mxdecision

name	mxDecision
description	Use when the user says "/decision", "/mxDecision", "document decision", "write an ADR", "record a decision", "architectural decision", "ADR", or otherwise wants to capture a significant technical choice made in the conversation. Creates or updates Architecture Decision Records (ADRs) via MCP-Tools in the mxLore knowledge DB; maintains supersedes chain and status transitions.
allowed-tools	Read, Write, Edit, Grep, Glob

/mxDecision — Create ADR (AI-Steno: !=forbidden →=use ⚡=critical ?=ask)

Context: ALWAYS as subagent(Agent-Tool) !main-context. Result: max 20 lines. Tokens ⚡: mx_create_doc/mx_update_doc body >300 words → assemble in this subagent, !echo to parent. mx_detail server default = 600 tokens.

ADR-Agent. Creates decisions as ADR in Knowledge-DB via MCP.

Init

1. CLAUDE.md→**Slug:**=project_slug. ∅slug→?user
2. mx_ping()→OK=MCP-mode | Error=Local(docs/decisions/ADR-NNNN-<slug>.md+Warning→/mxMigrateToDb)

Input

Title from command argument. ∅arg→?user.

⚡ Title clamp: server ClampTitle=255. The final title will be ADR-NNNN: <Title> — the ADR-NNNN: prefix eats ~12 chars, so keep the title content under ~240 chars. Truncate locally and warn if longer.

⚡ Slug derivation + normalization (slug is derived from title for the local file path; MCP path uses auto-numbering): Read ~/.claude/skills/_shared/slug-normalization.md.

Workflow

1) ADR Number

MCP: Auto-number via mx_create_doc(doc_type='decision') — no separate query needed. Local: docs/decisions/index.md→highest number+1

2) Create ADR

Template → ~/.claude/skills/mxDecision/assets/adr-template.md (6 sections: Status/Date meta, Context, Decision, Consequences with Advantages/Disadvantages/Follow-ups subsections). ⚡ Absolute path — subagent CWD is the project root, not the skill dir, so a relative assets/… read silently fails. If the template file is unreadable, fall back to a minimal inline skeleton (Context + Decision + Consequences) and warn the user.

Status values: accepted=decided in chat | proposed=still to be confirmed | superseded=replaced by another ADR | deprecated=no longer in use

⚡ ADR numbering contract: the NNNN placeholder in the template title is resolved AFTER mx_create_doc returns the new doc_id — the server auto-assigns the number. Workflow: (a) create with placeholder title ADR-NNNN: <Title>; (b) read returned doc_id; (c) immediately mx_update_doc(doc_id, content-with-resolved-title, change_reason='Assign ADR number'). Never compute the number locally — that would race with parallel creates. ⚡ Visibility window: between (a) and (c) there is a brief window (<1s typical) where a concurrent mx_search reader sees the literal placeholder title ADR-NNNN:. This is acceptable — the window is short, the doc is correctly tagged doc_type='decision', and the mx_update_doc in (c) finalizes the title atomically.

MCP: mx_create_doc(project, doc_type='decision', title='ADR-NNNN: <Title>', content) — ⚡ Slug is auto-generated server-side from the title via GenerateSlug(Title) at mx.Tool.Write.pas:541-542, then the ADR-number prefix is prepended at mx.Tool.Write.pas:579-585. The server param slug= does not exist on mx_create_doc and is silently ignored. Ensure the title is canonical and unique; the server handles dedup via ClampSlug + retry-with-suffix (mx.Tool.Write.pas:588-599).

Local (Fallback): ensure docs/decisions/ exists (mkdir -p docs/decisions); if index.md absent create it with a minimal header, otherwise APPEND the new entry. Write docs/decisions/ADR-NNNN-<slug>.md + warning. ⚡ This fallback violates ADR-0004 "local docs/ = only CLAUDE.md+status.md" — only used when MCP is down; re-sync via /mxMigrateToDb once MCP is back.

3) Existence Check for References + Duplicate Guard

⚡ Slug collision check first: mx_search(project, doc_type='decision', query='<slug>', status='active', include_content=false, limit=5). Verify each result's slug field matches the normalized input EXACTLY (mx_search uses full-text — foo can match foo-v2). Only an exact-slug active hit goes to Update path; ∅exact match → proceed with New.

⚡ TOCTOU guard: after step 2 creates the new ADR, re-query once with the same filter. If >1 active ADR with this exact slug now exists, a parallel run raced us — warn user and keep the oldest, archive the new one (or ask).

Referenced docs lookup: for each reference surfaced in step 4 (assumes / rejected_in_favor_of / caused_by / supersedes), use mx_search(project, doc_type='decision,spec,plan,note', query='<ref-title-or-id>', status='active', include_content=false, limit=5) to resolve target doc_id. ⚡ Exact-verify step: mx_search is full-text and may tokenize hyphens, so foo-bar can match foo-bar-v2. For each candidate, verify the returned slug or title matches the caller's reference EXACTLY before proceeding; on ambiguous matches, ask the user to pick a doc_id. Only call mx_detail if you need the body for an Update; never for a simple relation lookup.

4) Create Relations (MCP only)

After mx_create_doc — 4 optional questions to user (each skippable).

⚡ Skip grammar: treat any of no / n / nein / skip / - / empty line / EOF as "skip this question and continue". Anything else is treated as the answer. Case-insensitive. Parser must be robust — never loop on empty input, never treat "" as an empty-title assumption doc.

Question	Relation	Action
Assumptions that could change?	assumes	mx_create_doc(doc_type='assumption')+mx_add_relation
Alternatives evaluated+rejected?	rejected_in_favor_of	mx_create_doc(doc_type='note')+mx_add_relation
What caused this? (doc_id or text)	caused_by	mx_add_relation (or create+relate)
Supersedes existing ADR(s)? (one or more doc_ids)	supersedes	Loop: for each old ADR → mx_add_relation + step 5 supersede update

⚡ mx_add_relation direction: source_doc_id is ALWAYS the new ADR, target_doc_id is the referenced doc (assumption/note/spec/plan/old ADR). Never reverse. The server dedupes duplicate edges, so no pre-check required. ⚡ Param names: the server expects literally source_doc_id and target_doc_id (NOT source / target). Confirmed at mx.Tool.Write.Meta.pas:365-366.

⚡ Supersedes loop: an ADR can supersede multiple predecessors (e.g. merging two competing approaches). Iterate over ALL supplied old doc_ids — do not stop at first. Each iteration: add relation + flip old ADR status (see step 5).

Auto-scan for motivating spec/plan: after the 4 questions, run mx_search(project, doc_type='spec,plan', query='<ADR title>', status='active', limit=5) and filter results to avoid full-text noise:

• Require relevance score ≥ 0.5 (or the server's default threshold) OR title-token overlap ≥ 2 tokens (split title on whitespace, count shared tokens with each candidate title after lowercasing)
• Cap at top 3 after filtering
• If ∅candidates pass the filter → skip silently (do not ask)
• If candidates pass → surface as: Spec/Plan candidates that may have motivated this ADR: [list]. Enter doc_id to link, or 'no' to skip:. ⚡ Require explicit doc_id entry — never a yes/no on an ambiguous full-text match, to avoid corrupting the graph with wrong-target motivated_by edges.
• User-confirmed doc_id → mx_add_relation(source_doc_id=<new ADR>, target_doc_id=<doc_id>, relation_type='references'). ⚡ Param names are literally source_doc_id/target_doc_id (mx.Tool.Write.Meta.pas:365-366). ⚠ NOTE: motivated_by is NOT in the server's allowed relation_type list (mx.Tool.Write.Meta.pas:376-380 → leads_to, implements, contradicts, depends_on, supersedes, references, caused_by, rejected_in_favor_of, assumes). Use references until a motivated_by enum is added server-side.

5) Status Transition

⚡ Required before every mx_update_doc: mx_detail(doc_id, max_content_tokens=0) to fetch the full body — the server default (600 tokens) silently truncates, and writing the truncated content back causes SILENT DATA LOSS. The 600-token default is for queries, not edits. This is the #1 hazard for ADRs because superseded ADRs often have long Context sections.

⚡ Status whitelist: auto-transition only runs when the current MCP status is active. Skip for already-archived, superseded, deprecated. Check current status via mx_detail before flipping.

⚡ Server-clamp limits: Read ~/.claude/skills/_shared/mcp-clamp-limits.md. Note: title prefix ADR-NNNN: eats ~12 chars from the 255 budget. Keep change_reason concise; long values silently truncate.

Editing rules (preserve audit history):

• Flip status line: match the current status line with a case-insensitive regex (?i)^\*\*Status:\*\*\s*(active|accepted|proposed|implemented|superseded|deprecated) — users routinely type Accepted/PROPOSED/mixed case. Replace in place with the new status (preserving the line prefix); do NOT remove the line. Literal lowercase-only matching is a silent no-op bug (same family as mxSpec [resolved] case-sensitivity).
• Mark follow-up done: flip - [ ] to - [x] (or - [X]); do NOT remove the line.
• Remove obsolete follow-up: annotate as - [x] ~~original~~ (dropped) — never delete silently.

Supersedes chain (step 5a): For each supersedes relation created in step 4, update the OLD ADR. ⚡ Two-phase contract:

• Phase A — Read: for each old doc_id call mx_detail(old_doc_id, max_content_tokens=0) (the 600-token default truncates and writing it back causes silent data loss).
• Phase B — Flip: for each old ADR call mx_update_doc(old_doc_id, content, status='archived', change_reason='Superseded by ADR-NNNN') with the case-insensitive content status flip to superseded + appended **Superseded by:** ADR-NNNN (doc_id=<new_doc_id>) footer. Status flips ONE WAY ONLY (old ADR → superseded); never flip the new ADR backwards. Skip any old ADR whose current DB status is not active (already archived/superseded/deprecated) and warn — do not re-flip. Collect a per-iteration outcome {old_doc_id, prev_status, new_status, error?} for every iteration.
• Partial-failure recovery: on a failed iteration do NOT abort the loop and do NOT roll back successful flips — continue the remaining old doc_ids and surface a combined report at the end (N/M old ADRs archived as superseded. Failed: [list with errors]. Completed: [list].). The supersedes relations from step 4 stay valid; the user reconciles the failures manually.
• Order: the new ADR (this skill's mx_create_doc) is ALREADY created at step 2. The supersede-flips here run AFTER the new ADR exists but BEFORE the skill returns success — so the chain is: (1) create new ADR, (2) add supersedes relations [step 4], (3) flip every old ADR's status [Phase A+B above], (4) report. If you ever invoke this skill in a mode where the new ADR is not yet created, the supersedes-flips MUST wait until after creation (or after explicit partial-failure acknowledgement).

⚡ change_reason clamp safety: the Superseded by ADR-NNNN string is ~28 chars, safe. If the caller wants to append a rationale, enforce a local 497-char cap and append ... if longer (see _shared/mcp-clamp-limits.md).

Follow-ups completed (step 5b): Scan H3 ### Follow-ups under H2 ## Consequences (or first matching H2 carrying Consequences / Konsequenzen). Skip fenced code blocks. Drop strikethrough lines containing ~~ AND (dropped). See ~/.claude/skills/mxDecision/references/followup-scope.md for the canonical algorithm. Outputs M (total live follow-ups) and N (completed).

1. M == 0 → skip transition (no follow-ups to check).
2. Status whitelist: only transition when current MCP status is active.
3. M > 0 AND N == M AND DB-status == active:
   • mx_detail(doc_id, max_content_tokens=0) → full body
   • Case-insensitive flip: **Status:** accepted → **Status:** implemented
   • mx_update_doc(doc_id, content, status='archived', change_reason='All follow-ups completed')
   • Output: ADR #<doc_id> archived — fully implemented
4. Mixed (N < M): ∅change, info only: <N>/<M> follow-ups completed

Proposed→Accepted (step 5c): When user confirms a proposed decision in chat:

1. mx_detail(doc_id, max_content_tokens=0) → full body
2. Content: **Status:** proposed → **Status:** accepted
3. mx_update_doc(doc_id, content, change_reason='Confirmed by user') (no status='archived' — accepted ADRs stay active at DB level)

Status mapping (content-level vs DB-level):

Content Status	DB Status	Meaning
proposed	active	Decision drafted, not yet confirmed
accepted	active	Confirmed, in force
implemented	archived	All follow-ups done, ADR complete
superseded	archived	Replaced by a newer ADR
deprecated	archived	No longer in use, not replaced

Rules

• ⚡ Only verified knowledge from chat !invent. ∅context→?user !reconstruct
• ⚡ Related: mx_search verify BEFORE mx_add_relation
• !rewrite/delete existing ADRs. Concise: Context+Decision 2-5 sentences each
• MCP preferred, local=fallback

Completion

Output (max 20 lines, truncate aggressively):

1. doc_id + ADR number
2. Brief confirmation (1-2 sentences summarizing the Decision section, truncated to 120 chars)
3. Up to 3 relations created (show target title + doc_id only)
4. Recommendations:
   • /mxSpec if the ADR needs a matching specification for the implementation details
   • /mxPlan <slug> to derive an implementation plan from the accepted ADR
5. If active workflow → name next step

If more relations exist than shown, append ... and N more (see mx_detail <doc_id>).