This comparison covers two products that buyers often line up against each other when they shouldn't. Agent.ai is an AI agent marketplace. Gravity is an outcome runtime. The labels look similar at a glance, the buyer experience is not.

I'm Aryan, founder of Gravity. The point of this post is not to pick a winner. It's to help a buyer pick the right category for their specific job. Both products do real work for real customers. They do different work, and the cost of choosing the wrong category is a quarter of mismatched expectations, not a refund.

Why I'm writing this comparison

I shut down three startups before Gravity. The pattern that killed two of them was buying a tool whose category did not match the job. A workflow builder for what was really a chat assistant problem. A chat assistant for what was really a scheduled agent problem. The tools were good. The category was wrong.

So I write these head-to-heads like I wish someone had written them for me in 2022: not feature lists, but category framing. The question I want a buyer to answer is "which shape of work am I doing?" Once that is clear, the product choice falls out almost automatically. The comparisons between Agent.ai and Gravity below are organised around that question, not around who wins on any single benchmark.

What Agent.ai does

Agent.ai, launched by Dharmesh Shah of HubSpot, positions as a marketplace of pre-built AI agents. The user browses agents others built and either uses them as is or composes them into chains.

Where Agent.ai shines:

The marketplace model has worked for Apple, Stripe, and HubSpot itself. Dharmesh knows the playbook, and a curated catalog is genuinely useful for buyers who do not yet know what they need.

What Gravity does differently

Gravity is not a marketplace. There is no catalog, no shopping. The user writes one sentence about the outcome they want, and Gravity composes the agent from scratch. The catalog is implicit, inside the runtime.

"Every morning at 7am IST, summarise the last 24 hours of /r/sideproject for posts about AI agents, draft a one-paragraph reply for any post asking how to build one, and queue replies in my Reddit drafts."

On a marketplace, you search for an agent that does this, find one close enough, then tweak. On Gravity, the sentence is the agent. No search. Describing outcomes is the only interface in Gravity.

Side-by-side capability comparison

CapabilityAgent.aiGravity
Discovery modelBrowse catalogWrite a sentence
CustomisationTweak parameters of a pre-built agentSentence is the spec
Best fitCommon tasks with templatesSpecific tasks for your business
Time to first runMinutes if a template matchesAbout 60 seconds for any task
ComposabilityChain agents from the catalogSingle agent does the chain
PricingFree tier plus creditsBundled monthly fee
Best forMarketers exploring AIFounders shipping recurring jobs

The category split

Agent.ai bets that most users want to start with a known good template. Gravity bets that the outcome is unique enough that templates miss the point. Both bets are defensible; they pick different first-time experiences.

The choice is not always about features. It's about how your team works and what you optimise for. We made the same argument in bootstrapping an AI agent platform: pick the category whose default fits how you already think.

Pricing reality

For a deeper look at recurring agent cost, see our note on AI agent cost models and the breakdown of how bootstrapped agent economics change when bills are bundled instead of metered.

A 60-second decision framework

If you have one minute and need to choose, run through these four questions in order. The first one to give you a hard answer is the answer.

  1. Does this work need to recur on a schedule without my involvement? If yes, lean Gravity. If no, Agent.ai or another single-session tool is fine.
  2. Do I want to describe the outcome, or assemble the steps? Outcome means Gravity. Steps means Agent.ai (most of the time).
  3. Is my buyer me, or is my buyer procurement? Self-serve means Gravity. Procurement-led means Agent.ai if it fits that motion.
  4. Will my monthly bill scale with usage? If predictable bundled pricing matters, lean Gravity. If you prefer paying for what you use, Agent.ai's free to browse. credit-based pricing on agent runs may fit better.

The framework is biased, of course. Gravity is the product I am building. The point of writing it out is that the bias is visible. You can run the same four questions and ignore my recommended branch; the framework still works.

When Agent.ai is the right choice

When Gravity is the right choice

Migration: what changes if you switch

A marketer who started on Agent.ai with templates often outgrows them once they need something specific to their company. Gravity is where the bespoke version goes.

  1. Inventory the Agent.ai templates you actually use.
  2. For each, write the outcome in one sentence in your own words.
  3. Run the sentence on Gravity.
  4. Compare result quality.
  5. Cut over recurring jobs.

The biggest migration surprise tends to be how few jobs actually fit cleanly on either side. Most teams end up with a mix: a handful of recurring outcome-shaped jobs on Gravity, and a handful of category-specific jobs on Agent.ai. The fight between "all in on one tool" and "use the right tool for each job" rarely ends with "all in." Plan for the hybrid from day one and the migration is undramatic.

Common mistakes buyers make

From the conversations I have had with operators picking between these two categories, three mistakes show up over and over:

  1. Buying for a one-off and getting stuck. The first task always looks one-off. Then it recurs. Buyers who chose a tool optimised for single sessions wake up six weeks later with a manual prompt habit and a quietly growing bill.
  2. Confusing intelligence with action. Both Agent.ai and Gravity use strong models. The model is not the differentiator. The differentiator is what happens between prompt and result. Asking "which has the smarter AI?" is the wrong question; both are smart enough.
  3. Skipping the pricing model question. Free to browse. Credit-based pricing on agent runs. Gravity is bundled. Those two structures behave differently at high usage. Run the math at 10 runs a week and 100 runs a week before committing.

Frequently asked questions

What is Agent.ai?

Agent.ai is a marketplace of pre-built AI agents launched by Dharmesh Shah. The user browses, picks, and runs agents built by the community or the platform team.

Is Agent.ai a fit for technical teams?

It can be, but the marketplace model is most useful when the templates fit the task. Technical teams often outgrow templates quickly.

How is Gravity different from a marketplace?

Gravity does not give you a catalog. The sentence is the spec, and the agent is composed for that specific outcome.

Is Gravity for marketers?

Yes, marketers are one of the strongest fits, because marketing work tends to be specific and recurring.

Which is cheaper at scale?

Gravity, once you run more than a few agents weekly. Credit-based pricing rewards low usage and punishes habitual users.

Three takeaways before you close this tab

  1. Catalog vs sentence. Two different first-time experiences. Buyers should pick the one that matches their style.
  2. Templates have a ceiling. For any work specific to your business, the template will miss the point.
  3. Recurring jobs prefer flat pricing. A founder running ten agents a week wants a bundle, not a credit meter.

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