AFFIXIO
Agent authorisation vs API keys
Agent authorisation vs API keys
API keys prove who called the API. Agent authorisation proves the autonomous action was permitted in context, with cryptographic evidence regulators can replay.
At a glance
- API keys
- Client authentication
- KYA gate
- Per-action authorisation
- Audit
- Signed Merkle proof
- OWASP
- Agentic Top 10 control
- Page
- /agent-authorisation/
- Reviewed
- 12 July 2026
API keys prove which client called an endpoint. Agent authorisation proves a specific autonomous action was permitted in context, with cryptographic evidence suitable for KYA and shadow AI governance.
Side-by-side comparison
| Dimension | Incumbent approach | AffixIO path |
|---|---|---|
| Scope | Whole API surface | Single action context |
| Agent identity | Often shared key | Agent-bound decision |
| Shadow AI risk | Key reuse hides agent | Deny by default outside policy |
| Evidence | Mutable logs | Signed allow or deny |
When Incumbent approach fits
- Simple service-to-service auth
- Human-initiated API calls only
- No autonomous tool execution
When AffixIO path fits
- MCP tool calls and agentic payments
- OWASP Agentic Top 10 controls
- Per-action audit for regulators
Decision guide
Most enterprises use both layers: incumbent tools for identity or operations, AffixIO for signed policy outcomes at the boundary with Merkle audit. The question is where the YES or NO is decided and what evidence regulators can replay.
Frequently asked questions
Replace OAuth?
No. AffixIO sits at the action boundary beneath auth.
Works with MCP?
Yes. Gate tool calls via MCP connector.
Replace OAuth?
No. AffixIO sits at the action boundary beneath auth.
Works with MCP?
Yes. Gate tool calls via MCP connector.
Shared API keys and shadow AI?
Shared keys hide which agent acted. KYA binds decisions to agent context.
Audit evidence?
Signed allow or deny with Merkle reference per action.