onesie

What it is

onesie is a command line tool that asks a System One model, such as Jev, one question about a piece of text and gives back an answer a script can use: a probability, a chosen option or an exit code. No prompt to tune and no prose to parse.

echo 'I was charged twice for my order' | onesie 'who should handle this' --pick billing,shipping,technical -o raw
# billing

Three question shapes

• Yes or no: onesie 'is this urgent' returns the probability of yes.
• Pick: --pick billing,shipping,technical chooses one option, with its confidence.
• Rate: --rate low,medium,high chooses a level on an ordered scale.

--ask names several questions and sends them in one request, and -f loads saved questions from a file.

Gates on exit codes

--assert turns an answer into an exit code, so a judgment can stop a pipeline:

onesie -f shell-safety -q --state 'git status'               # exit 0: pass
onesie -f shell-safety -q --state 'rm -rf ~'                 # exit 1: fail, so block
onesie -f shell-safety -q --state 'echo hello > notes.txt'   # exit 7: unsure, so hand off to a person

--abstain-if gives a gate a middle ground: answers too close to call exit 7 instead of a yes or a no, so a person decides only the hard cases. Any other exit code is an error, so a gate fails closed.

Thresholds from evidence

onesie calibrate runs your questions over your own labelled examples and reports what every cut would catch, with AUC, precision and recall per question, so a gate's threshold comes from data:

destroys, yes/no: labelled 40, 16 yes, 24 no, 0 errors. AUC 1.00

--require turns that report into a CI check, so a model or prompt change that weakens a gate fails the build.

Four calibrated starter sets ship built in: moderation, personal-data, prompt-injection and shell-safety. onesie questions lists them beside your own.

Built for pipelines

• Streams: read JSONL, CSV, TSV or lines from stdin, answer each record in order, and work on live input such as tail -f.
• Spreadsheets stay spreadsheets: -o csv --merge writes your rows back with the answers added as columns.
• Long batches: --id names each record, --resume picks up an interrupted run where it stopped, and repeated records are asked once.
• Concurrency: -j sets how many records are in flight, and retries back off on rate limits.
• Formats: json, csv, tsv, table, markdown, bare values or one raw answer.

Test without a key

• Mocks: --mock answers from a fixture file instead of the API, so gate scripts can be tested in CI for free, errors and timeouts included.
• Dry runs: --print-request shows the exact request body without sending it.
• Cache: --cache stores responses on disk and answers a repeated request from them.

Providers and local models

onesie works with TypeSafe, OpenRouter, Berget, Levanto and Cloudflare. Profiles keep each provider's settings, and keys stay in the OS keychain unless you choose a file. Point ONESIE_BASE_URL at your own server that speaks a provider's API, and no key is needed.

In GitHub Actions

setup-onesie installs a verified binary in one step, and its run mode asks a question and sets pass, fail or unsure as an output, with no bash:

- uses: frodi-karlsson/setup-onesie@v1
  env:
    TYPESAFE_API_KEY: ${{ secrets.TYPESAFE_API_KEY }}
  with:
    file: shell-safety
    state: ${{ github.event.pull_request.title }}

For coding agents

A Claude Code plugin ships skills that teach an agent when to reach for onesie, how to write a gate that fails closed, how to stream a file and how to calibrate, plus a session hook that checks onesie is installed and a key resolves.

/plugin marketplace add frodi-karlsson/onesie
/plugin install onesie@onesie

Install

brew install frodi-karlsson/tap/onesie
# or
curl -fsSL https://raw.githubusercontent.com/frodi-karlsson/onesie/main/install.sh | sh
# or
go install github.com/frodi-karlsson/onesie/cmd/onesie@latest

Then store a key with onesie profile create work --provider typesafe, which prompts for it, and ask your first question:

echo 'the build is red again' | onesie 'is this urgent'

Every release is signed and carries build provenance. onesie is open source under the MIT license.