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Shortlist by channel

What is the best AI customer service agent for phone calls?

No independent source establishes any agent in this catalogue as answering customers over phone calls. Ada, Agentforce and Breeze Customer Agent document it in their own material, which is where a shortlist starts rather than where it ends. 18 of the 22 agents reviewed have any published evidence for phone calls; for the rest it is unknown, which means nobody has published it, not that the product cannot do it. Nothing here has been tested by this portal, so treat every name below as a shortlist to validate, not a winner.

All shortlists · Markdown record · How this is grouped

An outside source reports it serving this segment

External report0 of 22

A customer, analyst or journalist with no stake in the sale describes the product working here. This is the strongest evidence the portal holds, and it is still somebody else's deployment, not yours.

No agent in the catalogue is in this group.

The vendor documents this segment, and nobody else has written about it

Vendor-documented18 of 22

The vendor says it serves this segment. That is a reasonable place to start a shortlist and it is not confirmation, because no independent source has reported on it either way.

Listed alphabetically. Position inside a group carries no meaning: these agents are not ranked against each other.

The vendor documents this segment, and nobody else has written about it, for phone calls
AgentWhat puts it hereCustomer workflows with evidence
AdaAda0 externally reported, 7 vendor-documented, of 7
AgentforceSalesforce0 externally reported, 7 vendor-documented, of 7
Breeze Customer AgentHubSpot0 externally reported, 2 vendor-documented, of 7
CrescendoCrescendo2 externally reported, 1 vendor-documented, of 7
DecagonDecagon1 externally reported, 6 vendor-documented, of 7
Five9Five92 externally reported, 0 vendor-documented, of 7
ForethoughtForethought (Zendesk)3 externally reported, 0 vendor-documented, of 7
Genesys Cloud CXGenesys0 externally reported, 2 vendor-documented, of 7
Kore.aiKore.ai1 externally reported, 1 vendor-documented, of 7
LivePersonLivePerson0 externally reported, 2 vendor-documented, of 7
NiCE CognigyNiCE1 externally reported, 1 vendor-documented, of 7
NiCE CXoneNiCE3 externally reported, 0 vendor-documented, of 7
PolyAIPolyAI2 externally reported, 1 vendor-documented, of 7
SierraSierra0 externally reported, 7 vendor-documented, of 7
SprinklrSprinklr1 externally reported, 1 vendor-documented, of 7
TalkdeskTalkdesk3 externally reported, 2 vendor-documented, of 7
Yellow.aiYellow.ai0 externally reported, 2 vendor-documented, of 7
Zendesk AI AgentsZendesk1 externally reported, 6 vendor-documented, of 7

A limitation is documented for this segment

Caveat documented0 of 22

A cited source describes a limit or a bad experience here. It sits below vendor documentation because it is not evidence of fit, and above the agents nobody has written about because somebody at least looked. Read the condition: it may not apply to you at all.

No agent in the catalogue is in this group.

Nothing published for this segment

Not established4 of 22

No reviewed source places these agents here, by the vendor's own documentation or otherwise. That is a gap in the public record, not a finding against the products, and several of them may suit you.

Listed alphabetically. Position inside a group carries no meaning: these agents are not ranked against each other.

Every claim behind these groups

Each agent above with evidence for phone calls, and the claims that placed it, with the source type and the date it was checked.

  • Ada

    Vendor-documented
    • Chat, voice, email and social messaging are documented. Voice and social connections use supported external platforms; confirm the intended channel integration.Vendor-reported
      Source
      Key concepts (Ada docs)
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID ada-channels

  • Agentforce

    Vendor-documented
    • Salesforce describes messaging, web, mobile and voice service experiences. Channel availability and setup should be checked for the specific Service Agent offering.Vendor-reported
      Source
      AI customer service agents (Salesforce)
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID agentforce-channels

  • Breeze Customer Agent

    Vendor-documented

  • Crescendo

    Vendor-documented
    • Crescendo states its Concierge agent handles "Voice, chat, email, SMS, WhatsApp" from a single AI layer, with a website chat widget, mobile apps and API access also documented.Vendor-reported
      Source
      Crescendo — Concierge Agent
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID crescendo-cmp-channels

  • Decagon

    Vendor-documented

  • Five9

    Vendor-documented
    • Five9 markets both "Voice AI Agents" for automating routine customer interactions and "Digital AI Agents" providing personalized self-service via chatbots and social messaging.Vendor-reported
      Source
      Conversational, Generative and Agentic AI
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID five9-channels

  • Forethought

    Vendor-documented
    • The vendor lists chat, email, voice, SMS, Slack, mobile apps and a headless API as supported channels.Vendor-reported
      Source
      Forethought Solve
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID forethought-channels

  • Genesys Cloud CX

    Vendor-documented

  • Kore.ai

    Vendor-documented
    • Kore.ai's channel documentation lists digital channels (Slack, LINE, Microsoft Teams, WhatsApp, Messenger, Twilio SMS, Telegram, Zendesk, Instagram, Genesys, Genesys Open Messaging, Email), voice channels (Realtime LLM Voice, Pipeline Voice, VXML IVR, Genesys Audio Connector, AudioCodes), SDK channels (Web SDK, API, Mobile SDK), webhooks, and the AG-UI and Agent-to-Agent protocols.Vendor-reported
      Source
      Channels - Kore.ai Agent Platform documentation
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID kore-ai-cmp-channels

  • LivePerson

    Vendor-documented
    • LivePerson states its AI agents can be built and launched with LLMs 'across messaging and voice', and its Conversational Cloud page names SMS, WhatsApp and voice among supported channels.Vendor-reported
      Source
      Generative AI Tools — LivePerson
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID liveperson-cmp-channels

  • NiCE Cognigy

    Vendor-documented
    • Documented endpoints cover web chat, telephony via Cognigy Voice Gateway, WhatsApp, Facebook Messenger, Microsoft Teams, Slack, LINE Messenger, Twilio and Twilio SMS, Intercom, Userlike, Zendesk Sunshine Conversations, Genesys, 8x8, NiCE CXone, RingCentral Engage, Zoom, Azure Bot Services, plus REST, Socket and Webhook endpoints.Vendor-reported
      Source
      Endpoint Reference - Overview | Cognigy Documentation
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID nice-cognigy-cmp-channels

  • NiCE CXone

    Vendor-documented
    • NiCE states its self-service AI agents deliver natural language experiences that are equally fluent over digital or voice channels, with multimodal capabilities blending voice, text, multimedia and device capabilities.Vendor-reported
      Source
      AI Agents for Self-Service
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID nice-cxone-cmp-channels

  • PolyAI

    Vendor-documented
    • PolyAI is voice-first — its documentation calls it an "enterprise platform for building voice and chat agents" and its pricing is per minute of voice-agent use — with secondary documented channels covering web chat, SMS and RCS, email, and iOS/Android SDKs (including in-app voice calling).Vendor-reported
      Source
      PolyAI Docs — documentation index (llms.txt)
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID polyai-cmp-channels

  • Sierra

    Vendor-documented
    • Vendor-listed channels include phone, website and app chat, WhatsApp, Apple Business Chat, SMS and email. Live Assist supports staff, and Sierra also documents publishing selected agent journeys to ChatGPT.Vendor-reported
      Source
      Channels (Sierra)
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID sierra-channels

  • Sprinklr

    Vendor-documented
    • Sprinklr states AI agents operate across "chat, social, voice, messaging, email, and more", moving between voice, chat, email and social while retaining conversation context.Vendor-reported
      Source
      Sprinklr AI Agents
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID sprinklr-channels

  • Talkdesk

    Vendor-documented

  • Yellow.ai

    Vendor-documented
    • An Escalate to Agent tool places chat conversations in Inbox queues with configurable priority and assignment and delivers a conversation summary to the human agent, plus a Transfer Call tool for PSTN forwarding or SIP transfer on voice.Vendor-reported
      Source
      Escalation (Yellow.ai docs)
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID yellow-ai-cmp-handoff

  • Zendesk AI Agents

    Vendor-documented
    • Zendesk advertises web, mobile, social, email, and voice. Check channel-specific documentation and availability for the selected agent.Vendor-reported
      Source
      Zendesk AI Agents product overview
      Checked
      History
      First published
      Correct this
      Request a correction with a public source. Claim ID zendesk-cmp-channels

How these groups are formed

  1. Agents are grouped by what the cited sources establish for this segment, not scored against each other.
  2. An outside source reporting the product in this segment comes first, then the vendor's own documentation, then a documented limitation, then silence.
  3. Within a group the order is alphabetical, because the evidence does not support ranking one against another.
  4. No agent is dropped: the ones with nothing published are named too.

Groups are derived from the cited claims at build time and describe the evidence, not the products. Nothing here has been tested, so a higher group means more has been established about an agent in this segment, not that it performs better. An agent can be well suited to you and sit in the last group simply because nobody has written about it. Published review-site ratings do not order these groups either: where a record carries one it is cited on the profile, but those ratings score whole products against each other — one vendor's bundled chat widget against another's full help desk — and none of them measures the AI agent on its own.

The methodology page explains why the portal groups evidence rather than scoring products.

Other shortlists

Facts last checked . No agent on this page has been tested by this portal.