An AI product data flow diagram for a buyer review should show where customer data enters, every place it is stored, each model call and its provider, trust boundaries, what is logged, and where data exits or is deleted. One page, labeled in plain words, usually answers most reviewer questions before they are asked.
What reviewers look for
A reviewer is trying to answer: where does our data go, who touches it, and what happens if one component is compromised? A good diagram answers those without a meeting. OWASP lists sensitive information disclosure (LLM02:2025) and vector and embedding weaknesses (LLM08:2025) among the risks for LLM apps, so those flows deserve explicit boxes.
Elements to include
| Element | What to show |
|---|---|
| Entry points | Web app, API, file uploads, connectors |
| Data stores | Primary database, object storage, vector store, caches |
| Model calls | Which provider or self-hosted runtime, and what data is sent |
| Agent tools | External systems an agent can read or change |
| Trust boundaries | Lines between customer, your services, and third parties |
| Logs | What prompts, outputs, and tool calls are recorded |
| Retention and deletion | How long data stays and how it is removed |
| Tenant separation | Where customers are separated and how |
Mark the boundaries
A trust boundary is a line where data moves between parties or privilege levels, for example from your service to a model provider. Draw them as visible lines and label what crosses. See trust boundaries in a data flow diagram.
Be specific about the model call
Show what goes into a prompt: user text only, retrieved documents, tool results, system prompt. Say whether the provider retains it and whether it trains on it, and point to the contract clause. Link to your subprocessor list.
Keep it honest
Do not draw the target architecture. Draw what runs today, with a date and an owner. If a control is planned, label it as planned. A diagram that overstates reality is worse than none, because reviewers compare it with your answers.
Update it with the product
Review the diagram whenever you add a model provider, data store, or agent tool. Add it to your change checklist.
A short note on Safeguard
Safeguard offers asset discovery and SBOM generation, which help keep the component list behind a diagram accurate. Try a free scan at gold.safeguard.sh/scan.
Quick check
Should the diagram show vendor names?
Yes for providers that handle customer data, since reviewers need them for subprocessor checks.
How detailed should it be?
One page for the overview. Keep deeper component diagrams for follow up questions.
Sources
Last reviewed: 19 October 2026.
