diff --git a/caddytest/spec/http/request_header/spec.hurl b/caddytest/spec/http/request_header/spec.hurl
new file mode 100644
index 000000000..44e8c3d06
--- /dev/null
+++ b/caddytest/spec/http/request_header/spec.hurl
@@ -0,0 +1,190 @@
+# Configure Caddy with request_header directive
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	request_header X-Custom-Header "CustomValue"
+	respond "{header.X-Custom-Header}"
+}
+```
+
+# request_header adds headers to request
+GET https://localhost:9443
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "CustomValue"
+
+
+# Configure Caddy with request_header removing headers
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	request_header -User-Agent
+	respond "UA: {header.User-Agent}"
+}
+```
+
+# request_header can remove headers
+GET https://localhost:9443
+User-Agent: TestAgent/1.0
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "UA: "
+
+
+# Configure Caddy with request_header replacing headers
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	request_header Host "example.com"
+	respond "Host: {host}"
+}
+```
+
+# request_header can replace Host header
+GET https://localhost:9443
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Host: example.com"
+
+
+# Configure Caddy with request_header using placeholders
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	request_header X-Original-Path {path}
+	respond "Path: {header.X-Original-Path}"
+}
+```
+
+# request_header can use placeholders
+GET https://localhost:9443/test/path
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Path: /test/path"
+
+
+# Configure Caddy with conditional request_header
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	@api path /api/*
+	request_header @api X-API "true"
+	respond "API: {header.X-API}"
+}
+```
+
+# request_header applies conditionally based on matcher
+GET https://localhost:9443/api/test
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "API: true"
+
+
+# request_header doesn't apply when matcher doesn't match
+GET https://localhost:9443/other
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "API: "
+
+
+# Configure Caddy with multiple request_header operations
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+}
+localhost {
+	request_header X-First "1"
+	request_header X-Second "2"
+	request_header X-Third "3"
+	respond "{header.X-First},{header.X-Second},{header.X-Third}"
+}
+```
+
+# multiple request_header directives are applied
+GET https://localhost:9443
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "1,2,3"
+
+
+# Configure Caddy with request_header and reverse_proxy
+POST http://localhost:2019/load
+Content-Type: text/caddyfile
+```
+{
+	skip_install_trust
+	http_port     9080
+	https_port    9443
+	local_certs
+	debug
+}
+localhost {
+	request_header X-Custom-Header "Value"
+	reverse_proxy localhost:9450
+}
+http://localhost:9450 {
+	respond "{header.X-Custom-Header}"
+}
+```
+
+# request_header adds header before reverse_proxy
+GET https://localhost:9443
+[Options]
+insecure: true
+HTTP 200
+[Asserts]
+body == "Value"