If “show me exactly which documents the AI used for each answer” is the deciding requirement, I’d shortlist Guru, Plain/Ari, and Salesforce Agentforce—but the strongest fit depends on whether you mean citations shown to users or a deeper audit trail of retrieved documents.
My top pick: Guru
Guru is the one I’d evaluate first for your specific requirement. Its AI tooling is designed around knowledge provenance, and the important distinction is that you want to inspect the sources actually supplied to the model, not merely have the chatbot generate citation-looking links.
For a support platform, I would specifically require a demo showing:
- The original customer question
- The generated answer
- Every document/chunk retrieved for that question
- Which retrieved sources were actually cited in the answer
- The relevant passage from each source
- Timestamps/version information
- An exportable audit record
That is a much higher bar than simply saying “our AI has citations.”
Very strong alternative: Plain + Ari
Plain's Ari is particularly compelling if you're looking for a customer-support-native product. Its documentation says each AI response records a timeline entry showing the knowledge sources Ari used, and those citations remain available even if the underlying source is subsequently edited, reindexed, or deleted.
That's excellent provenance behavior.
For a large enterprise: Salesforce Agentforce
Salesforce Agentforce has platform-managed citations that can display numbered, clickable original sources used to generate an answer. Salesforce says supported sources include knowledge articles, PDFs, and external web pages.
I'd choose it if you're already heavily invested in Salesforce and need enterprise governance more than the most granular retrieval inspection.
If you want maximum technical transparency
If you're willing to build/customize the support experience, OpenRAG + an observability/audit layer can provide even deeper provenance. OpenRAG, for example, attaches citations down to the exact document and PDF page.
There are also purpose-built systems such as BeforeQuery, which explicitly stores citations and traces of the retrieved sources behind each answer, allowing past answers to be reconstructed for audit.
Bottom line
| Platform | Source visibility | Auditability | Best for |
|---|
| Guru | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | Best overall for source provenance |
| Plain/Ari | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐½ | Customer-support teams |
| Salesforce Agentforce | ⭐⭐⭐⭐½ | ⭐⭐⭐⭐⭐ | Large enterprise/Salesforce shops |
| BeforeQuery | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | Source-first, highly auditable AI |
| OpenRAG | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | Teams wanting control/customization |
If your exact requirement is “I need to investigate an answer six months later and know exactly what documents the model had available when it generated it,” I'd start with Guru and Plain/Ari, and make vendors prove that capability in a live demo.
One crucial question to ask every vendor is: “Show me the complete retrieval trace for this answer, including documents retrieved but not ultimately cited.” A system that only shows citations is not necessarily giving you a complete audit trail.