# The Best AI Support Agents (2026)

> Source: https://theagentsindex.com/best-ai-support-agents (curated, quality-gated, re-verified)

Every AI support agent in this category sells outcome- or resolution-based pricing, but they split sharply on one thing that matters more than any feature list: can you actually try it, and at what price? Two of the nine are genuinely self-serve with a fully posted price and a free trial: Intercom Fin ($0.99 per resolution, 14-day no-card trial) and Auto-Respond, the one small-business entry here, priced per channel from $10/month for a voice number plus $1 per minute of talk time, with a 7-day trial. Zendesk AI Agents sits in its own middle case: a 14-day no-card trial and a fully public per-seat price ($55–$115/agent/month for the Suite plans that include AI Agents) make signup genuinely self-serve, but the usage meter on top of that seat price, the per-resolution rate, is undisclosed, so you can start without a sales call yet still can't fully price it out in advance. Botsify is the only other listing here with any public price at all, $149/month for its Done-for-You plan, but that price buys a managed build Botsify's own team assembles for you, not a self-serve dashboard. Sierra, Decagon, Crescendo, Cresta and Ada publish no full-suite pricing whatsoever. You start with a pilot or a contract, not a signup form or a posted rate.

A second, more subtle split cuts across the six full-resolution names. Sierra, Decagon, Crescendo, Ada and Zendesk AI Agents are all built to resolve a conversation end to end and hand off to a human only on exception. Cresta is built the other way around: its AI Agent resolves conversations too, but the platform's bigger emphasis is Agent Assist and the newer Knowledge Agent, which keep supporting the human rep continuously rather than stepping back once a human takes over. It's the one listing here explicitly built to augment a blended AI-and-human operation, not just replace one. Botsify, on its Done-for-You plan, is also built for full resolution rather than augmentation, closer in intent to Sierra, Decagon, Crescendo, Ada and Zendesk than to Cresta, but publishes no resolution rate or named case study to weigh against them.

A third split cuts across developer access, independent of price. Ada and Zendesk AI Agents are the only two of the enterprise-leaning names that ship a fully documented, publicly-browsable developer API (Ada's Conversations/Email API plus an MCP server; Zendesk's long-standing developer.zendesk.com platform and app marketplace), a real developer surface Sierra, Decagon and Crescendo don't publish at all. Botsify also ships a genuine API (a public Postman collection), despite its own price being public but its onboarding still a managed build rather than self-serve. That makes Ada, Zendesk AI Agents, Botsify and Auto-Respond (a REST webhook plus a Lead Reply API) the four listings here a developer can actually integrate against without a sales-gated SDK.

So this is not a single top pick. It is all nine independently researched AI support agents in our index, grouped by those real buying decisions: self-serve versus publicly-priced-but-managed versus enterprise sales-led, full replacement versus blended augmentation, and which ones actually ship a usable developer API. Each carries an honest note on what it actually gets you and where its pricing or proof falls short of the pitch.

| # | Name | What it is | Pricing | API |
| --- | --- | --- | --- | --- |
| 1 | [Fin](https://theagentsindex.com/intercom-fin.md) | Intercom's customer agent that resolves support conversations across chat, email, voice and social channels. | From $0.99/outcome | Yes |
| 2 | [Auto-Respond](https://theagentsindex.com/auto-respond.md) | AI answering service and voice agent that answers calls and marketplace texts, qualifies leads and books jobs. | From $10/month | Yes |
| 3 | [Zendesk AI agents](https://theagentsindex.com/zendesk-ai-agents.md) | Customer-service AI agents for messaging, email and voice, billed per automated resolution. | From €25/seat/month | Yes |
| 4 | [Botsify](https://theagentsindex.com/botsify.md) | White-label platform for building prompt-based AI chat and voice agents that agencies resell under their own brand. | From $149/month | Yes |
| 5 | [Sierra](https://theagentsindex.com/sierra.md) | Enterprise platform for customer-service AI agents across voice, chat, email and messaging, priced by outcome. | On quote | Yes |
| 6 | [Decagon](https://theagentsindex.com/decagon.md) | Enterprise platform for building and running AI customer-support agents across chat, voice and email. | On quote | Yes |
| 7 | [Crescendo](https://theagentsindex.com/crescendo.md) | AI-native CX platform: agents resolving support across voice, chat, email and SMS, with a staffed team behind them. | From $1.25/resolution | Yes |
| 8 | [Ada](https://theagentsindex.com/ada.md) | Enterprise customer-service AI agent platform spanning voice, messaging and email with tool-based actions. | On quote | Yes |
| 9 | [Cresta](https://theagentsindex.com/cresta.md) | Enterprise contact-centre platform with autonomous voice and digital AI agents plus real-time human agent assist. | On quote | Yes |
| 10 | [IrisAgent](https://theagentsindex.com/irisagent.md) | AI support agents that resolve chat, email, voice and text inside your existing helpdesk. | Free, then $500/month | Yes |
| 11 | [Maven AGI](https://theagentsindex.com/maven-agi.md) | Enterprise AI agent platform that resolves customer conversations across chat, email, voice and internal tools. | On quote | Yes |
| 12 | [Aide](https://theagentsindex.com/aide.md) | Governed AI agent that resolves customer conversations end to end inside Zendesk, Front, Gorgias or Gmail. | From $99/month | Yes |
| 13 | [AiZipZap](https://theagentsindex.com/aizipzap.md) | Free browser agent that turns a pasted customer request into a source-quoted handoff and an editable reply draft. | Free | No |
| 14 | [Mixdesk](https://theagentsindex.com/mixdesk.md) | Omnichannel customer engagement platform with AI Agents for support, sales and lead qualification. | Free, then $49/month | Yes |

## Methodology

Every entry is a Published listing that already cleared this site's per-listing quality gate on sourced facts, admitted weaknesses, a "best for" and a "not for," re-verified on a rolling cadence (see /methodology). support-agents was the smallest category on the site to clear the 4-listing minimum for its own ranking and has since grown to 9. Every support-agent listing on the site still appears here, unlike the flagship /best-ai-agents page's narrower "Support agents" group. Ordering leads with the two fully self-serve options (Intercom Fin, then Auto-Respond), then Zendesk AI Agents' self-serve-signup-but-undisclosed-usage-rate case, then Botsify's publicly-priced-but-managed tier, then the enterprise, sales-led options, roughly by how much independent, named proof each publishes (case studies, ARR, funding) rather than by vendor claims alone; the live score chip on every card (evidence, honesty, depth, freshness) is computed the same way as that tool's own listing page.