `Server::enqueueRawBytes()` to queue verbatim-byte responses that bypass Node's HTTP handling
 - Inline Digest auth so secure endpoints avoid optional `http-auth` and no-qop is deterministic
+- Hide queued and received raw HTTP records in stack traces on PHP 8.2+
 
 ## 0.7.0 - 2026-07-16
 
diff --git a/UPGRADING.md b/UPGRADING.md
index 0ff32b7..d95fb28 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -70,3 +70,14 @@ if (!is_int($validatedPort)) {
 Server::$port = $validatedPort;
 Server::$url = sprintf('http://127.0.0.1:%d/', Server::$port);
 ```
+
+#### Sensitive Stack Trace Arguments
+
+Queued and received raw HTTP records are marked with
+`#[\SensitiveParameter]`. PHP 8.2 and later replace those arguments in stack
+traces with `SensitiveParameterValue`. PHP 7.4 through 8.1 do not redact trace
+arguments.
+
+This does not redact the Node server log, other logs, exception messages,
+object properties, wire traffic, captured variables, return values, user
+callbacks, or the separate executing object in an explicit backtrace.
diff --git a/composer.json b/composer.json
index 24151c5..1f9546d 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,8 @@
         "php": "^7.4 || ^8.0",
         "guzzlehttp/guzzle": "^8.0@dev",
         "guzzlehttp/psr7": "^3.0@dev",
-        "symfony/polyfill-php80": "^1.25"
+        "symfony/polyfill-php80": "^1.25",
+        "symfony/polyfill-php82": "^1.27"
     },
     "require-dev": {
         "bamarni/composer-bin-plugin": "^1.8.2",
diff --git a/src/Server.php b/src/Server.php
index e8d5279..2e2131a 100644
--- a/src/Server.php
+++ b/src/Server.php
@@ -73,8 +73,10 @@ public static function flush(): ResponseInterface
      *
      * @throws InvalidArgumentException
      */
-    public static function enqueue($responses): void
-    {
+    public static function enqueue(
+        #[\SensitiveParameter]
+        $responses
+    ): void {
         if ($responses instanceof ResponseInterface) {
             $responses = [$responses];
         }
@@ -114,8 +116,14 @@ public static function enqueue($responses): void
      *
      * @throws \GuzzleHttp\Exception\GuzzleException
      */
-    public static function enqueueRaw($statusCode, string $reasonPhrase, array $headers, ?string $body): void
-    {
+    public static function enqueueRaw(
+        $statusCode,
+        string $reasonPhrase,
+        #[\SensitiveParameter]
+        array $headers,
+        #[\SensitiveParameter]
+        ?string $body
+    ): void {
         $data = [
             [
                 'status' => (string) $statusCode,
@@ -139,8 +147,10 @@ public static function enqueueRaw($statusCode, string $reasonPhrase, array $head
      *
      * @throws \GuzzleHttp\Exception\GuzzleException
      */
-    public static function enqueueRawBytes(string $bytes): void
-    {
+    public static function enqueueRawBytes(
+        #[\SensitiveParameter]
+        string $bytes
+    ): void {
         self::getClient()->request('PUT', 'guzzle-server/responses', [
             'json' => [
                 [
@@ -176,7 +186,10 @@ public static function received(): array
         }
 
         return \array_map(
-            static function ($message): RequestInterface {
+            static function (
+                #[\SensitiveParameter]
+                $message
+            ): RequestInterface {
                 if (!\is_array($message)) {
                     throw new \RuntimeException('Expected each received request from node.js server to be an array');
                 }