quarkusio/quarkus · error · DeploymentException

Unable to determine the client name from the parameter at po

Error message

Unable to determine the client name from the parameter at position ${position} in method ${class}#${method}() - compile the class with debug info enabled (-g) or parameter names recorded (-parameters), or use GrpcClient#value() to specify the service name

What it means

When @GrpcClient is placed on a method parameter (CDI initializer) without an explicit value, Quarkus derives the client name from the parameter name, which requires debug info (-g) or -parameters compiler flags. When the parameter name is not recorded in the bytecode, deployment fails with this error.

Source

Thrown at extensions/grpc/deployment/src/main/java/io/quarkus/grpc/deployment/GrpcClientProcessor.java:166

        for (InjectionPointInfo injectionPoint : beanDiscovery.getInjectionPoints()) {
            AnnotationInstance clientAnnotation = injectionPoint.getRequiredQualifier(GrpcDotNames.GRPC_CLIENT);
            if (clientAnnotation == null) {
                continue;
            }
            Set<String> registeredInterceptors = getRegisteredInterceptors(injectionPoint);

            String clientName;
            AnnotationValue clientNameValue = clientAnnotation.value();
            if (clientNameValue == null || clientNameValue.asString().equals(GrpcClient.ELEMENT_NAME)) {
                // Determine the service name from the annotated element
                if (clientAnnotation.target().kind() == Kind.FIELD) {
                    clientName = clientAnnotation.target().asField().name();
                } else if (clientAnnotation.target().kind() == Kind.METHOD_PARAMETER) {
                    MethodParameterInfo param = clientAnnotation.target().asMethodParameter();
                    clientName = param.method().parameterName(param.position());
                    if (clientName == null) {
                        throw new DeploymentException("Unable to determine the client name from the parameter at position "
                                + param.position()
                                + " in method "
                                + param.method().declaringClass().name() + "#" + param.method().name()
                                + "() - compile the class with debug info enabled (-g) or parameter names recorded (-parameters), or use GrpcClient#value() to specify the service name");
                    }
                } else {
                    // This should never happen because @GrpcClient has @Target({ FIELD, PARAMETER })
                    throw new IllegalStateException(clientAnnotation + " may not be declared at " + clientAnnotation.target());
                }
            } else {
                clientName = clientNameValue.asString();
            }

            if (clientName.trim().isEmpty()) {
                throw new DeploymentException(
                        "Invalid @GrpcClient `" + injectionPoint.getTargetInfo() + "` - client name cannot be empty");
            }

View on GitHub (pinned to e1c734241f)

Solutions

1. Add value to the annotation: @GrpcClient("service-name") on the parameter
2. Compile with parameter names: set <parameters>true</parameters> (maven.compiler.parameters) or enable -g debug info
3. Set maven-compiler-plugin <debug>true</debug> and <debuglevel>names</debuglevel>
4. Move the injection to a field, where the field name is always available

Example fix

// before
@Inject
void setGreeter(@GrpcClient Greeter greeter) { ... }

// after
@Inject
void setGreeter(@GrpcClient("hello-service") Greeter greeter) { ... }

// annotate parameters explicitly instead of relying on -parameters
void setGreeter(@GrpcClient("hello-service") Greeter greeter) { ... }
// or verify build config: maven.compiler.parameters=true

When it happens

Trigger: A method like void setGreeter(@GrpcClient Greeter g) has no name recorded for the parameter at the given position: the class was compiled without -g and without -parameters, and @GrpcClient.value() was not set.

Common situations: Maven/Gradle builds that strip debug info (maven.compiler.debug=false); Kotlin/other-language compilation without parameter name retention; annotated methods in dependencies compiled elsewhere; IDE-compiled classes without -parameters.

Related errors

• Unable to derive the service interface for the generated Mut
• ${clientAnnotation} may not be declared at ${target}
• Invalid @GrpcClient `${targetInfo}` - client name cannot be
• A gRPC service injection is missing the @GrpcClient qualifie
• A gRPC service injection is missing the @GrpcClient qualifie

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/6c02f37cd0c0f5fa. Report an issue: GitHub.