Free plan available. hark pro² at $20/month with 2× more usage. hark pro³ at $100/month with 10× more usage. All features available in all plans; upgrading increases usage capacity.
Per-execution pricing: one fee per execution that returns proof, charged only when proof comes back. Failed or cancelled runs cost nothing. Planning and approvals are free.
Key features
Persistent memory to tailor responses based on shared context
Computer use agent for browsing, research, and web tasks
End-to-end encryption for data security
Action Buttons for prioritized task completion
Email management and sorting
Flight booking and travel planning
Food ordering integration
Appointment booking and healthcare search
Expense auditing and savings recommendations
Boundary approval system for controlled execution
Checkpoint-based resumable execution
Verifiable proof of completion
Composable proof for multi-agent workflows
Per-execution pricing model
Integration with multiple agent frameworks
What makes it different
Operates its own secure computer with full browser for independent task execution
End-to-end encryption vault for sensitive data protection
User approval required before performing sensitive actions
All features available across free and paid tiers
Pay only for verified results, not for attempts or planning
Human-approved boundaries ensure agent actions stay within limits
Interruptible checkpoints allow pausing and resuming executions
Proof is built into results for auditability and composability
Hark
Kairos