Capability Tokens: Real Security for AI Agents

Most agent frameworks have a dirty secret: agents run with God-mode permissions. They can read any file, call any API, access any database. The agent is one hallucination away from deleting your production database or leaking sensitive data to an external API.

This isn't a theoretical risk. It's a certainty at scale. If you run enough agents long enough, one of them will do something catastrophically wrong. The question is whether your infrastructure limits the blast radius.

Capability-Based Security

AitherOS uses capability tokens — a security model borrowed from operating systems research. Instead of giving an agent broad permissions and hoping for the best, each agent receives a signed token that lists exactly what it can do:

• Service access — Which AitherOS services the agent can call
• Memory scope — Which memory tiers and namespaces the agent can read/write
• Tool permissions — Which tools (file system, web, code execution) are available
• Rate limits — Maximum requests per minute to prevent runaway loops
• TTL — Token expiration time. Tokens rotate automatically.

Tokens are HMAC-signed by AitherSecrets, so they can't be forged or tampered with. Every service validates the token before processing a request. If the token doesn't grant access, the request is rejected — no exceptions.

Defense in Depth

Capability tokens are just one layer. AitherOS also runs AitherInspector for DLP (Data Loss Prevention) scanning — checking outbound data for sensitive content like credentials, PII, or proprietary code. Even if an agent has permission to make external calls, the DLP layer ensures it can't exfiltrate sensitive data.

This is what real agent security looks like. Not a disclaimer in the docs. Not a “use at your own risk” warning. Actual, enforced, cryptographic security boundaries.