Decision Lifecycle Agent Skill

decision-lifecycle

Author and track ADRs. Routed to when the user invokes /adr "<title>" (author a new ADR) or /adr-status [--adr N] (list ADR health, read-only). Every ADR is user-attributed — this skill never records a decision the user did not explicitly make.

The append-only decision-log format (entry fields, supersession protocol) lives in ${CLAUDE_PLUGIN_ROOT}/includes/smarts/decision-log-format.md. Read it before writing a log line; do not restate it here.

Boundary with decision-variance. This skill owns ADR *authoring* and *status* (/adr, /adr-status) — recording a decision the user has already made, and reporting ADR health. decision-variance owns *arbitration* — detecting variances between artifacts and the scaffold, scoring options via SMARTS, and the decision log itself. The two share the canonical SMARTS reference under ${CLAUDE_PLUGIN_ROOT}/includes/smarts/ (core.md for scoring, decision-log-format.md for the log) and one ADR template (references/adr-template.md); they are one domain split by responsibility, not duplicated. When a decision needs *making* (competing options), route to decision-variance; when it needs *recording* (already decided), stay here.

Pre-flight

Read these, or STOP and surface the gap — never guess a path:

• <project-root>/.codearbiter/decisions/ — the ADR directory and existing records. Create it on first /adr if absent.
• For /adr: confirm the user explicitly authorized this decision and supplied (or confirmed) its content. An ADR is never authored as the disposition of a routine finding.

Phase 1 — Index · gate: BLOCK

Scan <project-root>/.codearbiter/decisions/ for existing NNNN-*.md ADR files. Record each by filename stem (0014-githook-shim-dropin-fail-closed), title, and status. Determine the next sequential number (no gaps) for /adr; for /adr-status this is the working set.

The stem is the identifier; the number is only a sort key. Two ADRs may already share a number — this repository holds two numbered 0014 — so a bare number can name more than one document. Index by stem, and never assume NNNN resolves to one file until you have checked.

Gate: the existing ADRs are indexed by stem and, for /adr, the next number is fixed and unused — a number already taken by an existing stem is not available, even for an unrelated decision.

Phase 2 — Author (/adr) · gate: STOP

Confirm the decision content with the user — context, the decision itself, alternatives, consequences. MUST NOT fill these from inference. Surface any unknown as an inline [CONFIRM-NN] placeholder; do not resolve it by guessing.

Drop the authoring marker first. The pre-write/pre-edit hooks block any write to .codearbiter/decisions/NNNN-*.md unless a fresh authoring marker is present — that block is the mechanism enforcing "ADRs only via /adr" (ORCHESTRATOR §3), so the sanctioned path must arm it itself. Immediately before writing, create the marker at the path the hooks check (project root = git top level):

mkdir -p "$(git rev-parse --show-toplevel)/.codearbiter/.markers"
touch "$(git rev-parse --show-toplevel)/.codearbiter/.markers/adr-authoring-active"

The marker is honored for 30 minutes. Then write <project-root>/.codearbiter/decisions/NNNN-<slug>.md using the canonical ADR template — ${CLAUDE_PLUGIN_ROOT}/routines/decision-lifecycle/references/adr-template.md (the single source of truth for the ADR shape, shared with decompose). Author it with status: proposed. If this decision supersedes an existing one, set supersedes: to that ADR's full filename stem — supersedes: 0014-githook-shim-dropin-fail-closed, never supersedes: 0014 — and leave the prior ADR's file untouched (forward-only chain — do not edit it to add a back-reference).

If the new ADR supersedes only *part* of the prior decision, say which part in the body. supersedes: names a document, not a clause, so a chain may legitimately fork — two ADRs can each supersede different clauses of one predecessor. That fork is correct and must not be "repaired"; only the prose can carry the scope.

After writing the ADR, append a corresponding entry to the decision log per the format in ${CLAUDE_PLUGIN_ROOT}/includes/smarts/decision-log-format.md — Decided by: names the user. Status transitions (proposed → accepted → superseded | rejected) require explicit user instruction; never advance status on this skill's own judgment.

governs: makes the decision live. When an ADR names path globs in governs:, the post-write

hook surfaces a one-line notice on any Write/Edit touching a matching file — "this file is governed

by ADR-NNNN" — so a recorded decision pushes back at edit time instead of waiting for a checkpoint

sweep. Offer the field whenever a decision constrains identifiable files; omit it for decisions

without a file footprint. Globs are fnmatch-style against repo-relative forward-slash paths.

Once the ADR file and its log entry are written (and any user-instructed status edit is applied), remove the marker — it exists only for one authoring pass:

rm -f "$(git rev-parse --show-toplevel)/.codearbiter/.markers/adr-authoring-active"

Gate: the ADR file is written with a real decided-by user attribution, numbered without a gap, and its log entry is appended. An ADR with no user attribution, or authored as the disposition of a finding, does not pass — STOP.

Phase 3 — Status (/adr-status) · gate: BLOCK

Read-only. For each ADR (or the --adr N target), report: stem, title, status, date, and supersession state — found by scanning forward for any later ADR whose supersedes: resolves to it.

Resolve a supersedes: value like this, and never guess:

• The value is a stem → it names that ADR. Done.
• The value is a bare number → collect every stem with that number. Exactly one → it names that ADR. More than one → ambiguous: report it as an error and resolve nothing. Zero → a dangling reference; report that too.
• none (or empty) → no predecessor.

.github/scripts/check_adr_identity.py enforces this same rule mechanically in CI; if it disagrees with this report, the report is wrong.

If a supersession candidate contradicts an accepted ADR with no clear direction, do not pick one — flag it for /conflict.

## ADR Status — YYYY-MM-DD

### Active
- ADR-NNNN-<slug> — <title> — <status> (<date>)

### Superseded
- ADR-NNNN-<slug> — <title> — superseded by ADR-MMMM-<slug>

### Ambiguous supersession
- ADR-NNNN-<slug> — supersedes: <value> names <N> ADRs (<stems>) — unresolved

### Unresolved CONFIRM-NN
- ADR-NNNN-<slug> — [CONFIRM-NN]: <text>

Every ADR is named by its stem, so a shared number never collapses two rows into one. An empty section is marked "None" — not omitted. MAY dispatch decision-challenger (${CLAUDE_PLUGIN_ROOT}/agents/decision-challenger.md) to stress-test an ADR; optional, never forced.

Gate: every indexed ADR appears with its current status and supersession state; no [CONFIRM-NN] resolved; no file modified.

Hard rules

• MUST author an ADR only via /adr with explicit user attribution. MUST NOT author an ADR as the disposition of a routine finding — an out-of-scope finding gets an inline [NEEDS-TRIAGE] marker instead.
• MUST NOT record a decision the user did not explicitly make. "Use your best judgment," "I trust you" are declined.
• MUST NOT resolve a [CONFIRM-NN] placeholder by guessing. Surface it and stop.
• MUST NOT advance an ADR's status without explicit user instruction.
• MUST NOT edit a prior ADR or a prior decision-log entry to add a back-reference — supersession is a forward-only chain; append a new record whose supersedes: names the prior one.
• The never-edit rule protects decision CONTENT, not identifiers. Rewriting what was decided corrupts the record; disambiguating *which document a pointer names* repairs it. Maintainer ruling, 2026-07-25: *"the never edit rule is meant to prevent this situation, not prevent this situation from being fixed."* So a correction that is provably identifier-only — a supersedes: value changed from a number to the stem it already meant — is permissible, and nothing else about the file is. Any such correction MUST be a single-line diff that alters not one word of any decision, MUST be visible in its own commit, and still requires the maintainer-armed adr-authoring-active marker. MUST NOT touch Context, Decision, Alternatives, Consequences, Risks, status:, date:, decided-by:, or title: under this allowance.
• MUST NOT number an ADR with a gap, and MUST NOT reuse a number an existing stem already holds — a shared number makes every bare reference to it ambiguous.
• MUST NOT modify any file under /adr-status — it is read-only.
• MUST NOT force the decision-challenger agent — its dispatch is MAY only.