Internal APIs Are All You Need

Companion docs for the Unbrowse whitepaper.

• Authors: Lewis Tham, Nicholas Mac Gregor Garcia, Jungpil Hahn

• arXiv: 2604.00694

• Canonical PDF: unbrowse-whitepaper.pdf

• Paper draft synced here: April 1, 2026

Important The PDF mixes research results, product behavior and forward-looking economic design. These docs separate the three: what the paper measured, what the hosted Unbrowse service does today, and what is still roadmap.

The short version

Most of the web's value sits behind interfaces built for humans. Websites already call their own internal APIs.

Unbrowse learns those requests once, in a cloud browser, and compiles them into capabilities agents call over HTTP. Later agents skip the browser.

What ships today

Unbrowse is a hosted service (https://unbrowse.ai, closed source) with an open-source client (this repo).

The service:

• records tasks in a cloud browser (patchright) and fulfils the first request while learning it

• compiles recorded sessions or HAR files into learned.* capabilities (harness YAML, unbrowse/v1alpha1)

• replays them over first-party HTTP, with a render fallback for reads HTTP cannot finish

• verifies outcomes: HTTP 200 is not success

• keeps a public registry of scrubbed, re-verified read-only site tools, each site also an MCP server and an OpenAPI document

• keeps logins in a password manager the model never reads, signs in on replay and reuses sessions

• bills only verified calls: 500 a month free, then $10 per 10,000

• routes plain-language tasks with Jev, with a deterministic fallback

The client is @unbrowse/sdk and a thin CLI over the service's REST API (/api/v1); agents use the remote MCP (/mcp).

Not built: per-route pricing, contributor payouts, validator markets, attestation.

Pages

• Unbrowse In Plain English

• What Is Unbrowse?

• The Problem

• Mental Models

• How It Works

• For Technical Readers

• For Investors

• Public Registry and Maintenance

• Credential Sovereignty

• Key Concepts

• System Today

• Paper vs Product Status

• Evaluation and Benchmarks

• Coming Soon

Where to start

• Shortest explainer: Plain English.

• Architecture and evidence: For Technical Readers.

• Market and business: For Investors.

• Current state, piece by piece: System Today.

• Strict audit of the paper: Paper vs Product Status.

• Numbers and where they come from: Evaluation and Benchmarks.

Citation

@misc{tham2026internal,
  title = {Internal APIs Are All You Need},
  author = {Lewis Tham and Nicholas Mac Gregor Garcia and Jungpil Hahn},
  year = {2026},
  eprint = {2604.00694},
  archivePrefix = {arXiv},
  note = {Official Unbrowse whitepaper}
}