What is an agentic SDLC?

An agentic SDLC is a software lifecycle where agents do much of the work — planning, building, reviewing — and people decide what’s worth building, and whether it worked.

It changes where the hard part sits. Writing the code is no longer it.

The bottleneck moved

Code got cheap. The queue moved to either side of it.

Agents can turn a request into working code in minutes. But the steps around the code didn’t speed up with it. Work now waits before the build, for someone to say clearly what it’s for, and after it, for review, validation and release.

queueIntentWhat are we building, and why?
queueSpecWhat does done look like?
fastBuildAgents write the code in minutes.
queueReviewIs this what was meant?
queueValidateDoes it hold up?
queueReleaseCan it ship together?
queueOutcomeDid it work?

The step agents made fastWhere work now waits

So the useful measure isn’t how much code was written. It’s the time from an intent to a change you know is right.

The real cost

The worst waste is building the wrong thing.

It always was. Agents just get there sooner, and keep going: every hour of building on a wrong premise makes it harder to turn back.

“There is surely nothing quite so useless as doing with great efficiency what should not be done at all.”
— Peter Drucker

What it needs

What an agentic SDLC needs to build the right thing

Intent made explicit

The why, the outcome and what done looks like, written down before anything is built.

The premise challenged

Someone, or something, attacks the idea before the team commits to it.

Checks at every step

Plans, reviews and releases checked as they happen, not saved for the end.

Results that come back

What shipped is checked against what was meant, and that shapes the next decision.

Where onMain fits

onMain isn’t an agent. It’s the guardrails they work inside.

Bring your own agents. onMain checks the idea before anything is built, and the results after release, so product and engineering are always on the same page.

Not another agentonMain writes no code and calls no model. Your agents, and your people, work through it.
Product and engineering, one pageThe idea, the plan, the review and the release live in one record both sides read.
Dial it up or dial it backEach guardrail is a gate you turn on or off, starting from a preset.

See how it works How onMain is different →

Idea stated, premise testedProduct
Plan challenged before the buildEngineering
Work checked and reviewedEngineering
Released together, cleanlyEngineering
Outcome checked against intentProduct

Questions

Common questions

Is onMain an agent?

No. onMain doesn’t write code or call a model. It’s the lifecycle your agents and people work through, and the guardrails they’re held to.

Which agents work with it?

Any agent that connects over the MCP. You choose the agents; onMain holds them to the same gates.

Do I have to turn every gate on?

No. Start from a preset and dial it up or back, per firm and per product.

Is it only for engineers?

No. It’s for product and engineering together: product decides what’s worth building and whether it worked; engineering builds and lands it.

Know it’s the right thing before it’s built.

Choose a way of working, connect your agents, file the first idea.

Free for one product and one person.