Modern edge AI systems rely on dynamic, multi-stage pipelines vulnerable to adversarial attacks. Existing attacks primarily target static tasks and lack adaptability to these complex environments. We propose Hydra, an adversarial attack framework for AI-driven video streaming and edge security services. Hydra integrates three innovations: Multi-Stage Service Disruption (MSSD) that coherently misleads successive pipeline components, Resource-Aware Transferability Enhancement (RATE) for effective attacks under edge constraints, and Meta-Reinforcement Learning for Adaptive Perturbation (MetaRAP) that dynamically tunes attack parameters based on real-time system states. Evaluations on a multimodal medical RAG system demonstrate Hydra’s superior efficacy, achieving up to 75% ASR against specialized retrievers at 𝜖=8/255, a 12% absolute improvement over baselines. Hydra also exhibits strong transferability, defense robustness, and a favorable efficiency trade-off, requiring only 2.1 seconds per adversarial example. This work highlights a potent threat to edge intelligence services, urging development of robust multi-stage defenses.

Large language model (LLM) agents increasingly rely on function calling to act across multi-turn interactions, but compact models remain brittle when tool availability, required parameters, and dialogue constraints change over time. Existing synthetic tool-use data often broadens coverage without targeting the recurring failures of a specific model. We present FUSE, a failure-guided refinement approach that uses the model’s own function-calling errors to synthesize harder training scenarios and then emphasizes difficult examples during supervised fine-tuning. This data-centric design turns diagnostic failures into targeted training signal while remaining simple to apply with standard offline fine-tuning. Experiments on BFCLv3 show that FUSE substantially improves a compact Qwen3-based model across standard and stress categories, including missing functions, missing parameters, and long-context interactions. Evaluation on BFCLv4 provides initial evidence that the same refinement strategy can transfer to selected agentic function-calling tasks.