ahel
Start free

Investigating unexpected changes

SkillDocs & knowledge

Use when unexpected changes appear on your branch or worktree — commits you did not make, amended or force-pushed history, or a working tree that contradicts your memory — to reconstruct who did what and decide how to proceed.

Available today. Use it from your connected AI after setup.

Connect ahel once, and every AI you use reads what you have installed.

Then ask your AI: use the Investigating unexpected changes skill

What this skill tells your AI

The instructions your AI receives, as published by scriptedalchemy/tracedecay in plugin/skills/investigating-unexpected-changes/SKILL.md and read by ahel’s review.

Parallel agents share branches and worktrees. Real sessions have hit this and guessed: one Claude session found three of its branches amended under it and called it "auto-merged... a repository watcher"; a Cursor session saw a test file it "didn't write but which passes" and spent turns on blind git log trying to explain it. Blind git archaeology cannot name the actor. TraceDecay correlates every session to the branches, worktrees, and commits it touched, so you can attribute the change instead of theorizing. Do that before you react.

Establish what changed

Pin the objective facts first; do not act on a hunch.

  1. Local ground truth: git status, git log --oneline -20, and git reflog -20 (reflog survives amends and resets — it shows HEAD moving even when git log looks clean).
  2. Semantic shape of the delta:
    • Uncommitted working-tree drift → tracedecay_commit_context (changed symbols, file roles, recent commit style) to see what moved without reading raw diffs.
    • Branch moved vs. where you expected → use Git's live merge-base and git diff --name-only <base>...<head> as the file boundary, then pass those paths to tracedecay_diff_context. Treat tracedecay_branch_diff as a summary only after its commits/files agree with that live boundary; never act on a stale graph snapshot alone.

Attribute it

Turn "what changed" into "who changed it" with the session-git correlation index.

  1. tracedecay_sessions_for (git_ref: branch | worktree | commit, value, optional since / until) lists every session correlated with the artifact. Query the surprising commit sha first, then the branch or worktree if the commit is unattributed.
  2. Read the relation on each returned session:
    • produced — that session made the commit (the actor you are looking for).
    • observed — that session only saw it (a bystander, useful for timeline but not authorship).
    • unclassified legacy rows have no relation and still match; treat them as candidates, not proof, and corroborate with the session's messages below.
  3. Attribution is span-based, so a session that switched branches mid-run is credited only for the spans it actually held — a produced hit is trustworthy even across branch churn.

Read the acting session's context

Once you have the acting session id, recover why it made the change.

  1. tracedecay_message_search (query, plus branch / commit filters, or parent_session_id) surfaces what the actor was told to do and what it reported — search the commit sha or the touched file names.
  2. tracedecay_lcm_grep with scope: "session" and that session_id returns bounded raw-message snippets for the one session; scope: "all" is the cross-session default.
  3. Heed the capped_sessions disclosure: a broad (scope: "all") grep can cap how many sessions it scans and say so. When the acting session may have been capped, rerun with scope: "session" and its id for complete results before concluding.

Decide

With the actor, their intent, and the delta in hand, choose:

  • Compatible and wanted → adopt it: rebase or fast-forward onto the new HEAD and continue.
  • Conflicting or unwanted → coordinate: the produced session id and its goal tell you whom to reconcile with rather than force-pushing over live work.
  • Ambiguous ownership → do not overwrite. A force-push over another agent's produced commit destroys unmerged work.

If a durable ownership convention emerges (for example "branch codex/* is owned by the Codex worktree"), record it with tracedecay_fact_store so the next session inherits it — see tracedecay:project-memory.

If tools are deferred or MCP fails

  • Deferred (names listed without schemas): load once with ToolSearch — select:tracedecay_sessions_for,tracedecay_commit_context,tracedecay_diff_context,tracedecay_branch_diff,tracedecay_message_search,tracedecay_lcm_grep (one batched call) — then call normally.
  • MCP error / timeout / disconnect: same tools via shell — tracedecay tool sessions_for --args '{"git_ref":"commit","value":"<sha>"}', tracedecay tool commit_context, tracedecay tool diff_context, tracedecay tool branch_diff, tracedecay tool message_search, tracedecay tool lcm_grep (see tracedecay:using-the-cli). Never query .tracedecay databases directly; never fall back to blind git archaeology when the correlation index can name the actor.

Deliverable

Do not end without: the objective delta (which commits/files/symbols changed and how HEAD moved), the attributed actor (session id + relation, or an explicit "unattributed" when no session correlates), that session's intent from its messages, and the chosen action (adopt / coordinate / hold). Report any tracedecay_metrics: line.

Signals

GitHub stars
73
Forks
5
Last commit
Sep 2026
Advanced
Catalog kind
skill
Gateway key
investigating-unexpected-changes
Source
github.com/scriptedalchemy/tracedecay

github.com/scriptedalchemy/tracedecay

More in Docs & knowledge

canvas-design
Skill · anthropicsdoc-coauthoring
Skill · anthropicstheme-factory
Skill · anthropicsagent-architecture-audit
Skill · affaan-mbrand-voice
Skill · affaan-mck
Skill · affaan-m