Encryption keys you can revoke.
Your agents accumulate real work: files, memory, conversations. With customer-managed keys, that data is sealed under a key that lives in your KMS. Revoke it, and the data can no longer be decrypted - by Karta, or by anyone.
A layer of control, not a fix for a gap.
Everything on Karta is already encrypted at rest under platform-managed keys. Customer-managed keys add the thing platform encryption cannot give you: control. Your key, in your KMS, under your IAM policy, with every decrypt request visible in your own KMS logs.
Envelope encryption, keyed from your KMS.
Your KMS key wraps a per-tenant key, which derives per-store data keys - workspaces and conversations sealed separately. Your key material never leaves your KMS; Karta requests operations against it, and your KMS records each one.
your KMS key ─▶ per-tenant key ─▶ per-store data keys ─▶ workspaces · conversations
The kill switch
Revoking access to your key ends Karta's ability to decrypt the data it protects. That is the point: offboarding, incident response, and jurisdiction disputes all reduce to an IAM action you take in your own account.
Crypto-shredding
Deleting a tenant's keys makes its stored data permanently unreadable without touching every copy - deletion as a cryptographic guarantee rather than a cleanup job.
Per-tenant boundaries
Keys are scoped per tenant, so a multi-tenant agent product can offer each of its customers their own cryptographic boundary.
Your audit trail, doubled
Karta's audit log records access to the data; your KMS logs record every use of the key. Two independent trails that have to agree.
Scope, honestly.
Covered
- · Durable workspace content: files, memory, artifacts
- · Conversation history
Not covered
- · Account, agent, and session metadata
- · Usage and billing records
- · Operational logs
Should you use it? Only if you have the requirement. Customer-managed keys add real operational duties on your side - key availability is yours to guarantee, and revocation is final by design. Teams without a regulatory or contractual driver are better served by the platform default. If you have the driver, this is the mechanism that satisfies it, and we configure it with you as a design partner - AWS KMS first.