Silent Failures in Agent-Tool Interaction: An Audit of ToolUniverse SpeakerMem-R1: Speaker-Centered Dual-Track Memory for Multi-Party Dialogue Backdoors Leave Structural Traces: FedMAST for Backdoor Detection and Containment in Federated Learning Hard Negatives Reveal What Easy Negatives Hide: Cross-Lingual Harmfulness Representations Degrade with Resource Tier Under Hard Negatives QuantWM: Temporally Consistent 2-Bit KV Cache Quantization for World Models and Video Generation