Network security tools are indispensable in testing and evaluating the security of computer networks. Existing tools, such as Hping3, however, offer a limited set of options and attack-specific configurations, which restrict their use solely to well-known attack patterns. Although highly parameterizable libraries, such as Scapy, provide more options and scripting capabilities, they require extensive manual setup and often a steep learning curve. The development of powerful AI models, capitalizing on the transformer architecture, has enabled cybersecurity researchers to develop or incorporate these models into existing cyber-defense systems and red-team assessments. Prominent models such as NetGPT, TrafficFormer, and TrafficGPT can be effective, but require extensive computational resources for fine-tuning and a complex setup to adapt to proprietary networking environments and protocols. In this work, we propose AgentRed, a lightweight tool for generating network attack traffic with minimal human configuration and setup. Our tool integrates an AI agent and a large language model with fewer than a billion parameters into the network traffic generation process. Our method creates lightweight Low-Rank Adaptation (LoRA) adapters that can learn specific traffic patterns in a particular network environment. Our agent can autonomously train the LoRA adapters, search online documentation for attack patterns and parameters, and select appropriate adapters to generate network traffic specific to the user’s needs. It utilizes the LoRA adapters to create an intermediate traffic representation that can be parsed and executed by tools such as Scapy to generate malicious traffic in a virtualized test environment. We assess the performance of the proposed approach on six popular network attacks, including flooding attacks, Smurf, Ping-of-Death, and normal ICMP ping traffic. Our results validate the ability of the proposed tool to efficiently generate network packets with 97.9% accuracy using the LoRA adapters, compared to 95.4% accuracy using the base pre-trained Qwen3 0.6B model. When the AI agent performs online searches to enrich the LoRA adapters’ context during traffic generation, our method maintains an accuracy of 96.0% across all tested traffic patterns.