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Adept vs Sierra: 2026 comparison

Browser-driving AI agent — completes multi-step workflows on real web apps the way a human would.

⚙️OpsAutonomousSubscription
BrowserTool useMemoryVision

Branded customer-facing agents from the founders of Salesforce + Google.

🎧SupportAutonomousSubscription
VoiceTool useMemoryRAG

Adept vs Sierra — specs

SpecAdeptSierra
Agent Rank67 / 100 (B)78 / 100 (A)
AutonomyAutonomousAutonomous
PricingSubscription · Free tierSubscription · Free tier
Open sourceNoNo
CapabilitiesBrowser, Tool use, Memory, VisionVoice, Tool use, Memory, RAG
Integrations3 apps3 apps
VerifiedVerified
ReleasedApr 2025Feb 2025

Categories: AdeptOps · SierraSupport

Agent Rank breakdown

Adept
Agent Rank
67/ 100
BB-tier
Autonomy fit
9
Capabilities
8
Integrations
4
Pricing value
9
Polish & maturity
4
Verifiability
6

Auto-computed from autonomy, capabilities, integrations, pricing, maturity and editorial verification. Updated every deploy. How is this computed?

Sierra
Agent Rank
78/ 100
AA-tier
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

Adept
Pros
  • +Pioneering work on UI-driven browser agents — strong research lineage
  • +Best for fully-autonomous, multi-step workflows that cross web apps
  • +Foundation models tuned specifically for browser action prediction
Cons
  • Not generally available — enterprise pilots only as of mid-2026
  • Pricing not public
  • Reliability on long-tail UIs still a work in progress
Sierra
Pros
  • +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
Cons
  • 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

Adept
Enterprise preview
Custom
Enterprise pilots
  • +Browser-driving agent
  • +Custom workflow training
  • +Dedicated research-eng support
Sierra
Recommended
Branded agent
Custom
Enterprise
  • +Voice + chat
  • +Custom persona
  • +White-glove implementation
  • +SOC 2 II + HIPAA option

Which one should you pick?

Adept

Pick Adept if its specific capabilities (Browser, Tool use) match what you need.

Try Adept →
Sierra

Pick Sierra if you want a vendor we've verified for accessibility and pricing accuracy.

Try Sierra →

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Frequently asked

Should I pick Adept or Sierra in 2026?+

Pick Adept if its specific capabilities (Browser, Tool use) match what you need. Pick Sierra if you want a vendor we've verified for accessibility and pricing accuracy. Most working teams running both can use Adept for primary work and Sierra for the workflows where its specific strengths matter.

What's the price difference between Adept and Sierra?+

Both Adept and Sierra start in the same pricing range (Subscription · Free tier vs Subscription · Free tier). Total cost of ownership depends on your team size and volume — see the TCO calculator for your specific math.

Which is more autonomous, Adept or Sierra?+

Both Adept and Sierra are Autonomous agents — neither has a meaningful autonomy advantage over the other. The decision should hinge on capabilities and pricing instead.

Want the real monthly cost at your volume? Run the TCO calculator →
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