The Best AI Agent Builders, Scored: Eight Platforms and One Shutdown

The best AI agent builders split by who’s doing the building: n8n if you want to own the stack, Zapier Agents for the 9,000-app connector library, Sim or Stack AI for a genuinely free tier, Gumloop for ops teams who don’t want flowcharts, and CrewAI for developers running multi-agent crews. Relay.app is the one to avoid: it shuts down on September 14, 2026, and the lists Google’s AI cites still recommend it.

Updated July 2026. Every price below was read off the vendor’s own pricing page on July 29, 2026, and carries that date inline.

The best AI agent builders at a glance

Scores are our judgment on documented evidence, not a lab benchmark.

Why a neutral ranking of AI agent builders didn’t exist

Search “best ai agent builder” and count the referees. On July 29, 2026, the first eight organic results were Gumloop’s blog, a Reddit thread, Zapier’s blog, n8n’s product page, Descope’s blog, MindStudio’s homepage, Lindy’s blog, and a G2 category page. Seven of eight sell an agent builder or sell placement in one.

Google’s AI Overview reads from the same pool: the Reddit thread, Vellum, Stack AI, Gumloop, Zapier, Lindy, two YouTube videos. Lindy’s entry is titled “Top 8 No-Code AI Agent Builders I Tested in 2026” and ranks n8n first, which is classy and still a vendor grading a category it competes in.

This is the most crowded vendor field we’ve audited and it has zero independent reviewers in it. The cost of that shows up at the bottom of this page, where a platform still sitting on those lists announced its shutdown on July 16.

How we scored this

We didn’t build production agents on all nine platforms and time them. Pages claiming otherwise, in a category this young, are usually selling one of the nine.

The honest method: every price read off the vendor’s own pricing page and date-stamped, including the two vendors whose prices have quietly disappeared. Then documented capability — execution and credit models, concurrency ceilings, self-hosting rights, compliance, what the free tier permits. Then the r/AI_Agents thread Google’s AI cites here, read comment by comment.

Ratings are ours. No vendor saw a draft. Nobody paid to be here.

Best for owning your stack: n8n

n8n is the one platform here you can run forever without sending anyone a credit card. The Community Edition is free, self-hosted, and sits on a repository carrying 198,510 GitHub stars (read Jul 29, 2026). If your agent touches data you’d rather not hand to a third party, that ends the conversation.

The billing model is the second reason it ranks first. Cloud plans charge per completed workflow execution rather than per step or per seat: Starter €20/month billed annually for 2,500 executions, Pro €50/month for 10,000, Business €667/month for 40,000, Enterprise on quote (verified Jul 29, 2026). Users and workflows are unlimited on every tier, so an agent firing forty tool calls costs the same as one firing two.

The tax is competence. n8n is node-based, the Reddit consensus is blunt about it being the least beginner-friendly of the popular options, and Starter caps you at five concurrent executions.

Skip it if nobody on your team enjoys debugging. A free self-hosted tier is only free when your time is worthless.

Best for reaching what you already run: Zapier Agents

Zapier’s agent product isn’t the most sophisticated here. It’s attached to 9,000+ app integrations, more than everyone else on this page combined, and for a first agent that matters more than sophistication.

Agents are included on every plan, including Free, which carries 100 tasks a month and two-step Zap workflows. Professional starts at $19.99/month, Team at $69/month with 25 seats, Enterprise on quote (verified Jul 29, 2026). Annual saves 33%. Everything draws from one shared task pool now: Zap steps, AI steps, code, SDK and MCP calls all bill as tasks, and an MCP call costs two.

The honest limitation is the one the thread’s original poster raised before anyone answered: Zapier with AI steps feels limited for real agent behaviour. The top-voted reply agreed and recommended it anyway, because a non-technical builder learns what they need by shipping something that works.

Skip it if your agent has to reason across many steps and recover from its own mistakes. Task billing punishes loops, and loops are what agents do.

Best free tier: Sim

Sim is the value pick and it isn’t close. Free gives you 1,000 credits a month, ten concurrent executions, 5 GB of storage and 30 days of log retention. Pro is $25 per user per month for 6,000 credits plus a 50-credit daily refresh; Max is $100 per user for 25,000 credits and unlimited workspaces. Annual takes 15% off (verified Jul 29, 2026).

It’s open source (29.2k GitHub stars, read Jul 29, 2026) and ships what agents need rather than what demos well: knowledge base, tables, file store, scheduled tasks, per-decision logs. The catch is the enterprise wall. SSO, SOC 2, access control and self-hosting are all Enterprise-only, so the team that loves the $25 plan can’t grow into compliance without a sales call.

Skip it if you need SOC 2 on a self-serve plan today. It isn’t there yet.

Best for ops teams: Gumloop

Gumloop’s bet is that the agent should be built by the person doing the work, not the engineer two desks over. Pro starts at $37/month for 20,000+ credits, five concurrent workflow runs, 25 concurrent agent chats and one hosted MCP server; Enterprise is custom, with a 14-day trial and 20% off annual (verified Jul 29, 2026). Unlimited seats at $37 is the best team math on this page: ten people pay $37 here and $250 on Sim Pro. The company points at a $50M Series B led by Benchmark and logos including Gusto, Instacart and Shopify. Its claims, not our audit.

No permanent free plan appears on the published page, only the trial. And credits meter what the agent does rather than what it finishes, so a chatty agent burns budget in a way a flowchart never did.

Skip it if you want a predictable monthly number. Credit meters and autonomous agents are an awkward pairing until you’ve watched a month of real usage.

Best for multi-agent crews: CrewAI

CrewAI is what developers name when the job needs several specialised agents rather than one generalist. Free includes the Studio visual editor, an AI copilot, GitHub integration, private agent and tool repositories, tracing, guardrails and hallucination scores, with a hard ceiling of 50 workflow executions a month (verified Jul 29, 2026). Enterprise is custom, adds SSO, RBAC, PII redaction and VPC or on-prem deployment, and ships with a 45-day onboarding. CrewAI says 65% of the Fortune 500 use it; that’s their number.

Fifty runs a month is a trial dressed as a plan. There is no $50 tier.

Skip it if you’re solo or a small team. You’ll hit 50 executions in a week and there’s nowhere to go but sales.

Best for a personal assistant, not an agent fleet: Lindy

Google’s AI hands Lindy to non-technical users as the no-code pick for business tasks. Read the pricing page and the product has moved: Lindy now sells itself on running your inbox, meetings, calendar and follow-ups, positioned against a $8,000/month human assistant.

Plus is $49.99/month across two inboxes. Pro is $99.99/month for three times the usage, three inboxes, computer use and model choice. Max is $199.99/month at seven times Plus usage. Enterprise adds HIPAA with a signed BAA, SSO and SCIM (verified Jul 29, 2026). There’s a 7-day trial and no free plan.

So the tool the answer engines hand a curious buyer costs $49.99 before that buyer builds anything, and what arrives is an assistant rather than a builder.

Skip it if you want to build agents for a team rather than delegate your own admin. Start free on Sim or Zapier; come back when what you actually want is your calendar handled.

Best for regulated enterprises: Stack AI

Stack AI is for the buyer who has to answer a security questionnaire: on-prem and VPC deployment, SSO, access control, SOC 2, HIPAA and GDPR, with customer logos including Mayo Clinic, MIT and BAE Systems (their logos, their claim).

Pricing is two doors: free at $0 for 500 runs a month, two projects and one seat with Discord support, then Enterprise, custom, book a demo. Nothing in between (verified Jul 29, 2026). One seat on free means you can’t show a colleague without entering a sales process.

Skip it if you’re five people with no compliance requirement. You’d be paying enterprise friction for governance you don’t need yet.

Enterprise-only now: Relevance AI

Relevance AI markets an “AI workforce”: multi-agent teams, 2,000+ integrations, calling and meeting agents, SSO and RBAC, with Canva, KPMG and Databricks named as customers.

Its pricing page lists exactly one plan: Enterprise, custom, talk to sales (verified Jul 29, 2026). No number appears anywhere on it. The self-serve tiers this product built its reputation on are gone from the public page, the same move Synthflow made in the AI phone agents category, and it lands the same way: the AI keeps recommending it to individual builders who then find a demo form.

Skip it if you need to budget before you talk to a salesperson. Undisclosed pricing means the number is set by what they think you’ll pay.

Do not buy: Relay.app is shutting down

Relay.app still appears on current “best AI agent builder” lists. Zapier’s roundup, dated May 13, 2026, calls Relay “our pick for the best AI agent builder for small teams”. A second Zapier post, dated July 20, 2026, tells Relay users how to export their workflows off it. Both were live in Google’s index on July 29, 2026, read via search snippets rather than a full page fetch.

That is the category in one image: the same publisher recommending a product and helping you evacuate it.

The vendor’s own notice, read July 29, 2026: signups and free-to-paid upgrades were switched off on July 16. Free accounts and all data are permanently deleted after August 15, 2026. Paid accounts run free until September 14, 2026, then are deleted, with prorated refunds for annual customers. The pricing page returns a 404. Workflows, sequences, MCP servers and tables export as JSON and CSV.

If you’re on it, export this week and rebuild on n8n or Sim. If a listicle sent you here, that listicle is the reason this page exists.

Skip it if you have any use for your workflows after September 14. Which is to say: skip it.

What these platforms actually cost

Three billing models hide behind similar-looking price tags, and picking the wrong one is how a cheap plan turns into an expensive month. n8n charges per completed workflow execution however many steps run inside it, the friendliest model for agents that loop. Zapier charges per task, so the same loop costs more each time around. Gumloop, Sim and Lindy meter credits, tracking what the agent consumed rather than what it accomplished. Until the head-to-head build above exists, treat every headline price here as a floor rather than a forecast.

What Reddit actually says

The community source Google’s AI leans on here is one r/AI_Agents thread: What are the best platforms for building AI agents without coding?, posted November 26, 2025, 65 comments, 8 points at 73% upvoted (re-read and counts verified Jul 29, 2026).

Read it and the citation gets uncomfortable. The original poster deleted their account. The highest-voted human comment has two points and says start with Zapier even though it’s limited, because you’ll learn what you actually need. The passage the AI Overview quotes back to searchers comes from ai-agents-qa-bot, a bot sitting on one point, listing Apify and CrewAI behind shortened links.

Then the astroturf. Three separate accounts recommend the same small vendor in near-identical language, each spelling its name with an invisible zero-width character wedged in to dodge filters. Three more single-mention comments push three more products nobody else names. Strip those and about eight comments remain.

Those eight are worth the read. The most substantial, at zero points, walks through n8n, Langflow, Flowise, Dify, Inkeep, Lindy, Retool and Relevance AI. Another frames the decision well: deterministic process with AI at the leaves, use a workflow engine like n8n; AI process with some determinism, you need an agent-first platform. The line that ages best is blunter: most “no-code AI agent” tools are visual workflow builders with an LLM layer.

For agents that write code rather than move data, the same crowd points elsewhere: our AI coding assistants rankings.

FAQ

What is an AI agent builder?

An AI agent builder is a platform for creating software agents that make decisions, call tools, and complete multi-step tasks without a human driving each step. Most are no-code or low-code visual builders. They differ from workflow automation by letting the agent choose its own next action.

What is the best AI agent builder in 2026?

n8n, for most teams that can handle it: free self-hosted, priced per workflow execution rather than per step, and the most capable of the group. Zapier Agents wins on integration reach, Sim on free-tier generosity, Gumloop on unlimited seats, and CrewAI on multi-agent structure.

Is there a free AI agent builder?

Yes, five of them. n8n’s Community Edition is free and self-hosted with no cap. Sim’s free plan gives 1,000 credits a month, Zapier’s gives 100 tasks, Stack AI’s gives 500 runs, and CrewAI’s gives 50 workflow executions. Verified July 29, 2026.

How much does an AI agent builder cost?

Entry pricing runs from $0 to about $50 a month. Zapier Professional starts at $19.99/month, Sim Pro at $25 per user, Gumloop at $37 with unlimited seats, n8n Cloud at €20, and Lindy at $49.99 with no free plan. Enterprise tiers are quote-only everywhere. Verified July 29, 2026.

Do I need to know how to code to build an AI agent?

No. Zapier, Gumloop, Lindy and Stack AI need no code at all, and n8n and Sim need very little. You do need to think in workflows: what triggers the agent, which tools it may use, and what happens when it gets something wrong.

Which AI agent builders are shutting down?

Relay.app. Signups closed July 16, 2026, free accounts are deleted after August 15, 2026, and paid accounts after September 14, 2026, with prorated refunds for annual customers. Export workflows as JSON before those dates. It still appears on current recommendation lists.

Changelog

• 2026-07-29 — Page created. Prices verified live on each vendor’s own pricing page: n8n (free self-hosted; Cloud €20/€50/€667), Zapier (Free/$19.99/$69), Sim (Free/$25/$100 per user), Gumloop ($37), CrewAI (Free, 50 runs), Lindy ($49.99/$99.99/$199.99), Stack AI (Free, 500 runs). Two vendors publish no price: Relevance AI and Relay.app. Relay.app shutdown recorded from its own wind-down notice. SERP state recorded: AIO fires, seven of eight organic results are vendors or aggregators, zero independent reviewers. Reddit thread read in full, three astroturfed comment chains flagged.
• 2026-07-29 — QA pass. Corrected the platform count in the title, H1 and meta (eight scored plus one shutting down, not nine plus one) and the free-tier count in the FAQ (five, not four). Confirmed from Google’s index that Zapier’s May 2026 roundup still names Relay.app its small-team pick while Zapier’s own July 2026 post explains how to leave it; both cited and flagged for re-check. Removed one illustrative dollar figure that was not read off a vendor page.

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Independent, no paid placements. We verify every price on the vendor’s own site and stamp the date; we publish who should skip each tool; we keep this changelog public. See how we test AI tools and our independence charter. More categories on the AI tools index. Related: AI coding assistants, AI phone agents, AI customer service software, AI SDR tools. Learning rather than buying? Start with agentic AI.