Forrester Wave Leader 2026 — enterprise voice and chat agent platform (now NiCE Cognigy).
ツール利用音声メモリRAG
Demo · hover to playPolyAI vs Sierrawhich AI support agent should you pick in 2026?
Enterprise voice assistants for call centers — natural conversations that resolve customer calls.
VoiceTool useMemoryRAG
PolyAI vs Sierra — specs
| Spec | PolyAI | Sierra |
|---|---|---|
| Agent Rank | 73 / 100 (A) | 78 / 100 (A) |
| Autonomy | Autonomous | Autonomous |
| Pricing | Subscription · Free tier | Subscription · Free tier |
| Open source | No | No |
| Capabilities | Voice, Tool use, Memory, RAG | Voice, Tool use, Memory, RAG |
| Integrations | 3 apps | 3 apps |
| Verified | Verified | Verified |
| Released | Sep 2024 | Feb 2025 |
Agent Rank breakdown
PolyAI
Agent Rank
73/ 100
- 自律性
- 9
- 機能
- 8
- 連携
- 4
- 料金
- 9
- 完成度
- 7
- 検証性
- 7
自律性、機能、連携、料金、成熟度、編集部の検証を基に自動算出。デプロイごとに更新されます。 どのように算出されているか?
Sierra
Agent Rank
78/ 100
- 自律性
- 9
- 機能
- 8
- 連携
- 6
- 料金
- 9
- 完成度
- 5
- 検証性
- 10
自律性、機能、連携、料金、成熟度、編集部の検証を基に自動算出。デプロイごとに更新されます。 どのように算出されているか?
Pros & cons
PolyAI
Sierra
メリット
- +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
デメリット
- −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
PolyAI
Sierra
おすすめ
Branded agent
カスタム
Enterprise
- +Voice + chat
- +Custom persona
- +White-glove implementation
- +SOC 2 II + HIPAA option
Which one should you pick?
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Frequently asked
Should I pick PolyAI or Sierra in 2026?+
Pick PolyAI if its specific capabilities (Voice, Tool use) match what you need. Pick Sierra if its specific capabilities (Voice, Tool use) match what you need. Most working teams running both can use PolyAI for primary work and Sierra for the workflows where its specific strengths matter.
What's the price difference between PolyAI and Sierra?+
Both PolyAI 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, PolyAI or Sierra?+
Both PolyAI and Sierra are Autonomous agents — neither has a meaningful autonomy advantage over the other. The decision should hinge on capabilities and pricing instead.
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Adjacent agents in the same category with overlapping capabilities — worth a side-by-side glance before you commit.
- Demo · hover to play
India's sovereign multilingual voice agent — Hindi, Tamil, Bengali, Kannada and more.
音声ツール利用メモリRAGAIカスタマーサービスエージェント — チャット・メール・音声を横断してチケットを解決し、測定可能な自動解決率を実現します。
RAGツール利用メモリ音声Demo · hover to play
See more alternatives: alternatives to PolyAI · alternatives to Sierra
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