Relay Agents vs Sierra: 2026 comparison
Human-in-the-loop workflow agents that connect 100+ apps with approvals.
Relay Agents vs Sierra — specs
| Spec | Relay Agents | Sierra |
|---|---|---|
| Agent Rank | 72 / 100 (A) | 78 / 100 (A) |
| Autonomy | Semi-autonomous | Autonomous |
| Pricing | Freemium · from $18 | Subscription · Free tier |
| Open source | No | No |
| Capabilities | Tool use, Memory | Voice, Tool use, Memory, RAG |
| Integrations | 4 apps | 3 apps |
| Verified | Verified | Verified |
| Released | Mar 2025 | Feb 2025 |
Agent Rank breakdown
- Autonomy fit
- 8
- Capabilities
- 4
- Integrations
- 8
- Pricing value
- 8
- Polish & maturity
- 5
- Verifiability
- 10
Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?
- Autonomy fit
- 9
- Capabilities
- 8
- Integrations
- 6
- Pricing value
- 9
- Polish & maturity
- 5
- Verifiability
- 10
Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?
Pros & cons
- +Strongest human-in-the-loop pattern of any no-code agent
- +Connects 100+ apps with conditional logic and approval gates
- +Free tier is real — not a trial in disguise
- −AI features are lighter than purpose-built agent platforms
- −Per-seat pricing scales fast for larger teams
- −No native phone / voice support
- +Best-in-class for branded customer-facing agents (voice + chat parity)
- +Concierge onboarding from one of the strongest teams in AI
- +Indistinguishable-from-human quality in tier-1 deployments
- −Enterprise-only pricing — typical contracts $150–500k/year
- −Deployment is white-glove, not SaaS — multi-week setup
- −Overkill for SMB or mid-market support volumes
Pricing
- +200 runs/mo
- +All app integrations
- +2,000 runs/mo
- +Multi-step approvals
- +Conditional branching
- +Shared workflows
- +Audit log
- +Role-based access
- +Voice + chat
- +Custom persona
- +White-glove implementation
- +SOC 2 II + HIPAA option
Which one should you pick?
Pick Relay Agents if its specific capabilities (Tool use, Memory) match what you need.
Try Relay Agents →Pick Sierra if cost is the main constraint or if you want the highest autonomy and the verification loop is in place.
Try Sierra →Affiliate links. We may earn a commission at no extra cost to you.
Frequently asked
Should I pick Relay Agents or Sierra in 2026?+
Pick Relay Agents if its specific capabilities (Tool use, Memory) match what you need. Pick Sierra if cost is the main constraint or if you want the highest autonomy and the verification loop is in place. Most working teams running both can use Relay Agents for primary work and Sierra for the workflows where its specific strengths matter.
What's the price difference between Relay Agents and Sierra?+
Relay Agents starts at Freemium · from $18; Sierra starts at Subscription · Free tier. Sierra is the cheaper entry option. For team deployments the TCO can differ — use the AI Agent Rank TCO calculator for your specific volume.
Which is more autonomous, Relay Agents or Sierra?+
Sierra is the more autonomous of the two (Autonomous vs Semi-autonomous). Higher autonomy ships throughput faster but requires verification loops in place — see our autonomous-vs-copilot framing for when each tier wins.