OSTEON

A Claude Code plugin for the OSTEON framework.

Agentic development made code cheap. Correct context is now the expensive part. OSTEON gives context the same discipline code already has: version control, review gates, decay detection and provenance.

Every project gets one knowledge repository, called its BONE. It holds no product code. It holds the project's constitution, its decisions, the contracts between its modules, the state of the running system as last verified, and the project's own skills.

What ships

• 15 skills, listed below. Plugin skills are namespaced, so each one is invoked as /osteon:<name>, for example /osteon:bone-adr. Claude also loads them on its own when a request matches a skill's description.
• The BONE scaffold (plugins/osteon/scaffold/): the template and bone-init.sh, which /osteon:bone-init runs. Every BONE it creates carries its own hooks: a decay check wired to SessionStart, and provenance, tier and attestation lints with a self-test.
• One SessionStart hook. It runs the decay check only in a BONE that does not carry its own hook, and is silent everywhere else, including every BONE the scaffold created.

Prerequisites

• Claude Code with plugin support.
• A POSIX shell with git, sed, grep, awk and find. The scaffold and every hook are POSIX sh with no other dependency.
• For osteon-ossification-delivery-teaching only: Python 3.9 or later and a Chromium-family browser, for its PDF and screenshot steps.

Install

/plugin marketplace add osteonlabs/osteon-framework
/plugin install osteon@osteon

To try it without installing, from a clone of this repository:

claude --plugin-dir ./plugins/osteon

Start a BONE

1. Run /osteon:bone-init with a project name, a short skill prefix and an empty target directory:

   /osteon:bone-init --project "City Library Lending" --prefix cll --dir ~/city-library-lending-bone
   

   The skill can also ask you for them. It creates the repository, makes the genesis commit and prints numbered next steps. Nothing is pushed; add --remote <url> to set origin.

2. Open Claude Code in the new directory. The decay check runs at session start. On a fresh scaffold it reports the state uninitialised; that reading is correct until the knowledge base has real content and a sealed baseline.

3. Work the printed next steps: fill MANIFEST.yaml, write the first state records, open a decision record for each live question, then run /osteon:bone-curator for the first curation pass.

4. Returning to the project later, or onboarding someone new: /osteon:bone-onboard.

The skills

Starting and operating a BONE:

Skill	Use it to
/osteon:bone-init	Scaffold a new BONE for a project.
/osteon:bone-onboard	Get up to speed on a project, or return to one after a gap.
/osteon:bone-adr	Write, amend or supersede a decision record.
/osteon:bone-contract	Create or version the contract for a seam between two modules.
/osteon:bone-curator	Audit the knowledge base and change it with per-item approval.
/osteon:bone-git	Branch, commit and open change requests the project's way.
/osteon:bone-review	Review a change against the project's own bar.
/osteon:bone-standup	Keep the daily brief, debrief and continuity journal.

The framework and the ossification method:

Skill	Use it to
/osteon:osteon-framework	Trace where a rule comes from, and name a way of working.
/osteon:osteon-ossification-planner-project-daily	Plan a multi-repository project as one dated cycle per day.
/osteon:osteon-ossification-plan-starter	Decide whether a plan may start, one question at a time.
/osteon:osteon-ossification-plan-implementor	Run a gated plan as lanes in one session.
/osteon:osteon-single-session-ossification	Run a large plan as one session with subagents.
/osteon:osteon-ossification-delivery-teaching	Report what a cycle delivered to people outside it.
/osteon:osteon-capture	Record what a session learned, without writing a rule.

Tiers: one owner per fact

Tier	Lives at	Owns
T0 org	this plugin	The methodology: how to record a decision, version a contract, run the curation loop.
T1 project	the project's BONE	The project's facts, decisions, contracts and procedures, in prefix-named skills.
T2 repository	a code repository's own CLAUDE.md	Conventions true inside that one repository.

A fact lives at exactly one tier, the narrowest that fully owns it. Lower tiers reference; they never copy. When a fact could sit at two tiers, place it by what would change it, not by topic. The personal tier, your own preferences and memory, sits outside: a BONE never governs or cites it.

References to material not in this plugin

The skills were written against the full OSTEON specification and a larger set of units. Some pointers therefore name material this plugin does not ship. None of them is needed to use a skill: each rule is stated in full where it applies, and the pointer records where it comes from.

• B-<number>, D-<letter>.<number>, "SPEC section" and "SPEC Appendix" references cite requirements in the OSTEON specification, which is not yet published. Read them as provenance.
• bone-skills/README.md was the source repository's README. Where a skill says to install the T0 library from it ("Installing T0"), installing this plugin already did that. Its "Enabling commit signing" section is ordinary git configuration (gpg.format, user.signingkey, commit.gpgsign). Its "section 4" held the authoring rules for T0 units; a src: null entry in a meta.yaml that points there means only that T0 has no project ledger to cite.
• bone-curate-fast, bone-team, bone-user and osteon-research-unit are units that are not in this release. bone-curate-fast is the in-session fast curation pass; until it ships, route that work to /osteon:bone-curator. bone-team owns a team tier and bone-user the personal tier; neither is needed for a single project. osteon-research-unit maintains the OSTEON research papers and depends on private data.

Paper and citation

OSTEON is described in the preprint "Superintelligent Software Engineering: Governance That Scales with Capability", arXiv:2610.31306 [cs.SE], 2026, DOI 10.48550/arXiv.2610.31306.

If you use OSTEON or build on its ideas, cite the paper. To cite this software release, use its Zenodo DOI, 10.5281/zenodo.23436020. CITATION.cff carries both, with the paper as the preferred citation; GitHub shows it as "Cite this repository".

License

The content is licensed under CC BY 4.0, so any use or adaptation must credit the author. The scripts are licensed under MIT. See LICENSE.

Building this repository

plugins/osteon/skills/ and plugins/osteon/scaffold/ are generated by build.sh from the source repositories and are never edited by hand. Skills that exist only in the plugin, such as bone-init, live in plugin-src/skills/. Every build must pass its gates: a names denylist over every published file, no em dash, valid skill frontmatter, and one version across plugin.json, marketplace.json and CITATION.cff. The source commits of each build are recorded locally in .build/provenance, which is not published.