Short answer: Parloa, Sierra, and Decagon are enterprise customer-service agent vendors with different approaches to voice, implementation, and agent authoring. Devotel Orbit is the integrated platform option: its agent workspace sits alongside voice and communications surfaces in the same product. The right choice depends on whether your team wants a specialist agent program connected to existing infrastructure or wants agents and the platform around them evaluated together.
This comparison separates public product posture from deployment details that need a vendor confirmation. It does not infer pricing, model availability, certifications, or a specific integration from a broad product label. Treat each cell as a starting point for a technical evaluation, not a contract or a guarantee for every plan.
Side by side: four different operating models
| Capability | Parloa | Sierra | Decagon | Devotel Orbit |
|---|---|---|---|---|
| BYO LLM posture | Partial — model orchestration is part of the platform; confirm the available models and control boundaries for your deployment | Partial — confirm supported models and customer control during evaluation; unrestricted model choice is not the headline posture | Partial — confirm model choices and tenant controls for the plan under review | Partial — evaluate the currently supported provider configuration for your tenant; this is not a claim of an open model marketplace |
| Telephony ownership | No — integrates with a customer's contact-center and telephony estate | No — customer-service agent platform, not a wholesale carrier | No — support-agent platform, not a wholesale carrier | Yes — voice and agents are available within the Devotel Orbit platform; verify the specific coverage and routing design for your use case |
| SIP / BYOC | Yes — voice deployments integrate with enterprise telephony; validate the target SIP and carrier design | Partial — validate the carrier, SIP, and contact-center path for the proposed deployment | Partial — voice availability and telephony fit depend on the deployment; confirm SIP/BYOC requirements directly | Yes — SIP trunking and voice connectivity are part of the platform; confirm the required topology before rollout |
| Omnichannel breadth | Yes — voice and digital customer-service channels | Yes — customer-service agents across digital and voice interactions | Partial — broad support-agent use cases, with voice and channel fit to verify | Yes — voice agents sit alongside messaging and other communications surfaces |
| Deployment model | Enterprise cloud deployment; confirm architecture and residency requirements in procurement | Enterprise SaaS with hands-on implementation and service design | SaaS platform configured by the customer, with rollout support as needed | Cloud platform account; confirm tenant-specific configuration and controls for the deployment |
| Agent authoring | Enterprise agent platform with reusable configurations; expect deployment work | Agents shaped around the enterprise service operation, with expert implementation | No-code builder for support teams to configure agents | The dashboard's Agents workspace, alongside the Voice workspace |
These are categorical comparisons, not a substitute for a solution design. “Yes” describes the public product posture, not a promise that every integration, region, or feature is included in every plan. “Partial” means the capability needs a specific scope or deployment check. Model options, voice routing, data handling, and channel availability can change; confirm the answers in the vendor's current documentation and proposed design. No pricing or certification claims are made here. Parloa, Sierra, and Decagon teams are invited to send corrections to any cell; we will update the row and identify the corrected item here rather than leave an outdated comparison in place.
Three specialist archetypes
Parloa: voice-AI-native enterprise automation
Parloa's product is organized around enterprise AI agents for customer service, including voice. That voice-AI-native posture is relevant when a program starts with high-volume calls, natural-language self-service, and the need to connect automation to an existing contact center. Its enterprise integration and deployment work is part of the buying motion: a reusable agent configuration does not eliminate the work of mapping company policy, systems, and escalation paths. Buyers should confirm which models, voice routes, and operational controls apply to the proposed deployment rather than infer them from the platform's broad orchestration story.
Sierra: expert-serviced customer-service agents
Sierra pairs a customer-service agent platform with hands-on design and implementation for enterprise operations. That approach fits teams that want agents shaped around their service policies, brand, and business systems and are prepared to involve a vendor team in the rollout. In a shortlist, compare not only the launch support but also the operating model afterward: who can adjust prompts, tools, and workflows, how those changes are reviewed, and which model and channel choices remain under the customer's control. Sierra is not simply a self-serve voice builder; its implementation motion is part of its proposition.
Decagon: a no-code support-agent builder
Decagon brings agent configuration closer to support teams through a no-code builder. That can suit organizations that want service operators to refine support agents without treating each iteration as a large software project. The fit still depends on the actual workflow: what systems an agent can read or update, how it hands work to a person, which channels are included, and how voice connects to the existing contact center. Teams with voice at the center should validate routing and SIP/BYOC requirements directly instead of treating “AI agent” as proof of a particular telephony design.
Where Devotel Orbit fits
The first decision is not which logo wins a feature checklist. It is whether the requirement is a specialist agent platform integrated with existing communications infrastructure, or an integrated platform where agents and communications are evaluated together. Parloa, Sierra, and Decagon each make a different specialist case: voice-AI-native enterprise automation, expert-serviced customer-service agents, and a no-code support-agent builder. A team buying one of those models should assess the specialist's implementation, controls, and integrations on their own merits.
Devotel Orbit offers a different buying frame. The dashboard places agent configuration in the Agents workspace and voice operations in the Voice workspace, within the broader communications platform. That gives a team a place to evaluate agent and voice surfaces together, rather than assume a specialist agent product also owns the underlying carrier or every adjacent channel. For a consolidated evaluation, test the agent workflow, the voice route, channel needs, tenant controls, and operational handoff against one real use case.
This is not a claim that Orbit has every specialist feature, unrestricted model choice, or the same implementation model as these vendors. Nor does an integrated product description prove a requirement is shipped in a particular plan or region. Use a hands-on evaluation to confirm what is available to your tenant; where the product or a vendor's documentation does not substantiate a claim, the answer is not “yes.” A specialist can be the better fit when its particular service model or agent-authoring approach is the requirement. Orbit is worth including when the agent and the communications platform should be considered as one operating surface.
A practical evaluation sequence
Start with one representative customer interaction rather than a feature checklist. For a voice use case, define the call's entry point, the agent's task, the systems it may access, the conditions that require human handoff, and the recovery path if a dependency fails. For a digital support interaction, use the same method and include the channel and escalation path. Give each vendor the same scenario so that “omnichannel” or “enterprise-ready” does not stand in for a testable design.
Then ask each team to walk through six decisions:
- Model control: Which models are supported for this deployment, who selects them, and what can the tenant change?
- Telephony: Who owns the carrier relationship, and how does the agent connect to the existing contact center or SIP design?
- Channels: Which channels are included in the proposed architecture, and where does context persist when a customer switches channels?
- Authoring: Who can change the agent after launch, and what review or implementation work does each change require?
- Operations: What can the tenant observe, control, and troubleshoot without a vendor engagement?
- Boundaries: Which features, integrations, and deployment options are confirmed for the actual plan and region?
For Orbit, assess the shipped agent workflow in the dashboard and its connection to the voice surface; do not treat a broader platform description as evidence for a capability your tenant has not verified. For each specialist, check the proposed integration and service model rather than assuming that “agent platform” means the same thing across vendors. Record unanswered items as open requirements, not favorable cells.
How to read the comparison
The three specialists are not interchangeable. Parloa is the clearest voice-AI-native enterprise archetype. Sierra is the expert-serviced customer-service approach. Decagon is the no-code support-agent builder. Those descriptions identify where to focus a proof of fit; they do not rank product quality or guarantee a specific capability in your configuration.
The integrated-versus-specialist distinction is also not a verdict. A buyer with a strong existing contact-center estate and a preference for a specialist deployment may reasonably choose one of these vendors. A buyer who wants to evaluate the agent beside the voice and communications platform should include Devotel Orbit in the same proof of fit. The useful outcome is a decision based on the workflow, customer-owned controls, and verified implementation boundaries—not a claim that every team should buy the same shape.
Related reading
For the broader platform decision, read AI-agent-first vs UCaaS incumbent. For the lower-level speech and orchestration choices, see AI voice infrastructure: STT, TTS, and orchestration. For a vendor-on-vendor view of the three specialists, continue to Parloa vs Sierra vs Decagon.
Published 15 October 2026.