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.
The point of this post is not to pick a winner. It is 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 this comparison
The most expensive buying mistake is choosing a tool whose category does not match the job: a workflow builder for what is really a chat assistant problem, or a chat assistant for what is really a scheduled agent problem. The tools are good. The category is wrong.
So this head-to-head is written as category framing, not a feature list. The question to answer first is "which shape of work am I doing?" Once that is clear, the product choice falls out almost automatically. The comparison between Agent.ai and Gravity below is 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:
- Discovering an existing agent that already does the task you want.
- Buyers who prefer browsing a catalog to writing prompts.
- Marketing and growth use cases with broad templates.
- Community contributions, since other people build agents you can run.
- A low-commitment way to see what AI agents can do.
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
| Capability | Agent.ai | Gravity |
|---|---|---|
| Discovery model | Browse catalog | Write a sentence |
| Customisation | Tweak parameters of a pre-built agent | Sentence is the spec |
| Best fit | Common tasks with templates | Specific tasks for your business |
| Time to first run | Minutes if a template matches | About 60 seconds for any task |
| Composability | Chain agents from the catalog | Single agent does the chain |
| Pricing | Free tier plus credits | Pay per use, credits at $1 / 1,000 |
| Best for | Marketers exploring AI | Founders 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
- Agent.ai: Free to browse. Credit-based pricing on agent runs.
- Gravity: Pay per use. Credits priced at $1 for 1,000, charged only when an agent runs. No infrastructure to manage, agents built and maintained for you.
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 once you count infrastructure and engineer hours, not just the platform sticker.
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.
- 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.
- Do I want to describe the outcome, or assemble the steps? Outcome means Gravity. Steps means Agent.ai (most of the time).
- Is my buyer me, or is my buyer procurement? Self-serve means Gravity. Procurement-led means Agent.ai if it fits that motion.
- Do I want a finished outcome, or a template to adapt? A finished outcome from one sentence means Gravity. Browsing and tweaking a catalog agent means Agent.ai.
The framework is biased, of course. Gravity is the product behind this blog. The point of writing it out is that the bias is visible. You can run the same four questions and ignore the recommended branch; the framework still works.
When Agent.ai is the right choice
- You are new to AI agents and want to see examples.
- A template in the catalog already does what you need.
- You like community-built agents and crowd-sourced ideas.
- You run agents irregularly, not on a schedule.
When Gravity is the right choice
- You know the outcome you want, in a sentence.
- No template in any catalog will fit, because your work is specific.
- You run agents on a recurring schedule.
- You want a finished result from one sentence, with no infrastructure to manage.
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.
- Inventory the Agent.ai templates you actually use.
- For each, write the outcome in one sentence in your own words.
- Run the sentence on Gravity.
- Compare result quality.
- 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
Across conversations with operators picking between these two categories, three mistakes show up over and over:
- 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.
- 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.
- Skipping the pricing model question. Agent.ai is free to browse, with credit-based pricing on agent runs. Gravity is pay per use, charged only when an agent runs. Both track usage, so 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?
It depends on the work. Both charge per use, so cost tracks usage on either side. Gravity tends to win when the task is specific to your business and you would rather not browse a catalog or manage infrastructure.
Three takeaways before you close this tab
- Catalog vs sentence. Two different first-time experiences. Buyers should pick the one that matches their style.
- Templates have a ceiling. For any work specific to your business, the template will miss the point.
- Specific work beats templates. A team running ten agents a week wants outcomes built for its business, not catalog parameters to tweak.
Sources
- Agent.ai. "Official product page." agent.ai
- Gravity. "Why we bet against workflow platforms in 2026." /blog/why-i-bet-against-workflow-platforms-2026/
- Gravity. "AI agent vs workflow automation." /blog/ai-agent-vs-workflow-automation/