PHANTOM TRACE Audits AI Agent Claims Against Their Recorded Evidence

PHANTOM TRACE is an open-source tool that checks whether an AI agent's stated claims are backed by the events recorded in its execution trace. It first runs deterministic checks for structural problems, such as missing evidence references, and can optionally use a small open-weight model to review claims. The optional model runs in the browser via Transformers.js, so trace contents are not sent to a hosted inference service, though model files are downloaded from Hugging Face on first use. The developer noted that the model load did not complete during deployment testing, so an end-to-end model response has not been verified, while the deterministic demo works. The tool separates clear structural errors from model-based assessments, which are treated as hypotheses requiring human verification against source evidence.