[shhdwi]

Parts 5 to 7 of the learned-skills stack, landing together. Parts 6 (#659) and 7 (#665) were merged into this branch so CI runs once on the whole thing against main. Their descriptions explain those parts.

• Part 5 (below): the look-back in trail init, the review screen, and the skills hook handlers.
• Part 6 (feat(skills): wire skills into the hooks and the CLI, on by default #659): wires it all into trail init and the hooks, and turns skills on by default. There's no trail skills on step.
• Part 7 (feat(skills): learnings and skills never repeat or contradict each other #665): learnings and skills don't repeat each other. Each hook gives one answer, and the skill offer comes before the save ask at Stop.

---

Part 5 of 6 of the learned-skills stack. Base: part 4.

What it adds:

• The look-back (init/sessions.ts, transcript.ts, look-back*.ts, miners.ts, candidates.ts, howtos.ts). It reads the person's own typed messages from past Claude Code sessions about the repo, with no model, and finds what came up on two or more days: preferences, guardrails and repeated jobs.
• The review screen and its keys (init/review-tty.ts), keep and handover (init/keep.ts, handover.ts), and replays of a past run to build a skill from it (init/replay-runs.ts).
• The skills part of each hook: session start, prompt, Stop, PostToolUse on Bash, and walls (claude/start-skills.ts, prompt-skills.ts, stop-skills.ts, post-bash.ts, walls-hook.ts).

Nothing calls any of it yet. trail init and the hooks switch to it in the last part.

What to look at:

• init/look-back-mine.ts: what is read, and what is skipped (headless runs, scratch folders, old sessions).
• init/keep.ts: nothing is kept without the person's pick.
• The hook handlers: each fails open, so a part that throws adds nothing.

🤖 Generated with Claude Code

[trailhq-graft]

🌱 graft blast radius

5 areas changed → 15 areas can be affected. 105 dependent symbols, depth 2.
Tests: 5 areas updated their tests.
Tag: @anirudhkumar-nanonets — 16 of 20 areas · @Frankie-Xu — Context Building, Bash Pre-Processing · Marcelo Caporale — Telemetry

flowchart TB
  A0(("Note Repository<br/>25 symbols"))
  A1(("Graph Building<br/>17 symbols"))
  A2(("Installation Records<br/>12 symbols"))
  A3(("Host Initialization<br/>9 symbols"))
  A4(("Skill Lessons<br/>6 symbols"))
  AX(("10 smaller areas<br/>36 symbols"))
  classDef reached fill:#D9EDF3,stroke:#3AA7C9,stroke-width:1.5px,color:#0E313C;
  class A0,A1,A2,A3,A4 reached;
  classDef tail fill:#EEF2F3,stroke:#9AA4A9,stroke-width:1px,color:#3A4247;
  class AX tail;

Loading

Can be affected	Symbols	Nearest hop	Reached from
Note Repository	25	src/notes/branches.ts:L1-L357 branches.ts — imports, depth 1	Initialization Discovery, writeJsonAtomic
Graph Building	17	src/graph/extract-cache.ts:L217-L227 writeExtractCache — calls, depth 1	writeJsonAtomic
Installation Records	12	src/init/install-record.ts:L50-L74 fileSha — calls, depth 1	Initialization Discovery
Host Initialization	9	src/hosts/init.ts:L53-L119 runHostsInit — calls, depth 1	Claude Integration, writeJsonAtomic
Skill Lessons	6	src/skills/value-line.ts:L203-L218 ledgerTail — calls, depth 1	Initialization Discovery, writeJsonAtomic
MCP Server	6	src/mcp/server.ts:L1-L156 server.ts — imports, depth 1	writeJsonAtomic, Telemetry Tracking
9 smaller areas	30	Telemetry, Context Building, Bash Pre-Processing, …	see below

Who knows this code — 3 people across 20 areas

Area	Who knows it
writeJsonAtomic · changed	@anirudhkumar-nanonets — 67 commits, last today
Claude Integration · changed	@anirudhkumar-nanonets — 34 commits, last today
Telemetry Tracking · changed	@anirudhkumar-nanonets — 15 commits, last today
Skills Compilation · changed	@anirudhkumar-nanonets — 1 commit, last 9d ago
Note Repository · affected	@anirudhkumar-nanonets — 4 commits, last today
Graph Building · affected	@anirudhkumar-nanonets — 30 commits, last 9d ago
Host Initialization · affected	@anirudhkumar-nanonets — 6 commits, last 7d ago
MCP Server · affected	@anirudhkumar-nanonets — 13 commits, last 2d ago
…12 further areas

Ownership is git history over each area's own files, weighted towards recent work (120-day half-life). Merge commits and bots are dropped, and you are dropped from your own PR. A name with no @ has no GitHub handle in its commit email — tag them by hand, or add a .mailmap entry. A suggestion from history, not a CODEOWNERS rule.

All 105 dependent symbols, grouped by area

Note Repository — 25 symbols in 12 files

• src/notes/branches.ts:L1-L357 — branches.ts (imports, depth 1)
  2: * Teammates' pushed branches: which files each one changes, and the learnings
• src/notes/branches.ts:L297-L309 — maybeRefreshBranches (calls, depth 1)
  297: export function maybeRefreshBranches(repo: string, now = Date.now(), maxAgeMs = REFRESH_MS): boolean {
• src/notes/branches.ts:L202-L241 — refreshBranches (calls, depth 1)
  203: repo: string,
• src/notes/home.ts:L1-L523 — home.ts (imports, depth 1)
  2: * Where a repo's personal learnings and takeaways live: on this machine, under
• src/notes/home.ts:L326-L341 — ensureRepoHome (calls, depth 1)
  326: export function ensureRepoHome(start: string, env: NodeJS.ProcessEnv = process.env): { place: RepoPlace; created: boolean } {
• src/notes/home.ts:L292-L301 — findRepoPlace (calls, depth 1)
  292: export function findRepoPlace(start: string, env: NodeJS.ProcessEnv = process.env): RepoPlace {
• src/notes/home.ts:L509-L522 — rememberRepo (calls, depth 1)
  509: export function rememberRepo(dir: string, env: NodeJS.ProcessEnv = process.env, now = Date.now()): void {
• src/notes/memory-notes.ts:L161-L169 — memoryBody (calls, depth 1)
  161: export function memoryBody(note: Pick<MemoryNote, "body">): string {
• src/notes/memory-notes.ts:L62-L64 — memoryDirs (calls, depth 1)
  62: export function memoryDirs(repo: string, home: string = homedir()): string[] {
• src/notes/memory-notes.ts:L1-L280 — memory-notes.ts (imports, depth 1)
  2: * Learnings from the notes Claude Code keeps for this repo on this machine
• src/notes/memory-notes.ts:L252-L279 — finishMemoryRead (calls, depth 1)
  253: repo: string,
• src/notes/ask-notes.ts:L15-L22 — attachNotes (calls, depth 2)
  15: export function attachNotes(r: AskResult, repo: string): AskResult {
• src/notes/ask-notes.ts:L1-L23 — ask-notes.ts (imports, depth 2)
  2: * Puts past sessions' notes next to a query's results, for every surface that
• src/notes/credit.ts:L1-L92 — credit.ts (imports, depth 2)
  2: * How trail credits a learning in what an agent says: a token count short
• src/notes/every-repo.ts:L1-L89 — every-repo.ts (imports, depth 2)
  2: * Every-repo personal learnings (design 1.0, P21, R6): learnings that hold
• src/notes/find-notes.ts:L1-L62 — find-notes.ts (imports, depth 2)
  2: * Which learnings to show next to a query's results.
• src/notes/lesson-index.ts:L1-L132 — lesson-index.ts (imports, depth 2)
  2: * D117 (4): the lesson learnings in a folder, through an index keyed by each
• src/notes/memory-notes.ts:L190-L212 — memoryCandidates (calls, depth 2)
  190: export function memoryCandidates(repo: string, opts: { home?: string; offered?: Set<string> } = {}): MemoryCandidate[] {
• src/notes/memory-notes.ts:L112-L127 — memoryNotes (calls, depth 2)
  112: export function memoryNotes(repo: string, home: string = homedir()): MemoryNote[] {
• src/notes/memory-notes.ts:L220-L222 — offeredMark (calls, depth 2)
  220: function offeredMark(repo: string): string {
• src/notes/note-gate.ts:L1-L215 — note-gate.ts (imports, depth 2)
  2: * What `trail note` checks before it saves a learning for the team: that a
• src/notes/replace.ts:L1-L41 — replace.ts (imports, depth 2)
  2: * `trail note --replaces <id>`: which learning a new one replaces, and what
• src/notes/targets.ts:L1-L105 — targets.ts (imports, depth 2)
  2: * Where a session's learning goes: the repos it changed, with the files it
• src/notes/team-check.ts:L99-L111 — knownText (calls, depth 2)
  99: export function knownText(repo: string): KnownText {
• src/notes/team-check.ts:L1-L134 — team-check.ts (imports, depth 2)
  2: * Whether something `trail init` found is fit to offer as a team learning:

Graph Building — 17 symbols in 11 files

• src/graph/extract-cache.ts:L217-L227 — writeExtractCache (calls, depth 1)
  221: writeJsonAtomic(path, cache, true);
• src/graph/fingerprint.ts:L87-L103 — writeFingerprint (calls, depth 1)
  92: const files: Record<string, Print> = {};
• src/graph/workspace.ts:L564-L604 — federateGrep (calls, depth 1)
  569: ): { result: GrepResult; coverage: string } {
• src/graph/build.ts:L1-L473 — build.ts (imports, depth 2)
  2: * `graph` — build `.context/graph.json` from a code repository.
• src/graph/build.ts:L204-L472 — buildGraph (calls, depth 2)
  210: // Enumerate once: source extraction, scope discovery, and Go module
• src/graph/cards.ts:L1-L322 — cards.ts (imports, depth 2)
  2: * Tier-2 "wiring cards" — the passive-channel surface of the wiring graph.
• src/graph/check.ts:L1-L216 — check.ts (imports, depth 2)
  2: * `checkGraph` — is the committed `graph.json` still in sync with the code?
• src/graph/extract-cache.ts:L1-L228 — extract-cache.ts (imports, depth 2)
  2: * Per-file memo for Tier-1 extraction — `<outDir>/.cache/extract.json`.
• src/graph/fingerprint.ts:L1-L197 — fingerprint.ts (imports, depth 2)
  2: * The cheap "has the working tree moved?" probe that gates the pre-query rebuild.
• src/graph/refresh.ts:L1-L275 — refresh.ts (imports, depth 2)
  2: * `ensureFreshGraph` — the pre-query gate that keeps retrieval honest.
• src/graph/root.ts:L1-L46 — root.ts (imports, depth 2)
  2: * Where "here" is when a query names no directory. An agent session — or a plain
• src/graph/seed.ts:L1-L229 — seed.ts (imports, depth 2)
  2: * `seedGraph` — give a linked git worktree the graph its parent checkout already has.
• src/graph/traverse-cli.ts:L1-L244 — traverse-cli.ts (imports, depth 2)
  2: * CLI wiring for `graft callers` and its `--direction` / `--depth` flags.
• src/graph/workspace-cli.ts:L104-L113 — runWorkspaceAsk (calls, depth 2)
  108: opts: { limit?: number; source?: boolean; full?: boolean; in?: string; json?: boolean },
• src/graph/workspace-cli.ts:L1-L161 — workspace-cli.ts (imports, depth 2)
  2: * CLI print/exit wrappers + per-child build orchestration for workspace
• src/graph/workspace-cli.ts:L115-L132 — runWorkspaceGrep (calls, depth 2)
  119: opts: { ignoreCase?: boolean; fixed?: boolean; json?: boolean },
• src/graph/workspace.ts:L1-L726 — workspace.ts (imports, depth 2)
  2: * Workspace federation — a "workspace" is a parent directory that holds two or

Installation Records — 12 symbols in 4 files

• src/init/install-record.ts:L50-L74 — fileSha (calls, depth 1)
  58: fd = openPlain(path);
• src/init/keep-list.ts:L35-L70 — linesFrom (calls, depth 1)
  35: export function linesFrom(path: string, opts: { from?: number; bytes?: number }): Array<{ line: string; offset: number }> | null {
• src/init/init-record.ts:L379-L398 — walk (calls, depth 2)
  379: const walk = (dir: string, parts: string[]) => {
• src/init/init-record.ts:L307-L317 — readInitRecord (calls, depth 2)
  307: export function readInitRecord(repoKey: string, env?: NodeJS.ProcessEnv): InitRecord {
• src/init/install-record.ts:L96-L99 — initLeftIt (calls, depth 2)
  96: export function initLeftIt(files: InstallFiles | null, checkout: string, rel: string): boolean {
• src/init/install-record.ts:L129-L143 — recordInstall (calls, depth 2)
  129: export function recordInstall(snap: InstallSnap, env: NodeJS.ProcessEnv = process.env): string[] {
• src/init/install-record.ts:L120-L126 — snapInstall (calls, depth 2)
  120: export function snapInstall(checkout: string, rels: string[], env: NodeJS.ProcessEnv = process.env): InstallSnap {
• src/init/install-record.ts:L77-L93 — readInstallRecord (calls, depth 2)
  77: export function readInstallRecord(checkout: string, env?: NodeJS.ProcessEnv): InstallFiles | null {
• src/init/keep-list.ts:L161-L203 — afterList (calls, depth 2)
  161: export function afterList(path: string, list: { offset: number; via: 'init-call' | 'handover' }, env: NodeJS.ProcessEnv = process.env): AfterList | null {
• src/init/keep-list.ts:L108-L144 — findList (calls, depth 2)
  109: { list: ListAt | null; cut: number | null } | null {
• src/init/keep-list.ts:L210-L224 — typedLine (calls, depth 2)
  210: export function typedLine(ref: { t: string; o: number; s: string }, env: NodeJS.ProcessEnv = process.env): string | null {
• src/init/prefs.ts:L244-L277 — repoWordsOf (calls, depth 2)
  244: export function repoWordsOf(checkout: string, programs: Iterable<string> = []): Set<string> {

Host Initialization — 9 symbols in 5 files

• src/hosts/init.ts:L53-L119 — runHostsInit (calls, depth 1)
  54: repo: string,
• src/hosts/plan.ts:L69-L95 — planInit (calls, depth 1)
  69: export function planInit(repo: string, opts: { home?: string; ids?: string[] } = {}): HostPlan[] {
• src/hosts/retract.ts:L370-L520 — targets (calls, depth 1)
  370: function targets(repo: string, opts: RetractOpts): Target[] {
• src/hosts/antigravity.ts:L43-L61 — installAntigravitySkill (calls, depth 2)
  43: export function installAntigravitySkill(home: string, name: Brand = 'graft'): ConfigWrite[] {
• src/hosts/plan.ts:L1-L101 — plan.ts (imports, depth 2)
  2: * What `graft init` *would* write, computed before anything is written.
• src/hosts/registry.ts:L1-L186 — registry.ts (references, depth 2)
  2: * Registry of AI coding hosts Graft can write instructions for.

…44 further symbols not listed.

Test signal per changed area — 5 ✓

Reached = a node under a test path has a resolved edge into the changed symbol. It undercounts anything called indirectly — through a CLI, a spawned process or a dynamic import — so read a low ratio as “look here”, never as a coverage gate.

• ✓ writeJsonAtomic — 37 of 91 reached · 34 test files changed here: test/claude-hook-timeouts.test.ts, test/claude-hooks-fail-open-all.test.ts, test/claude-init.test.ts, test/claude-pre-bash-fail-open.test.ts, test/claude-pre-bash-wiring.test.ts, test/claude-settings-merge.test.ts, test/claude-state.test.ts, test/cli-meta.test.ts, test/cli-picker.test.ts, test/cli-status-codex.test.ts, test/graft-to-trail.test.ts, test/hosts-codex-hooks-2.test.ts, test/hosts-codex-hooks.test.ts, test/hosts-codex-trust.test.ts, test/hosts-cursor-hooks.test.ts, test/search-user-regexp.test.ts, test/trace-gate-file.test.ts, test/trace-typed.test.ts, test/trail-check-gate.test.ts, test/trail-check-learning-edits.test.ts, test/trail-check-local.test.ts, test/trail-cloud.test.ts, test/trail-cold-start.test.ts, test/trail-edit-overlap.test.ts, test/trail-init-layout.test.ts, test/trail-learning-schema.test.ts, test/trail-name.test.ts, test/trail-nudge.test.ts, test/trail-prompt-activity.test.ts, test/trail-text-safety.test.ts, test/trail-upload-names.test.ts, test/trail-upload-safety.test.ts, test/trail-words.test.ts, test/util-state-atomic.test.ts
  • not reached: warnUnsupportedExtensions, queryRoot, parseTabs, afterAsk, runCheckCommand, runNoteCommand, runInitCommand, wireTarget, …46 more
• ✓ Initialization Discovery — 44 of 177 reached · 37 test files changed here: test/agent-trust-merge-1b.test.ts, test/claude-hooks-1b-review-trust.test.ts, test/claude-hooks-1b.test.ts, test/init-b6-review.test.ts, test/init-bounds-review.test.ts, test/init-candidates.test.ts, test/init-claude-call.test.ts, test/init-days.test.ts, test/init-disk-review.test.ts, test/init-fold-lessons.test.ts, test/init-howtos.test.ts, test/init-keep-cli-review.test.ts, test/init-keep-cli.test.ts, test/init-keep-gate-1b.test.ts, test/init-keep-shell-noise.test.ts, test/init-keep.test.ts, test/init-lab-sdk.test.ts, test/init-look-back-home.test.ts, test/init-lookback-hook-taint.test.ts, test/init-lookback.test.ts, test/init-miners.test.ts, test/init-name-call.test.ts, test/init-name-review.test.ts, test/init-prefs-near-repeat.test.ts, test/init-refusal-reasons.test.ts, test/init-relay-review.test.ts, test/init-relay-words.test.ts, test/init-replay.test.ts, test/init-run.test.ts, test/init-screen-review.test.ts, test/init-screen.test.ts, test/init-subrange-review.test.ts, test/init-team-rows.test.ts, test/init-trust-review.test.ts, test/init-uncompiled-record.test.ts, test/learnings-link-1b.test.ts, test/trail-cold-start.test.ts
  • not reached: dateOf, guardrailItems, of, preferenceItems, skillItems, v1Hash, askClaude, finish, …125 more
• ✓ Claude Integration — 32 of 136 reached · 57 test files changed here: test/agent-trust-merge-1b.test.ts, test/claude-codex-post-bash.test.ts, test/claude-copy-dashes.test.ts, test/claude-format.test.ts, test/claude-hook-layers.test.ts, test/claude-hook-timeouts.test.ts, test/claude-hooks-1b.test.ts, test/claude-hooks.test.ts, test/claude-host-standdown.test.ts, test/claude-init.test.ts, test/claude-post-bash-walls.test.ts, test/claude-pre-bash-fail-open.test.ts, test/claude-pre-bash-skills.test.ts, test/claude-pre-bash-wiring.test.ts, test/claude-pre-bash.test.ts, test/claude-prompt-private.test.ts, test/claude-settings-merge.test.ts, test/claude-shim-resolve.test.ts, test/claude-start-skills-1b.test.ts, test/claude-stop-moments.test.ts, test/claude-stop.test.ts, test/claude-tally.test.ts, test/d117-words-lessons-1b.test.ts, test/graft-to-trail.test.ts, test/hosts-trail.test.ts, test/regex-linear-time.test.ts, test/session-metrics.test.ts, test/skills-agent-trust.test.ts, test/skills-anchors-wide-journeys.test.ts, test/skills-anchors-wide-review.test.ts, test/skills-bound-values.test.ts, test/skills-check-readonly.test.ts, test/skills-credit-1b-review.test.ts, test/skills-gated-retry.test.ts, test/skills-held-notice.test.ts, test/skills-lesson-fixtures.ts, test/skills-moments-review.test.ts, test/skills-prompt-attacks.test.ts, test/skills-prompt.test.ts, test/skills-save-gate-asked.test.ts, test/skills-save-parent-folder.test.ts, test/skills-session-start.test.ts, test/skills-ship-credit.test.ts, test/skills-words-1b.test.ts, test/start-kept-notice-race.test.ts, test/start-kept-race-child.ts, test/trace-multiturn.test.ts, test/trail-init-layout.test.ts, test/trail-init-upgrade.test.ts, test/trail-learning-on-touch.test.ts, test/trail-learnings-committed.test.ts, test/trail-note-ask.test.ts, test/trail-notes.test.ts, test/trail-prompt-notes.test.ts, test/trail-start-learnings-place.test.ts, test/trail-text-safety.test.ts, test/trail-words.test.ts
  • not reached: learnings, learningsHere, total, graftJson, readStdin, checkStaleCount, handleToolUse, learningsOnTouch, …96 more
• ✓ Telemetry Tracking — 7 of 9 reached · 8 test files changed here: test/claude-hooks-1b.test.ts, test/claude-hooks-skills.test.ts, test/claude-post-bash-walls.test.ts, test/claude-start-skills-1b.test.ts, test/telemetry-contract.test.ts, test/telemetry-gate.test.ts, test/telemetry-skills-2.test.ts, test/trail-upload-safety.test.ts
  • not reached: trim, track
• ✓ Skills Compilation — 31 of 141 reached · 20 test files changed here: test/claude-journeys-3.test.ts, test/cli-skills-2.test.ts, test/cli-skills-report-1b-review.test.ts, test/cli-skills.test.ts, test/init-fold-lessons.test.ts, test/learnings-link-1b-review.test.ts, test/skills-agent-trust.test.ts, test/skills-anchors-wide-journeys.test.ts, test/skills-anchors-wide.test.ts, test/skills-fixtures.test.ts, test/skills-follow-learnings.test.ts, test/skills-follow-words.test.ts, test/skills-gated-retry.test.ts, test/skills-learning-steps.test.ts, test/skills-own.test.ts, test/skills-person-codex.test.ts, test/skills-save-gate.test.ts, test/skills-settings.test.ts, test/skills-validate.test.ts, test/trail-skills.test.ts
  • not reached: binsNear, cliCall, forgetSkillLesson, initDraftCommand, learningFiles, lessonCommand, one, readLearning, …102 more

76 test suites also reference this code

99 symbols, kept out of the diagram and the table so they cannot crowd out the areas a reviewer has to look at.

• test/app-review-process.test.ts
• test/ask-fusion.test.ts
• test/ask-index.test.ts
• test/ask.test.ts
• test/blast-render.test.ts
• test/blast-viz.test.ts
• test/claude-guard-review.test.ts
• test/claude-shim-template.test.ts
• test/claude-statusline.test.ts
• test/context.test.ts
• test/front-matter.test.ts
• test/generic-extract.test.ts
• test/graph-go.test.ts
• test/graph-incremental.test.ts
• test/graph-invariants.test.ts
• test/graph-refresh.test.ts
• test/graph-scopes.test.ts
• test/graph-workspace-include-dir.test.ts
• test/graph-write.test.ts
• test/hosts-antigravity.test.ts
• …56 more

⚠️ 4 changed files not in the graph (README.md, TELEMETRY.md, docs/github-app.md, test/fixtures/skills/trail/SKILL.md) — no parser claims the extension, or the index predates the file.

_{graft blast · origin/main...HEAD · depth 2 · 304 changed files}

Open the interactive graph → — click an area to see its dependent symbols at file:line.