Single execution vs Project Bundle
Two paths. Pick the one that matches what you actually need to prove.
NexArt supports two practical verification paths. Most teams start with single-execution CERs and only adopt Project Bundles when their workflows become multi-step or multi-agent. Both paths produce independently verifiable evidence.
Single execution
One execution, one CER.
- A single model call, tool call, or decision.
- One Certified Execution Record per call.
- Verifiable on its own at verify.nexart.io.
- Enough for most integrations.
- You run a single-shot prompt or classifier.
- You need proof per API response.
- Each decision is independently meaningful.
- You are starting out and want the simplest surface.
Project Bundle
Many certified steps, one projectHash.
- A multi-step workflow sealed as one artifact.
- Each step is a CER; the bundle binds them together.
- One projectHash verifies the entire run.
- Suited to agent loops and tool chains.
- You run agentic or multi-step pipelines.
- You need to prove a sequence, not just a step.
- Multiple models or tools cooperate on one task.
- Auditors need the full chain in one artifact.
How to choose
If a single call captures the decision you care about, a single CER is enough. If the decision only makes sense as a sequence, plan, retrieve, call, summarize, act, then a Project Bundle is the right artifact. You can mix both in the same system.
What stays the same
- Both paths produce tamper-evident records.
- Both can be verified publicly, without an account.
- Both support redacted verification for privacy-sensitive content.
- Both use the same cryptographic primitives (SHA-256 sealing, Ed25519 attestation).
What changes
| Dimension | Single CER | Project Bundle |
|---|---|---|
| Scope | One execution | Multi-step run |
| Identifier | certificate hash | projectHash + per-step hashes |
| Verification URL | /c/:hash or /e/:executionId | /p/:projectHash |
| Typical user | Builders shipping single-call features | Teams running agents and pipelines |
| Overhead | Lowest | Slightly higher, one bundle per run |
Project Bundles are an expansion, not a default
You do not need Project Bundles to get value from NexArt. A single CER is already a verifiable artifact a third party can check without trusting you. Project Bundles exist because real agent systems are not a single call, and regulators, auditors, and customers increasingly want evidence of the full sequence, not just the final answer.