Forrester Wave Leader 2026 — enterprise voice and chat agent platform (now NiCE Cognigy).
Demo · hover to playConversational AI agent assist for contact centers — coaches reps and automates after-call work in real time.
| Spec | Cresta | Sierra |
|---|---|---|
| Agent Rank | 80 / 100 (A) | 78 / 100 (A) |
| Autonomy | Semi-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 | 4 apps | 3 apps |
| Verified | Verified | Verified |
| Released | Mar 2025 | Feb 2025 |
Calculé automatiquement à partir de l'autonomie, des capacités, des intégrations, de la tarification, de la maturité et de la vérification éditoriale. Mis à jour à chaque déploiement. Comment est-ce calculé ?
Calculé automatiquement à partir de l'autonomie, des capacités, des intégrations, de la tarification, de la maturité et de la vérification éditoriale. Mis à jour à chaque déploiement. Comment est-ce calculé ?
Pick Sierra if you want the highest autonomy and the verification loop is in place.
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Pick Cresta if its specific capabilities (Voice, Tool use) match what you need. Pick Sierra if you want the highest autonomy and the verification loop is in place. Most working teams running both can use Cresta for primary work and Sierra for the workflows where its specific strengths matter.
Both Cresta 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.
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.
Adjacent agents in the same category with overlapping capabilities — worth a side-by-side glance before you commit.
Forrester Wave Leader 2026 — enterprise voice and chat agent platform (now NiCE Cognigy).
Demo · hover to playAssistants vocaux d'entreprise pour centres d'appels — conversations naturelles qui résolvent les demandes clients.
Agent IA de service client — résout les tickets via chat, e-mail et voix avec des taux de ticket deflection mesurables.