Compare
Bernstein vs Kiro: quick decision guide
Kiro CLI adapter.
Page built on 2026-05-18 from data/adapters-meta.json. Every claim below links to its primary source.
Install both
Kiro
No install command recorded in the bernstein adapter source as of 2026-05-18. See upstream docs at kiro.dev.
Bernstein
pipx install bernsteinApache-2.0. Deterministic Python scheduler.
Feature matrix
| Capability | Kiro | Bernstein |
|---|---|---|
| Install method | Not recorded | pipx install bernstein |
| License | Not recorded | Apache-2.0 |
| Authentication | Not recorded | Per-agent credential scoping (no shared key) |
| Multi-agent orchestration | One agent in a terminal | Kiro plus 41 other adapters in parallel worktrees |
| MCP support | Not measured | Yes |
| Parallel-safe in worktrees | Not measured | Yes (designed around git worktrees) |
| HMAC-chained audit log | No | Yes (RFC 2104 SHA-256 chain in .sdd/) |
| Deterministic scheduler | Not applicable (single-agent CLI) | Yes (Deterministic Python scheduler) |
Adapter source: src/bernstein/adapters/kiro.py | Upstream homepage: kiro.dev
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.
- Bernstein ships a Kiro adapter at src/bernstein/adapters/kiro.py that wraps the upstream CLI as one of 42 routable agents. [source: bernstein adapter source, as of 2026-05-18]
- 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 2026-05-18]
- Bernstein writes an HMAC-SHA256 chained audit log under .sdd/ that lets a reviewer replay every routing and quality-gate decision in a run. [source: bernstein repo, as of 2026-05-18]
Where Kiro fits in Bernstein
Bernstein registers Kiro under the slug "kiro" and the registry name "kiro". The adapter source lives at src/bernstein/adapters/kiro.py in the bernstein repo and was last touched at build time 2026-05-18. The Kiro adapter file is 112 lines and 4,078 bytes long, fingerprinted 05881c31f876100c (first 16 hex chars of SHA-256). No upstream GitHub repository is recorded in the bernstein adapter for Kiro; refer to the upstream vendor's documentation when auditing. The Kiro project's homepage at kiro.dev is the primary source for upstream release notes. The bernstein adapter file for Kiro does not yet carry a "Last verified against upstream" line; this means the adapter still tracks an unpinned upstream binary. Bernstein routes tasks to Kiro when its pass rate on similar work clears the configured threshold, otherwise the deterministic Python scheduler picks a different adapter from the 42-adapter catalog.
Adapter source excerpt
The text below is the verbatim docstring of the Kiro adapter in the bernstein repo, with em-dashes swapped for commas so the voice gate passes. Length: 17 characters.
Kiro CLI adapter.Adapter telemetry
| Registry name | kiro |
|---|---|
| Adapter class | Kiro |
| Source file | src/bernstein/adapters/kiro.py |
| Source file size | 112 lines, 4,078 bytes |
| Source SHA-256 | 05881c31f876100ce2d5d9cbbf5d4b98c13c9d758c28dbd3f1a42bf591fd0bf6 |
| Category bucket | cli-family |
| Upstream repo | Not derivable from adapter source |
| Upstream homepage | kiro.dev |
| Last verified upstream | No "Last verified" line in adapter source |
| Operator-curated overlay | No (programmatic page) |
When to pick which
Choose Kiro
Reach for Kiro 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 Kiro 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.
FAQ
Does Bernstein replace Kiro?
No. Bernstein wraps Kiro as one of 42 CLI adapters and routes tasks to it based on per-task pass-rate history. Kiro keeps running unchanged; Bernstein decides when it gets work.
Can I run Kiro alongside other agents in the same repo?
Yes. Each agent runs in its own git worktree under .worktrees/, 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.