evaluate()) that your tool dispatcher invokes.
What the SDK does
The SDK has three responsibilities, all of which run in your process without blocking your tool dispatch.Evaluator
evaluate() is sub-millisecond — it interprets your policy bundle against the tool call’s metadata and returns allow / deny synchronously, without a network round-trip on the hot path. Bundles are pre-compiled when received so regex evaluation is a constant-time operation per call.
Bundle cache
A background poller refreshes the bundle every 30 seconds. The bundle is kept in memory and used for every evaluation until the next poll succeeds. If Rubric is unreachable, the SDK keeps using the last-known-good bundle — your agent continues to enforce policy even during a network outage. The bundle is content-hashed; the poller sends?since=<hash> so unchanged bundles return 304 Not Modified instead of re-downloading. Incoming bundles are also checked for version monotonicity: a bundle whose bundleVersion is lower than the cached one, or whose builtAt is significantly older, is rejected to defeat rollback attempts.
Audit sink
Everyevaluate() enqueues an audit event into an in-memory queue. A background flush task batches events and ships them — default cadence is every second or 100 events, whichever comes first. Your code never waits on the network.
If the queue fills (default cap: 10,000 events) or repeated ship failures exhaust retries, events are dropped and a counter increments. The counters are surfaced through getStats() so your monitoring can alarm on silent drops.
Identity
On startup the SDK exchanges your enrollment token for a short-lived (60 minute) signed identity. A background task refreshes it ahead of expiry. The signed identity is what authenticates the bundle pulls and audit uploads — your enrollment token is only used at boot.What gets sent over the wire
The SDK makes three classes of HTTPS request:
That’s the whole egress surface. There is no telemetry, no anonymous usage reporting, and no other endpoint the SDK calls.
Trust model
Enrollment tokens are designed to be safe to commit to your deployment manifest. They can only register; if leaked the worst-case impact is “attacker creates an extra agent row in your org,” which is revocable from the dashboard.