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Introducing Index-O1 ↗

Stay with the hard problem.

Index-O1 is a 576-billion-parameter model for research, writing, planning, software, and decisions that resist a quick answer.

Discover Index-O1
01 / Intelligence

A model for consequential work.

Useful intelligence does more than answer. It examines the premise, keeps track of the evidence, and shows its work.

Index-O1 can work across long, difficult material without losing the argument, the constraints, or the reason the work began.

576B parameters
One focused system
Synapse Foundation Frontier reasoning model / 2026
02 / Capabilities

One intelligence.
Many forms of work.

Four modes of work, held together by one continuous context.

01

Reason

Hold competing ideas, trace consequences, and arrive at a position you can defend.

02

Research

Move from open questions to structured evidence, with the important distinctions intact.

03

Create

Develop writing, strategy, and software from first principle to finished work.

04

Decide

See the whole decision: tradeoffs, unknowns, second-order effects, and the next move.

03 / Principles

Technology with a point of view.

Powerful by design.
Principled by default.

  1. 01

    Private

    Your thinking should remain yours. Privacy is not a setting; it is the foundation.

  2. 02

    Deliberate

    Built to make thought clearer, not attention noisier. No feeds. No engagement loops.

  3. 03

    Honest

    Intelligence includes knowing the edge of certainty—and saying where that edge is.

“
AI should expand the range of human thought, without diminishing human agency.

A new space for serious thought

Meet Index-O1.

Early access is opening gradually for researchers, builders, writers, and teams.