AI agent builder reviews

10 tools, one page each: the verdict first, then plans, limits, the billing unit and the catch.

Prices checked Nov 15, 2026How we score

One run costs one execution, whether the workflow has 3 steps or 300.

The cheapest hosted way to wire 3,500 apps together, with agents on every plan.

If an app exists, Zapier probably connects it: 9,000+ of them.

Less a builder than a teammate you brief in Slack or by text.

One plan, unlimited seats, and a meter that follows model list prices.

A support agent with a helpdesk attached, priced per conversation.

The obvious pick inside a Microsoft tenant, and a detour outside one.

Multi-agent "workforces" with evaluations, sold through a sales call.

Chat and voice agents with real release tooling, behind a demo.

The team wound Flowise down in 2026. The code stays, the support does not.

Compared, without a full review yet

Activepieces, Langflow, StackAI, Dify are scored with the same formula and sit in the rankings. Their rows link to the comparison tool.

Tools compared without a full review
Tool	Score	Entry price	Billed in	Free plan or trial	Integrations	Self-hosting	Official page
ActivepiecesFrom $20/mo · checked Nov 15, 2026	9.4/10	From $20/mo	Credits (one per run)	Free plan	770+	Yes, limited	Check price at Activepieces
LangflowFree, open source · checked Nov 15, 2026	9.0/10	Free, open source	No platform fee	Free self-hosted edition	Not stated	Yes	Get Langflow free
StackAIPrice on request · checked Nov 15, 2026	8.8/10	Price on request	Runs	Free plan	500+	Enterprise only	See plans at StackAI
DifyFrom $59/mo · checked Nov 15, 2026	8.7/10	From $59/mo	Message credits	Free plan	Not stated	Yes	Check price at Dify