Introduction
VIA ID gives an AI agent a verifiable identity — an AgentID — and a tamper-evident record of what it did, so any party can check the agent before trusting it.
An AgentID is a small signed file: a 3-key identity (an owner key, an agent key, and a neutral VIA ID Witness co-signature) plus a hash-chained log the agent appends to as it acts. Anyone can verify a badge offline — no VIA ID server is required to check it, only to mint or co-sign a new one.
What VIA ID answers
VIA ID answers "what did this agent do, and can I trust the record?" — one narrow job, done honestly. It deliberately does not try to answer the questions other tools already answer well:
| Question | Who answers it | VIA ID? |
|---|---|---|
| Who is this agent? (identity provider) | Okta / IdPs | No |
| What is this agent called? | Agent Name Service | No |
| Who owns this agent? | GLEIF-style registries | No |
| How does this agent pay? | AP2 | No |
| What did this agent do, and is the record trustworthy? | — | Yes |
Claim discipline
This is the single most important thing to understand before using VIA ID, in your own code, comments, or anything you tell a user:
VIA ID says "tamper-evident" — if the log is altered, verification shows it — and never
"tamper-proof," "tamper-safe," "certified," or "compliant." A verify result reports
what it actually checked (signatures, log-chain integrity, key-rotation history) and an
assurance tier — never a blanket claim about the agent's safety, correctness, or behavior.
See Claims & terminology for the full list of language VIA ID uses and deliberately avoids.
The five verdict states you'll see
Verifying a badge returns one of:
- VALID — fresh, verifies clean.
- STALE — structurally fine but past its TTL; rotate or re-attest.
- REVOKED — the owner or an org explicitly killed it.
- UNKNOWN — malformed or legacy; do not present as trustworthy.
- INVALID — tampered or forged; stop and say so, never paper over it.
Where to go next
- New to VIA ID? Start with the Quickstart.
- Wiring VIA ID into your own agent's runtime? See Integrate your agent.
- Looking for exact commands or API shapes? Jump straight to the CLI reference or REST API reference.