The first decision with an AI SDR is who sends the emails: a vendor's managed agent working on your behalf, or your own team running AI outreach software. Settle that before you compare features. Then treat agents built for inbound website leads as a separate buy, and plan how you'll protect your sending domain's reputation before anything goes out.
Who should send your outreach, the vendor's agent or your own team? If you want it off your plate, look at managed agents; if you want control over every message, pick software you operate, and treat inbound agents as a different purchase altogether. The nine options here are in no particular order, with the split laid out in the table below.
Who sends what, at a glance
| Tool | Who does the work | Good for |
|---|---|---|
| 11x | Managed agent | Hands-off outbound, inbound qualification and expansion |
| AiSDR | Managed agent | Researched messages to buyers showing in-market signals |
| Apollo | Software you operate | Contact data and sequences in one system |
| Artisan | Managed agent | An AI BDR inside an all-in-one outbound platform |
| Conversica | Conversation agent | Following up leads automatically with agent conversations |
| Qualified | Inbound agent | Converting inbound website visitors into conversations |
| Regie.ai | Software you operate | Reps who email and call from one prospecting tool |
| Reply.io | Software you operate | Running your own multichannel sequences and cold email |
| Salesforge | Software you operate | High volume email and LinkedIn plus an optional agent |
Managed agents or software you run
Managed agents take the work away from your team. 11x describes its agents as fully managed, CRM-native and live in days, covering outbound prospecting, inbound qualification and expansion. Others in this group find in-market buyers from signals and write the messages, or offer an AI BDR as part of an all-in-one outbound platform.
How a vendor bills shapes how you should trial it. AiSDR's own page bills by people prospected rather than by seat, so count the prospects you'd want reached each month, not the number of reps you've got.
Software you operate is the other route. Reply.io, Salesforge, Regie.ai and Apollo give your team the machinery (sequences, mailboxes, data, dialling) and your people decide who hears what. Several now include an agent of their own as well, so the line between the two routes is blurring. Ask who's accountable when a message goes wrong.
Operated tools work for a team that already knows its ideal customer and has someone to own the messaging. Managed agents help founders who haven't got that person, but you're trusting a vendor with your brand's voice in strangers' inboxes. If you're weighing broader platforms, my list of all-in-one outbound platforms and my guide to sales engagement platforms cover the operated side in more depth.
Agents that work your inbound leads
Inbound agents wait for buyers to come to you. Qualified's Piper works on inbound website leads and turns visitors into conversations, while Conversica's agents start conversations with leads rather than sitting and waiting for a reply.
These only make sense with steady inbound traffic. If your website brings in a handful of enquiries a month, a fast human reply will do more for you. If your team spends its time on calls rather than email, the AI outbound calling tools are a closer match, and AI sales assistants for call notes and coaching help once a conversation's under way.
Each platform, A to Z
Alphabetical, one line each on who it's built for.
11x
Best for: Teams wanting AI agents for outbound prospecting, inbound qualification and expansion that the vendor says are fully managed and CRM-native.
AiSDR
Best for: Small teams who want in-market buyers found from real-time signals and deeply researched outreach written for them.
Apollo
Best for: Go-to-market teams wanting contact data, intelligence and execution joined up, with connections to Claude and ChatGPT on the vendor page.
Artisan
Best for: Founders wanting one outbound platform powered by AI employees, with an AI BDR built in.
Conversica
Best for: Companies wanting lead conversations started and followed up by AI agents rather than waiting for a reply.
Qualified
Best for: B2B teams with steady inbound traffic who want Piper, an AI SDR agent, working their website leads.
Regie.ai
Best for: Reps who both email and call, with buyers found from your website, enriched contacts, why-now research and dialling up to five lines at once.
Want AI doing the heavy lifting in your marketing?
I build the systems that handle the boring 80 percent, so you get your week back. Done properly, with the human kept in.
Reply.io
Best for: Teams running sequences themselves, with multichannel outreach, cold email, a B2B database and analytics in one platform.
Salesforge
Best for: Small teams after unlimited mailboxes and LinkedIn senders, with warm-up and an AI SDR called Agent Frank in the same product.
Protecting your sending domain
Whoever sends, it's your domain's reputation on the line. High-volume outreach from your main domain can push your ordinary email into spam folders as well, and that's a slow thing to repair. Plenty of teams send cold outreach from a separate domain for exactly this reason.
Several of the operated tools talk about unlimited mailboxes and warm-up. That's useful, but it isn't a plan on its own. Ask which domain the emails will come from, who sets up the authentication records, how warm-up works and what the daily sending limit per mailbox will be. If a managed vendor sends for you, ask the same questions and get the answers in writing.
Bad data hurts reputation too, because bounces count against you. If your contact list is the weak point, compare data enrichment tools or email finders before you send a thing.
My advice on who should send
If you're a founder with no sales hire and a clear offer, a managed agent can get conversations started while you run the business, as long as you read what it sends in the first fortnight. If you've got even one person who owns outbound, give them software they operate; they'll learn faster and keep your voice consistent. Add an inbound agent only when your website brings in more leads than your team can answer quickly.
Whichever route you pick, start small: one segment, one domain, a few weeks. It's far easier to scale a campaign that's working than to rescue a domain that's been burned.
Five questions for any vendor
- Who writes and approves the messages, and can I see every one before it goes out?
- Which domain and mailboxes will send, and who owns them if we part ways?
- How do you handle warm-up, daily sending limits and bounces?
- How do you bill: per seat, per prospect or per outcome?
- Where does the contact data come from, and how do you handle opt-outs and removal requests?
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Frequently asked questions
What is an AI SDR?
An AI SDR is software that does some or all of a sales development rep's work: finding prospects, researching them, writing outreach and following up. Some run outreach for you; others give your team the tools to run it.
Will an AI SDR replace my sales team?
It can take on prospecting and first-touch outreach, but someone still needs to own the offer, check messages and take the conversations that turn into deals.
Is an inbound AI agent the same as an outbound AI SDR?
No. Inbound agents respond to people already on your website or in your pipeline. Outbound AI SDRs contact people who haven't heard of you yet, which brings the domain reputation questions on this page.
Should I send AI outreach from my main domain?
It's safer not to. Many teams use a separate sending domain so that a deliverability problem doesn't affect everyday email from the main one.
Are AI-written cold emails legal?
Rules on cold email and consent vary by country and by whether you're contacting businesses or individuals. Check your regulator's guidance before you start, whichever tool you use.
