Aryan Agarwal
Stack AI feels like an app builder. Gravity feels like a hiring interface for a process. Both are tools for non-developers to put AI to work, but the design centres are different.
What Stack AI is, and where it actually shines
Stack AI is a no-code platform from a team out of New York. The product gives you a canvas where you can build LLM-powered applications and agents with inputs, prompts, models, retrievers, and outputs. The end result is often a usable internal app with a UI on top.
Where Stack AI shines:
- Internal LLM apps with custom inputs and outputs.
- Document Q-and-A products where retrieval is the work.
- Enterprise teams that want a contained no-code surface for AI experiments.
- Use cases where the agent has a UI rather than running headlessly.
- Teams that prefer a builder paradigm for collaboration.
The product is mature, the canvas is polished, and the enterprise posture has grown over time.
What Gravity does differently
Gravity does not produce an app. It produces a running agent. The interface to make one is a sentence:
"Every Tuesday at 3pm IST, scan our LinkedIn DMs for inbound inquiries about partnerships. Draft a polite reply with our partnership one-pager link, post each draft in our #bizdev Slack channel for me to approve. Stop after 15 inquiries."
No UI is built. There is no app to launch. The agent runs on schedule, posts to Slack, waits for approval. Headless. Describing outcomes is the entire surface.
Side-by-side capability comparison
| Capability | Stack AI | Gravity |
|---|---|---|
| Output of the platform | An app with a UI | A running headless agent |
| Setup model | Drag-drop canvas | One sentence |
| Operator persona | Builder, sometimes engineer | Operator, sometimes founder |
| RAG support | Strong | Available, not the focus |
| Schedule and triggers | External or trigger nodes | First-class in the prompt |
| Approvals and stop conditions | Build manually | Native runtime feature |
| Hosting | Hosted, with enterprise options | Fully hosted |
| Pricing model | Tiered, enterprise contracts | Bundled monthly fee |
The builder-vs-runtime split
Stack AI is a builder. Gravity is a runtime. The distinction matters because builders give you a thing to use, runtimes give you a thing to forget about.
If you want an AI form that processes inputs and shows outputs, a builder is right. You will use the app daily, and the canvas reflects how the app behaves.
If you want a process that runs while you do something else, a runtime is right. There is nothing to use. The agent runs, you see the results in Slack or Notion or wherever the outcome routed.
The two often coexist. We have seen teams build an internal app in Stack AI for analyst-facing workflows, while running Gravity agents for the recurring operations the analysts do not want to babysit. See also why most AI agents stop after one task.
Pricing reality
- Stack AI: Tiered pricing with enterprise contracts at the top. Per-credit or per-seat models exist.
- Gravity: Bundled monthly fee.
When Stack AI is the right choice
- You are building an LLM app with a UI for end users.
- RAG is the core of the work.
- You want a canvas with strong template libraries.
- Enterprise procurement values a packaged platform.
- Your team enjoys building visually.
When Gravity is the right choice
- You want a headless agent.
- You want operational outcomes, not an app to babysit.
- You change agents by editing a sentence.
- You want one bundled bill.
- You want native scheduling and approvals.
Migration: what changes if you switch
- Pick a Stack AI app to migrate.
- If it is a UI app, decide if you actually need the UI. If yes, stay on Stack AI. If no, write the outcome sentence.
- Reconnect OAuths in Gravity.
- Run a dry run.
- Cut over.
Frequently asked questions
What does Stack AI do?
Stack AI is a no-code platform for building LLM-powered applications and agents. The flagship surface is a visual builder where you connect inputs, prompts, models, retrievers, and outputs into a runnable app.
Is Stack AI used for enterprise or startups?
Both. The product has tiers covering individual builders through enterprise contracts. The enterprise focus has grown over time.
How is Gravity different from Stack AI?
Stack AI gives you a canvas to assemble an app. Gravity gives you a sentence and composes the agent. The deeper difference is that Stack AI feels like a product builder, Gravity feels like a hiring interface for a process.
Can Stack AI agents take action?
Yes, with tool nodes and API calls. The build pattern is more app-like than ops-like. Scheduled, long-running, action-taking agents are doable but not the design centre.
Which is better for shipping fast?
Gravity. Time to first running agent is a sentence and a save. Stack AI requires building a graph, even if the graph is simple.
Three takeaways before you close this tab
- Builders make apps. Runtimes run processes. Pick by what you want at the end.
- UI is sometimes the wrong primitive. If nobody is going to use the app, you do not need an app.
- Stack AI and Gravity coexist nicely. Many teams run both.
Sources
- Stack AI. "Official product page." stack-ai.com
- Stack AI. "Pricing page." stack-ai.com/pricing
- Stack AI. "Documentation." docs.stack-ai.com