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Bernstein vs Skyvern: quick decision guide

Skyvern adapter: drives an existing Skyvern server over HTTP.

Page built on 2026-09-18 from data/adapters-meta.json. Every claim below links to its primary source.

Install both

Skyvern

No install command recorded in the bernstein adapter source as of 2026-09-18.

Bernstein

pipx install bernstein

Apache-2.0. Deterministic Python scheduler.

Feature matrix

CapabilitySkyvernBernstein
Install methodNot recordedpipx install bernstein
LicenseNot recordedApache-2.0
AuthenticationNot recordedPer-agent credential scoping (no shared key)
Multi-agent orchestrationOne agent in a terminalSkyvern plus 40+ other adapters in parallel worktrees
MCP supportNot measuredYes
Parallel-safe in worktreesNot measuredYes (designed around git worktrees)
HMAC-chained audit logNoYes (RFC 2104 SHA-256 chain in .sdd/)
Deterministic schedulerNot applicable (single-agent CLI)Yes (Deterministic Python scheduler)

Adapter source: src/bernstein/adapters/skyvern.py

Verifiable facts

The brief for this surface requires at least three facts that a reader can verify against a primary source. The list below is built from the bernstein adapter source and, when available, the upstream project's own pages.

  1. Bernstein ships a Skyvern adapter at src/bernstein/adapters/skyvern.py that wraps the upstream CLI as one of 42 routable agents. [source: bernstein adapter source, as of 2026-09-18]
  2. Bernstein is an open-source Multi-agent orchestrator licensed Apache-2.0, with a deterministic Python scheduler that routes work across CLI agents in parallel git worktrees. [source: bernstein repo, as of 2026-09-18]
  3. Bernstein records lineage and a replay journal on every run; with the audit log enabled it also writes an HMAC-SHA256 chained record under .sdd/ that lets a reviewer replay every routing and quality-gate decision. [source: bernstein repo, as of 2026-09-18]

Where Skyvern fits in Bernstein

Bernstein registers Skyvern under the slug "skyvern" and the registry name "skyvern". The adapter source lives at src/bernstein/adapters/skyvern.py in the bernstein repo and was last touched at build time 2026-09-18. The Skyvern adapter file is 251 lines and 9,116 bytes long, fingerprinted a3490ace60676722 (first 16 hex chars of SHA-256). No upstream GitHub repository is recorded in the bernstein adapter for Skyvern; refer to the upstream vendor's documentation when auditing. The bernstein adapter file for Skyvern does not yet carry a "Last verified against upstream" line; this means the adapter still tracks an unpinned upstream binary. Bernstein routes tasks to Skyvern when its pass rate on similar work clears the configured threshold, otherwise the deterministic Python scheduler picks a different adapter from the 40+ adapter catalog.

Adapter source excerpt

The module docstring of the Skyvern adapter, as it stands in the bernstein repo. Punctuation is normalised for the web; the wording is the author's. Length: 690 characters.

Skyvern adapter: drives an existing Skyvern server over HTTP. Skyvern is a maintained, self-hostable, goal-driven browser agent. The operator starts the Skyvern server separately (``skyvern server --port 8000``); this adapter connects to it over HTTP and drives runs through its REST surface. This adapter subclasses :class:`bernstein.adapters.computer_use.ComputerUseAdapter` so it inherits the computer-use contract (output mode ARTIFACT, POLL_PTY event channel, per-task isolation, and capability gating via :attr:`is_computer_use`). We do not import the Skyvern Python SDK or vendor any of its code. The integration is HTTP-only so the AGPL-3.0 upstream stays out of our dependency set.

Adapter telemetry

Registry nameskyvern
Adapter classSkyvern
Source filesrc/bernstein/adapters/skyvern.py
Source file size251 lines, 9,116 bytes
Source SHA-256a3490ace6067672262d4828877539b2bf4ced2d7cf961627938d50c1deba13b4
Category bucketcloud-sdk-family
Upstream repoNot derivable from adapter source
Upstream homepageNot recorded
Last verified upstreamNo "Last verified" line in adapter source
Operator-curated overlayNo (programmatic page)

When to pick which

Choose Skyvern

Reach for Skyvern when the work is a single thread that fits one agent: in a single-process terminal session, designed for single-instance use per repo. Auth model is configured per upstream docs. You skip the orchestrator round-trip and get the smallest possible surface between you and the model.

Choose Bernstein

Wrap Skyvern under Bernstein when the goal splits into parallel tasks, when you want an HMAC-chained audit log on every routing decision, or when a deterministic Python scheduler (no LLM picking who runs what) is a hard requirement. Bernstein wires the cloud SDK adapter to the same audit chain the local CLI adapters use, so one regulator review covers both.

FAQ

Does Bernstein replace Skyvern?

No. Bernstein wraps Skyvern as one of 40+ CLI adapters and routes tasks to it based on per-task pass-rate history. Skyvern keeps running unchanged; Bernstein decides when it gets work.

Can I run Skyvern alongside other agents in the same repo?

Yes. Each agent runs in its own git worktree under .sdd/worktrees/{session_id}, so file edits never collide. Bernstein merges results back to the trunk only after the configured quality gates (lint, types, tests) pass.

Is this comparison page handwritten?

No. The template is fixed; every fact and every link is pulled from the bernstein adapter source in the master branch and (when available) the upstream project's own pages. The data extractor lives at scripts/gen-compare-data.mjs. No LLM writes the prose.