Augustus

Augustus — named for Augustus De Morgan (1806–1871), mentor and professor of William Stanley Jevons — is an agent skill for placing typed probabilistic judgment (the Jev-class of System One models) using mathematical, logical, and algorithmic mental models. It applies across AI, software, business, knowledge work, and life — not only SWE. TypeSafe Jev is the documented exemplar (Choice, Score, Noul), not the monopoly. Formal methods are one pillar. Exact work stays in code or policy; the model owns narrow judgment; never launder a Noul as a proof.

Companion, not replacement, to the official typesafe-ai skill. That skill owns Jev integration contracts; Augustus owns the design judgment: which pillar, family, and classical method map, what the objective implies for fail-open vs fail-closed, and what experiment would prove a design wrong. Not a TypeSafe-only how-to.

The skill

• .agents/skills/augustus/SKILL.md — working protocol + decision-design card
• .agents/skills/augustus/references/mental-models.md — cross-domain frames (EU, abstention, VOI, MCDA, SDT, search/control, Leveson, NATM/snap-fit/Norman); not SWE-only
• .agents/skills/augustus/references/judgment-class.md — the class (Jev exemplar, not monopoly): open heads (Laya, encoder DeBERTa, LoRA distill), constrained-AR (TypeAR, pcdServer), announced decision-model (Watch), GLiNER/GLiClass species (locate vs categorize vs local multi-head), listwise vs decision objectives, vision scoring, when-to-use axes, agent-architecture portents
• .agents/skills/augustus/references/formal-methods.md — judgment vs proof ownership; Alloy Analyzer vs Apalache (finder ≠ BMC ≠ inductiveness); TLA+/Quint/P/NuSMV/PRISM/Event-B/mCRL2/KeYmaera; Dafny/JML/Frama-C/SPARK/ITP; DST trio (Antithesis hypervisor, Resonate HQ durable-async Lean+oracle+SDK, PufferLib env+seed); TOCTOU-of-Noul, soundness theater, AI×FM harms (Hillel, Cauli); NATM/snap-fit/Norman/ Leveson/Kent/Shirky
• .agents/skills/augustus/references/formal-semi-formal.md — one-screen alias of the FM pillar
• .agents/skills/augustus/references/mixed-architecture.md — default placement: judgment-class model + LLM + code; preference lint; provider (Jev default / other family with self-eval)
• .agents/skills/augustus/references/applied-mappings.md — context sieve, exact-text keep/drop, env triage, moderation/ranking, skill routing
• .agents/skills/augustus/references/faq.md — "just classification", stack replacement, Jev vs open head vs encoder vs LoRA vs constrained AR, GLiNER vs GLiClass vs CLIP, LLM-as-judge, not-another-how-to
• .agents/skills/augustus/references/mappings.md — classical-method mappings with boundaries, counterexamples, acceptance tests (including Hypothesis cards §6–§19 — promote only with a test that ran)
• .agents/skills/augustus/references/validation.md — design gate, eval recipes, Jev-for-skills (routing, self-monitoring, testing, modularity, frontmatter), and Eval & hill-climb (jevals hygiene + Harbor taskset)
• .agents/skills/augustus/references/boundary-audit.md — existing-system insertion: fit test, opportunity map, smallest boundary, red flags
• .agents/skills/augustus/scripts/evaluate_decisions.py — offline evaluator for selective binary decisions (Brier, reliability, threshold/cost sweep)

Plus research/ — the living evidence archive behind the skill, refreshed hourly (see research/README.md).

Install

Claude Code (plugin marketplace, mirrors the official TypeSafe layout):

claude plugin marketplace add 24601/Augustus
claude plugin install augustus@augustus

Any skills-compatible agent (Amp, Codex, Cursor, …):

npx skills add 24601/Augustus --skill augustus

ChatGPT: skills are not a native ChatGPT primitive — paste .agents/skills/augustus/SKILL.md plus the references/ files into a GPT's instructions or a Project's knowledge and it will follow the protocol.

Amp: repo-local .agents/skills/ are discovered automatically.

GitHub topics

jev typesafe typesafe-ai system-one system-one-models structured-output calibrated-confidence ai-agents agent-skills decision-systems reranking beam-search claude-code python llm decision-theory semantic-search agent-workflows mixed-architecture tool-routing skill-routing semantic-lint classification gliclass listwise-ranking vision-scoring open-weights formal-methods model-checking deterministic-simulation decision-theory value-of-information signal-detection mcda calibration alloy apalache pufferlib stamp-stpa

Versioning

See CHANGELOG.md and releases. Current: 0.3.0, written against typesafe-ai/skills v0.5.7 (65a39f3). Re-read live TypeSafe docs before treating that pin as current API behavior.

License

MIT — see LICENSE.