ProvenanceGuard checks whether the citation belongs to the claim
Multiverse Computing's approach preserves tool-source identities to detect facts attributed to the wrong evidence.
Context breaks when an agent merges tool outputs and loses track of which source supplied each fact. ProvenanceGuard targets the resulting attribution error: a statement has support somewhere, but the answer credits the wrong source.
The authors illustrate this with a refund condition found in a policy document but attributed to an account record. Searching the combined evidence for that condition can confirm its existence while missing the incorrect citation.
ProvenanceGuard runs after answer generation. It reads the MCP execution trace, retains source identifiers, extracts claims and checks both support and attribution. The reported experiments use local components; replacing them requires fresh testing and calibration. The study also reports unnecessary blocks and difficulty identifying exact sources when several look similar.
My architectural recommendation is to retain the connection between claims and individual tool outputs from the outset. A review stage needs that record to inspect attribution rather than merely search for matching facts.
The remaining operational decision is which mismatches require human review and which can receive an automatically repaired answer that is checked again.
Source: Antonio Tiene and colleagues, Multiverse Computing, ProvenanceGuard introduction, published September 29, 2026.