YC Spring 2026 (P26) company

ReasonBlocks

The runtime layer that makes AI agents cheaper and more reliable

b2bb2b2 public signals

About ReasonBlocks

ReasonBlocks is the runtime layer that makes AI agents cheaper and more reliable. We correct agent reasoning and compress tokens mid-run, with gains compounding across runs. On SWE-Bench pro we have seen a 52% token reduction and 42% accuracy lift.

Public traction evidence

Each signal links to the public source used for attribution.

  1. X

    Paul Graham post about ReasonBlocks cutting LLM token costs by about half

    Paul Graham described doing office hours with a startup that cuts companies' LLM token costs by optimizing requests, cutting costs by about half. The official YC Spring 2026 snapshot identifies ReasonBlocks as the runtime layer that makes AI agents cheaper and cites a 52% token...

  2. LinkedIn

    ReasonBlocks | ReasonBlocks (YC P26)

    [Skip to main content](https://linkedin.com/posts/reason-blocks_reasonblocks-activity-7447459083332411392-iQux#main-content)[LinkedIn](https://linkedin.com/?trk=[redacted-public-param]) * [Top Content](https://www.linkedin.com/top-content?trk=[redacted-public-param]) *...