fix(wiki): parseFrontmatterBlock must not treat comments or indented lines as keys

Third review round on PR #126. Two real bugs in the rewrite from the
previous commit:

1. The comment guard the sibling api package's frontmatter parser has
   (strings.HasPrefix(trimmed, "#")) was dropped in this reimplementation.
   A frontmatter comment containing a colon got cut at the colon and
   re-rendered with collapsed internal whitespace.
2. Worse: an indented YAML block-list item containing a colon (e.g. a
   title with a subtitle inside an aliases: list) was misparsed as a
   top-level key/value pair -- strings.Cut doesn't know a line is a
   continuation just because TrimSpace(key) happens to be non-empty.
   Re-rendering then stripped the line's indentation, de-indenting it
   out of the list it belonged to. refreshOwned re-renders this block on
   essentially every non-skipped ingest, so this was the normal path,
   not an edge case.

Checked whether the sibling api/frontmatter.go has the same list-item gap:
it does (same strings.Cut-then-TrimSpace shape, no indentation check) --
not a regression introduced here, a pre-existing latent defect shared
with the package this was modeled on. Filed separately rather than fixed
here (out of scope for this PR, needs its own review).

Fixed by checking indentation BEFORE calling Cut at all -- a line
starting with a space or tab is a continuation line, full stop,
regardless of what it contains -- and restoring the comment guard
verbatim from the sibling.

Flip-tested both guards independently: removing either one turns its
corresponding new test red in isolation; the other stays green,
confirming they're independent fixes, not one masking the other.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

.env.example

@@ -1,7 +1,6 @@
 # Supervisor MCP server
 SUPERVISOR_PORT=3200
 SUPERVISOR_CONFIG_DIR=./config/supervisor
-SUPERVISOR_MODELS_FILE=./config/models.yaml
 
 # LiteLLM gateway (iguana)
 LITELLM_BASE_URL=http://iguana:4000

.gitea/workflows/cd.yml

@@ -81,11 +81,19 @@ jobs:
           git config user.email "cd-bot@d-ma.be"
           git config user.name "CD Bot"
           git add "k3s/apps/supervisor/ingestion-deployment.yaml"
-          git commit -m "chore(deploy): ingestion → ${IMAGE_TAG}"
-          GIT_SSH_COMMAND="ssh -i ~/.ssh/infra_deploy_key -o IdentitiesOnly=yes" \
-            git push
-
-          echo "Infra repo updated: ingestion → ${IMAGE_TAG}"
+          # Idempotent: `git commit` exits 1 on an empty index, so a run that
+          # finds the bump already applied failed the whole job and rang the
+          # CI-red alarm for a deploy that was fine (hyperguild#118). Two
+          # sources of a no-op run: a manual re-run, and the tag-push CI run
+          # that used to shadow the branch-push one for the same sha.
+          if git diff --cached --quiet; then
+            echo "Infra already at ${IMAGE_TAG} — nothing to commit"
+          else
+            git commit -m "chore(deploy): ingestion → ${IMAGE_TAG}"
+            GIT_SSH_COMMAND="ssh -i ~/.ssh/infra_deploy_key -o IdentitiesOnly=yes" \
+              git push
+            echo "Infra repo updated: ingestion → ${IMAGE_TAG}"
+          fi
 
       - name: Trigger Flux reconcile (immediate)
         run: |

.gitea/workflows/ci.yml

@@ -2,8 +2,13 @@ name: CI
 
 "on":
   push:
+    # Branch only. A `v*` tag here points at a commit main already tested, so
+    # the tag push re-ran the whole gate and — because cd.yml keys off "CI
+    # succeeded" — triggered a SECOND full image build and deploy for the same
+    # sha. That second deploy then died on "nothing to commit" (hyperguild#118).
+    # Nothing consumes a tag-triggered run: there is no release workflow, and
+    # cd.yml reads github.sha, not the tag.
     branches: [main]
-    tags: ["v*"]
   pull_request:
     branches: [main]
 

Procfile

@@ -1,2 +1 @@
 ingestion: cd ingestion && INGEST_BRAIN_DIR=../brain INGEST_PORT=3300 INGEST_WATCH_INTERVAL=30 go run ./cmd/server/
-supervisor: SUPERVISOR_CONFIG_DIR=./config/supervisor SUPERVISOR_MODELS_FILE=./config/models.yaml SUPERVISOR_SESSIONS_DIR=./brain/sessions INGEST_BASE_URL=http://localhost:3300 INGEST_SVC_URL=http://localhost:3300 go run ./cmd/supervisor/

README.md

@@ -76,6 +76,46 @@ that prompted the question is answered by naming it here instead.
 Full reasoning, including the reversal trigger: brain
 `wiki/hyperguild/decisions/brain-mcp-stays-in-ingestion-fix-discoverability-by-name`.
 
+## Ingest revises, it does not overwrite
+
+Re-ingesting a source **merges into the page already on disk** rather than
+replacing it. Previously the write was unconditional, so a second ingest of the
+same source discarded everything accumulated since — including hand-written
+sections.
+
+The merge is deliberately asymmetric in the existing page's favour:
+
+| On the page | In the fresh extraction | Result |
+|---|---|---|
+| a section | the same section | **the on-disk version wins** |
+| — | a new section | added |
+| a bullet list (`Sources`, `Key Claims`, …) | more bullets | unioned, no duplicates |
+| an append section (`Open Questions`, `Updates`, …) | more lines | only genuinely new lines appended |
+| frontmatter | frontmatter | **the on-disk frontmatter wins** |
+
+So an extraction can add to a note but never silently rewrite what a human put
+there, which is what makes it safe to run on every ingest rather than behind a
+review gate.
+
+Re-ingesting unchanged content is **byte-identical** — no diff, so brain-sync
+does not commit noise that hides real edits.
+
+Two fields are **generator-owned** and do get refreshed on a revise:
+`last_updated` and `source_hash`. Everything else on disk wins. The boundary is
+an explicit allowlist, so a field nobody has thought about stays human-owned.
+
+## Re-ingesting an unchanged source is skipped
+
+Ingest stores `source_hash` — sha256 of the ingested **body**, frontmatter
+excluded — on the source page. A later ingest of the same source compares it
+first and skips extraction entirely when it matches, reporting the skip rather
+than doing it silently.
+
+Body-only is deliberate: a re-crawl that stamps a new fetch date has not changed
+the source, and treating that as drift would re-extract the corpus every time a
+crawler ran. A missing or unreadable hash always means "extract" — a missed skip
+costs one extraction, a wrong skip loses an update.
+
 ## Phase 1 tools (available now)
 
 | Tool | What it does |

Taskfile.yml

@@ -21,7 +21,7 @@ tasks:
   # ── Development ────────────────────────────────────────────────────────────
 
   start:
-    desc: Start ingestion + supervisor (requires goreman — go install github.com/mattn/goreman@latest)
+    desc: Start ingestion (requires goreman — go install github.com/mattn/goreman@latest)
     cmds:
       - goreman start
 
@@ -32,11 +32,6 @@ tasks:
       - lsof -ti:3200 | xargs kill -9 2>/dev/null || true
       - echo "hyperguild stopped"
 
-  supervisor:dev:
-    desc: Run supervisor MCP server (development)
-    cmds:
-      - go run ./cmd/supervisor
-
   hyperguild:dev:
     desc: Run hyperguild CLI from source (e.g. task hyperguild:dev -- tier)
     cmds:
@@ -67,14 +62,9 @@ tasks:
   build:
     desc: Build all binaries
     cmds:
-      - task: supervisor:build
+      - task: hyperguild:build
       - task: ingestion:build
 
-  supervisor:build:
-    desc: Build supervisor binary
-    cmds:
-      - go build -trimpath -ldflags="-s -w -X main.version={{.VERSION}}" -o bin/supervisor ./cmd/supervisor
-
   ingestion:build:
     desc: Build ingestion server binary
     dir: ingestion
@@ -84,7 +74,7 @@ tasks:
   # ── Quality ────────────────────────────────────────────────────────────────
 
   check:
-    desc: Run all checks (context freshness + lint + test + vet) across all modules
+    desc: Run all checks (context freshness + lint + test + vet + build) across all modules
     cmds:
       # Context sync is skipped under CI, matching dma-cli, gitea-mcp, and the
       # rest of the estate. It is not a preference: context-sync.sh walks UP
@@ -120,6 +110,12 @@ tasks:
       - task: lint
       - task: test
       - task: vet
+      # `build` is in the gate deliberately (hyperguild#120). vet and test walk
+      # ./... , which enumerates the packages that EXIST — so a build target
+      # naming a DELETED package is invisible to both. `task build` pointed at
+      # ./cmd/supervisor for months after that directory was removed, and CI
+      # stayed green the whole time because nothing in check ever built.
+      - task: build
       - task: security:gitleaks
 
   # ── Security ─────────────────────────────────────────────
@@ -173,19 +169,6 @@ tasks:
       - govulncheck ./... || true
       - cd ingestion && go vet ./...
 
-  supervisor:test:smoke:
-    desc: Smoke test supervisor via MCP (requires start running)
-    cmds:
-      - |
-        curl -s -X POST http://localhost:${SUPERVISOR_PORT:-3200}/mcp \
-          -H "Content-Type: application/json" \
-          -d '{"jsonrpc":"2.0","id":1,"method":"tools/list","params":{}}' | jq .
-
-  smoke:routing:
-    desc: Boot the routing pod against live LiteLLM + brain and verify _routing logs land
-    cmds:
-      - bash scripts/smoke-routing.sh
-
   # ── Git / Release ──────────────────────────────────────────────────────────
 
   tag:

config/models.yaml

@@ -1,26 +0,0 @@
-# Model selection — first entry per skill is used.
-# Override per-call by passing model in the MCP tool args.
-# Model names come from LiteLLM /v1/models (host/name format).
-
-default_chain:
-  - iguana/qwen3-coder-next
-
-skills:
-  tdd:
-    chain:
-      - koala/qwen3-coder-30b
-  review:
-    chain:
-      - iguana/devstral
-  debug:
-    chain:
-      - iguana/deepseek-r1-14b
-  spec:
-    chain:
-      - koala/phi4-14b
-  retrospective:
-    chain:
-      - iguana/qwen3-coder-next
-  trainer:
-    chain:
-      - iguana/qwen3-coder-next

ingestion/internal/api/update.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/claim"
 )
 
 // ContentHash returns the lowercase hex sha256 of b. It is the note's
@@ -98,14 +99,47 @@ func UpdateNote(brainDir string, opts UpdateNoteOptions) (relPath, contentHash,
 	}
 	priorHash = ContentHash(prior)
 
+	// A caller may lead opts.Content with its own frontmatter fence to set or
+	// change fields on supersede (e.g. the claim envelope). Split it off
+	// before it reaches the body — left un-split, it would render as a
+	// second, inert `---`-fenced block of literal text rather than taking
+	// effect, and any claim-envelope fields inside it would reach disk
+	// unvalidated (hyperguild#111: the same rule that guards note birth in
+	// writeHallNote must guard a change to the same fields).
+	contentFM, contentBody := parseFrontmatter(opts.Content)
+
 	fm, _ := parseFrontmatter(string(prior))
+	for _, l := range contentFM.lines {
+		if l.key != "" {
+			fm.set(l.key, l.value)
+		}
+	}
 	fm.set("updated_at", time.Now().UTC().Format(time.RFC3339))
 	fm.set("supersedes", priorHash)
 	if opts.Reason != "" {
 		fm.set("supersede_reason", opts.Reason)
 	}
 
-	out := []byte(fm.render() + opts.Content)
+	// Validate the envelope AFTER the merge, against the full field set that
+	// is about to reach disk — not just the caller's fragment. Validating the
+	// fragment alone would miss a caller that supersedes claim_provenance to
+	// empty while half_life/applies survive untouched from the prior note:
+	// each side looks individually fine, but the merged result is an
+	// unprovenanced envelope, which is the exact laundering this check
+	// exists to catch. (Caught in review before merge, not filed after —
+	// worth being honest about in the history: this second pass was the
+	// actual fix; the first one validated the wrong document.)
+	envelope := make(map[string]string, len(fm.lines))
+	for _, l := range fm.lines {
+		if l.key != "" {
+			envelope[l.key] = l.value
+		}
+	}
+	if err := claim.ValidateEnvelope(envelope); err != nil {
+		return "", "", "", fmt.Errorf("claim envelope: %w", err)
+	}
+
+	out := []byte(fm.render() + contentBody)
 	if err := os.WriteFile(abs, out, 0o644); err != nil {
 		return "", "", "", fmt.Errorf("write: %w", err)
 	}

ingestion/internal/api/update_test.go

@@ -52,6 +52,114 @@ func TestUpdateNoteSupersedesAndStamps(t *testing.T) {
 	assert.Contains(t, s, "supersede_reason: facts changed")
 }
 
+func TestUpdateNoteRejectsInvalidEnvelopeAndWritesNothing(t *testing.T) {
+	// hyperguild#111: WriteNote validates the claim envelope before create;
+	// UpdateNote didn't before supersede, so the same rule must hold on
+	// change as on birth, fail-closed, nothing written on rejection.
+	brainDir := t.TempDir()
+	original := "---\nwing: jepa-fx\nhall: facts\ncreated_at: 2026-01-01T00:00:00Z\n---\n# Old\n\nold body\n"
+	rel := seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md", original)
+
+	_, _, _, err := UpdateNote(brainDir, UpdateNoteOptions{
+		Path:    rel,
+		Content: "---\nhalf_life: forever\n---\n# New\n\nnew body\n",
+	})
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "claim envelope")
+
+	got, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(rel)))
+	require.NoError(t, err)
+	assert.Equal(t, original, string(got), "rejected update must leave the note byte-identical")
+}
+
+func TestUpdateNoteRejectsAppliesWithoutProvenance(t *testing.T) {
+	brainDir := t.TempDir()
+	original := "---\nwing: jepa-fx\nhall: facts\n---\nold\n"
+	rel := seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md", original)
+
+	_, _, _, err := UpdateNote(brainDir, UpdateNoteOptions{
+		Path:    rel,
+		Content: "---\napplies: universal\n---\nnew\n",
+	})
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "claim envelope")
+
+	got, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(rel)))
+	require.NoError(t, err)
+	assert.Equal(t, original, string(got))
+}
+
+func TestUpdateNoteAcceptsValidEnvelopeAndMergesIntoFrontmatter(t *testing.T) {
+	brainDir := t.TempDir()
+	rel := seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md",
+		"---\nwing: jepa-fx\nhall: facts\ncreated_at: 2026-01-01T00:00:00Z\n---\nold\n")
+
+	_, _, _, err := UpdateNote(brainDir, UpdateNoteOptions{
+		Path:    rel,
+		Content: "---\nhalf_life: durable\napplies: universal\nclaim_provenance: asserted\n---\nnew body\n",
+	})
+	require.NoError(t, err)
+
+	got, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(rel)))
+	require.NoError(t, err)
+	s := string(got)
+	assert.Contains(t, s, "half_life: durable")
+	assert.Contains(t, s, "applies: universal")
+	assert.Contains(t, s, "claim_provenance: asserted")
+	assert.Contains(t, s, "wing: jepa-fx", "prior fields survive")
+	assert.Contains(t, s, "new body")
+	assert.Equal(t, 2, strings.Count(s, "---\n"),
+		"exactly one open+close fence pair — the caller's own fence must not leak in as a second, inert block")
+}
+
+func TestUpdateNoteRejectsClearingProvenanceWhileEnvelopeSurvives(t *testing.T) {
+	// Found in review, not written speculatively: validating only the
+	// caller's fragment (rather than the merged result) let a caller blank
+	// out claim_provenance alone while half_life/applies survived from the
+	// prior note untouched — each side looks fine on its own, the merged
+	// envelope on disk is the unprovenanced one the whole check exists to
+	// catch.
+	brainDir := t.TempDir()
+	original := "---\nwing: jepa-fx\nhall: facts\nhalf_life: durable\napplies: universal\nclaim_provenance: asserted\n---\nold\n"
+	rel := seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md", original)
+
+	_, _, _, err := UpdateNote(brainDir, UpdateNoteOptions{
+		Path:    rel,
+		Content: "---\nclaim_provenance: \n---\nnew body\n",
+	})
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "claim envelope")
+
+	got, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(rel)))
+	require.NoError(t, err)
+	assert.Equal(t, original, string(got), "rejected update must leave the note byte-identical")
+}
+
+func TestUpdateNoteWithoutEnvelopeFieldsIsUnchangedFromToday(t *testing.T) {
+	// Regression pin: plain fence-less content (the common case) must behave
+	// exactly as it did before the envelope-merge fix.
+	brainDir := t.TempDir()
+	rel := seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md",
+		"---\nwing: jepa-fx\nhall: facts\ncreated_at: 2026-01-01T00:00:00Z\ncustom: keep-me\n---\n# Old\n\nold body\n")
+
+	relPath, hash, priorHash, err := UpdateNote(brainDir, UpdateNoteOptions{
+		Path:    rel,
+		Content: "# New\n\nnew body\n",
+		Reason:  "facts changed",
+	})
+	require.NoError(t, err)
+	assert.Equal(t, rel, relPath)
+	assert.NotEmpty(t, hash)
+	assert.NotEqual(t, hash, priorHash)
+
+	got, err := os.ReadFile(filepath.Join(brainDir, filepath.FromSlash(rel)))
+	require.NoError(t, err)
+	s := string(got)
+	assert.Contains(t, s, "# New")
+	assert.Contains(t, s, "custom: keep-me")
+	assert.Contains(t, s, "supersedes: "+priorHash)
+}
+
 func TestUpdateNoteResolvesByWingHallSlug(t *testing.T) {
 	brainDir := t.TempDir()
 	seedNote(t, brainDir, "wiki/jepa-fx/facts/val-vol.md",

ingestion/internal/mcp/tools_notes.go

@@ -3,6 +3,7 @@ package mcp
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log/slog"
 	"strings"
@@ -180,6 +181,13 @@ func (s *Server) editWithScope(args json.RawMessage, scope notes.Scope) (notes.R
 	}
 	res, err := notes.Edit(s.brainDir, a.Path, a.OldStr, a.NewStr, scope)
 	if err != nil {
+		if errors.Is(err, notes.ErrDegenerate) && a.OldStr == "" {
+			// hyperguild#115: "old_str is empty" alone doesn't say whether the
+			// caller sent it empty or a hop between the caller and here lost
+			// it. Naming the raw argument byte count makes that distinguishable
+			// without a second investigation.
+			return notes.Result{}, nil, fmt.Errorf("%w (raw arguments were %d bytes)", err, len(args))
+		}
 		return notes.Result{}, nil, err
 	}
 

ingestion/internal/mcp/tools_notes_test.go

@@ -70,6 +70,29 @@ func TestBrainReadAndEdit_RoundTripThroughJSONRPC(t *testing.T) {
 		"only the matched bytes may change")
 }
 
+func TestBrainEdit_EmptyOldStrErrorNamesRawArgumentBytes(t *testing.T) {
+	// hyperguild#115: a session reported "old_str is empty" with an old_str
+	// that, on their end, was never empty. The server-side path was
+	// unreachable to reproduce (verified separately: a fresh brain_edit call
+	// with real content round-trips cleanly), which points at something
+	// between a specific client and this call losing the field. The fix this
+	// issue actually asked for isn't a behavior change — old_str=="" must
+	// still refuse — it's that the refusal should say how many raw argument
+	// bytes it received, so "client sent empty" is distinguishable from
+	// "server received empty after some hop lost it" without a second
+	// session's worth of guessing.
+	dir := newBrainRepo(t)
+	srv := mcp.NewServer(dir, nil, nil, nil)
+
+	resp := call(t, srv, "brain_edit", map[string]any{
+		"path": "wiki/homelab/facts/n.md", "old_str": "", "new_str": "BETA",
+	})
+	errMsg, ok := resp["error"].(map[string]any)["message"].(string)
+	require.True(t, ok, "%v", resp)
+	assert.Contains(t, errMsg, "old_str is empty")
+	assert.Contains(t, errMsg, "raw arguments were", "%v", errMsg)
+}
+
 func TestBrainEdit_RefusesGovernanceFilesFromTheModelFacingTool(t *testing.T) {
 	dir := newBrainRepo(t)
 	srv := mcp.NewServer(dir, nil, nil, nil)

ingestion/internal/pipeline/build.go

@@ -76,6 +76,9 @@ func buildFrontmatter(rp RawPage, date string) string {
 		}
 		fmt.Fprintf(&sb, "date_ingested: %s\n", date)
 		fmt.Fprintf(&sb, "last_updated: %s\n", date)
+		if rp.SourceHash != "" {
+			fmt.Fprintf(&sb, "source_hash: %s\n", rp.SourceHash)
+		}
 		if rp.Source != "" {
 			fmt.Fprintf(&sb, "source: %s\n", yamlScalar(rp.Source))
 		}

ingestion/internal/pipeline/parse.go

@@ -20,9 +20,13 @@ type RawPage struct {
 	// ingested content's own frontmatter (see parseContentFrontmatter) — never
 	// set by the LLM. json:"-" keeps them immune to same-named keys the LLM
 	// might emit. Only meaningful for Type == "source".
-	Source    string `json:"-"`
-	Author    string `json:"-"`
-	Published string `json:"-"`
+	// SourceHash is sha256 of the ingested BODY (frontmatter excluded), stamped
+	// so the next ingest of the same source can tell "unchanged" from "edited"
+	// without re-running extraction (#105).
+	SourceHash string `json:"-"`
+	Source     string `json:"-"`
+	Author     string `json:"-"`
+	Published  string `json:"-"`
 }
 
 // ParseRawPages parses LLM output as a JSON array of RawPage objects.
@@ -112,6 +116,11 @@ type sourceMeta struct {
 	Source    string
 	Author    string
 	Published string
+	// BodyHash is sha256 of the content with any leading frontmatter removed.
+	// Body-only on purpose: a re-crawl that stamps a new fetch date has not
+	// changed the source, and treating that as drift would re-extract the
+	// whole corpus every time a crawler ran (#105).
+	BodyHash string
 }
 
 // parseContentFrontmatter extracts source/author/published from a leading
@@ -154,6 +163,7 @@ func applySourceMeta(pages []RawPage, meta sourceMeta) {
 		if pages[i].Type != "source" {
 			continue
 		}
+		pages[i].SourceHash = meta.BodyHash
 		pages[i].Source = meta.Source
 		pages[i].Author = meta.Author
 		pages[i].Published = meta.Published

ingestion/internal/pipeline/pipeline.go

@@ -3,6 +3,8 @@ package pipeline
 
 import (
 	"context"
+	"crypto/sha256"
+	"encoding/hex"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -26,6 +28,11 @@ type Config struct {
 type Result struct {
 	Pages    []string // relative paths written (or would-be written in dry-run)
 	Warnings []string
+	// Skipped reports that the source was byte-identical to the last ingest,
+	// so no extraction ran and nothing was written. Reported rather than
+	// silent: a run that does nothing must say so, or "the pipeline is fine"
+	// and "the pipeline stopped working" look the same (#105, #107).
+	Skipped bool
 }
 
 // Run ingests content and writes structured wiki pages to brainDir/wiki/.
@@ -43,6 +50,18 @@ func Run(ctx context.Context, cfg Config, brainDir, content, source string, dryR
 
 	sourceSlug := wiki.Slug(source)
 	date := time.Now().UTC().Format("2006-01-02")
+
+	// Drift check BEFORE any extraction: an unchanged source costs a full LLM
+	// pass over every chunk to produce a result that merges to nothing (#105).
+	// The merge is already idempotent (#103), so this is cost and signal, not
+	// correctness — which is why it is safe for it to be an early return.
+	bodyHash := hashBody(content)
+	if !dryRun && bodyHash != "" && bodyHash == storedSourceHash(brainDir, sourceSlug) {
+		return Result{Skipped: true, Warnings: []string{
+			fmt.Sprintf("source %q unchanged since last ingest (hash %s) — extraction skipped", source, bodyHash[:12]),
+		}}, nil
+	}
+
 	chunks := Chunk(content, cfg.ChunkSize)
 
 	var allRaw []RawPage
@@ -59,7 +78,9 @@ func Run(ctx context.Context, cfg Config, brainDir, content, source string, dryR
 		allWarnings = append(allWarnings, warnings...)
 	}
 
-	applySourceMeta(allRaw, parseContentFrontmatter(content))
+	meta := parseContentFrontmatter(content)
+	meta.BodyHash = bodyHash
+	applySourceMeta(allRaw, meta)
 
 	return buildAndWrite(allRaw, sourceSlug, date, brainDir, source, inventory, allWarnings, dryRun)
 }
@@ -96,7 +117,11 @@ func buildAndWrite(rawPages []RawPage, sourceSlug, date, brainDir, source string
 			if err := os.MkdirAll(filepath.Dir(dest), 0o755); err != nil {
 				return Result{}, fmt.Errorf("mkdir for %s: %w", page.Path, err)
 			}
-			if err := os.WriteFile(dest, []byte(page.Content), 0o644); err != nil {
+			content, err := reviseOrCreate(dest, page)
+			if err != nil {
+				return Result{}, err
+			}
+			if err := os.WriteFile(dest, []byte(content), 0o644); err != nil {
 				return Result{}, fmt.Errorf("write %s: %w", page.Path, err)
 			}
 		}
@@ -115,6 +140,75 @@ func buildAndWrite(rawPages []RawPage, sourceSlug, date, brainDir, source string
 	return Result{Pages: written, Warnings: warnings}, nil
 }
 
+// hashBody returns sha256 of content with any leading frontmatter block
+// removed, or "" for empty content.
+//
+// Body-only on purpose: a re-crawl that stamps a new fetch date has not changed
+// the source, and treating that as drift would re-extract the corpus every time
+// a crawler ran (#105).
+func hashBody(content string) string {
+	body := content
+	if strings.HasPrefix(body, "---\n") {
+		if _, rest, found := strings.Cut(body[4:], "\n---"); found {
+			body = strings.TrimPrefix(rest, "\n")
+		}
+	}
+	if strings.TrimSpace(body) == "" {
+		return ""
+	}
+	sum := sha256.Sum256([]byte(body))
+	return hex.EncodeToString(sum[:])
+}
+
+// storedSourceHash reads source_hash from the source page a previous ingest
+// wrote, or "" when there is no such page or no such field.
+//
+// Absence always means "extract". That is the fail-safe direction: a missed
+// skip costs one extraction, while a wrong skip loses an update silently — and
+// silence is the failure mode this repo keeps paying for.
+func storedSourceHash(brainDir, sourceSlug string) string {
+	raw, err := os.ReadFile(filepath.Join(brainDir, "wiki", "sources", sourceSlug+".md"))
+	if err != nil {
+		return ""
+	}
+	for _, line := range strings.Split(string(raw), "\n") {
+		if key, value, found := strings.Cut(line, ":"); found && strings.TrimSpace(key) == "source_hash" {
+			return strings.TrimSpace(value)
+		}
+	}
+	return ""
+}
+
+// reviseOrCreate returns the bytes to write for one extracted page: merged into
+// whatever is already on disk, or the page as-is when the path is new.
+//
+// This is the compile half of compile-on-ingest. Before it, the write was an
+// unconditional os.WriteFile, so re-ingesting a source replaced its page
+// wholesale and discarded everything accumulated since — including human edits
+// (hyperguild#43: "re-ingest overwrites wholesale").
+//
+// The merge is deliberately asymmetric in the existing page's favour:
+// wiki.Merge keeps the on-disk frontmatter and the on-disk version of any
+// section both sides carry, adds sections only the extraction produced, and
+// unions bullet lists. So a freshly extracted page can add to a note but never
+// silently rewrite what a human put there — which is what makes it safe to run
+// this on every ingest rather than behind a review gate.
+//
+// Known limitation: because the on-disk frontmatter wins, `last_updated` keeps
+// its first-ingest date on a revised page. Left deliberately — the alternative
+// is this function editing frontmatter it does not own, and no lint reads that
+// field today.
+func reviseOrCreate(dest string, page wiki.Page) (string, error) {
+	existing, err := os.ReadFile(dest)
+	switch {
+	case os.IsNotExist(err):
+		return page.Content, nil
+	case err != nil:
+		return "", fmt.Errorf("read existing %s: %w", page.Path, err)
+	}
+	return wiki.Merge(wiki.Page{Path: page.Path, Content: string(existing)}, page).Content, nil
+}
+
 // mergeAll deduplicates pages by path, merging content from later occurrences.
 func mergeAll(pages []wiki.Page) []wiki.Page {
 	order := make([]string, 0, len(pages))

ingestion/internal/pipeline/pipeline_test.go

@@ -171,3 +171,125 @@ func mustJSON(v any) string {
 	}
 	return string(b)
 }
+
+// --- B1: compile-on-ingest — revise the existing page, never clobber it -----
+
+func TestRunRaw_MergesIntoAnExistingPageInsteadOfOverwritingIt(t *testing.T) {
+	// Before this, buildAndWrite did an unconditional os.WriteFile: re-ingesting
+	// a source replaced its page wholesale, discarding anything accumulated
+	// since — including human edits. hyperguild#43 recorded the symptom as
+	// "re-ingest overwrites wholesale".
+	dir := t.TempDir()
+	page := filepath.Join(dir, "wiki", "sources", "shape-up.md")
+	require.NoError(t, os.MkdirAll(filepath.Dir(page), 0o755))
+	require.NoError(t, os.WriteFile(page, []byte(`---
+title: 'Shape Up'
+---
+
+## Summary
+
+A book about shaping product work.
+
+## My Take
+
+Read this before the next planning cycle.
+`), 0o644))
+
+	_, err := RunRaw(dir, "shape-up", []RawPage{{
+		Title: "Shape Up", Type: "source", Subtype: "book", Domain: "product-strategy",
+		Content: "## Summary\n\nA book about shaping product work.\n\n## Key Claims\n\n- Appetite beats estimation.\n",
+	}}, false)
+	require.NoError(t, err)
+
+	got, err := os.ReadFile(page)
+	require.NoError(t, err)
+	s := string(got)
+
+	assert.Contains(t, s, "## My Take", "a section the extraction never saw must survive the merge")
+	assert.Contains(t, s, "Read this before the next planning cycle.")
+	assert.Contains(t, s, "Appetite beats estimation.", "newly extracted material must still land")
+}
+
+func TestRunRaw_ReIngestingUnchangedContentIsByteIdentical(t *testing.T) {
+	// Compile-on-ingest runs on every ingest, so "nothing changed" must produce
+	// no diff at all. Otherwise every re-ingest dirties the tree, brain-sync
+	// commits it, and the git history fills with noise that hides real edits.
+	dir := t.TempDir()
+	raw := []RawPage{{
+		Title: "Shape Up", Type: "source", Subtype: "book", Domain: "product-strategy",
+		Content: "## Summary\n\nA book about shaping product work.\n\n## Open Questions\n\n- Does appetite scale?\n",
+	}}
+
+	_, err := RunRaw(dir, "shape-up", raw, false)
+	require.NoError(t, err)
+	first, err := os.ReadFile(filepath.Join(dir, "wiki", "sources", "shape-up.md"))
+	require.NoError(t, err)
+
+	_, err = RunRaw(dir, "shape-up", raw, false)
+	require.NoError(t, err)
+	second, err := os.ReadFile(filepath.Join(dir, "wiki", "sources", "shape-up.md"))
+	require.NoError(t, err)
+
+	assert.Equal(t, string(first), string(second),
+		"re-ingesting unchanged content must leave the page byte-identical")
+}
+
+// --- #105: source drift — an unchanged re-ingest must not re-extract --------
+
+func TestRun_SkipsExtractionWhenTheSourceIsUnchanged(t *testing.T) {
+	// #103 made a re-ingest harmless (byte-identical merge). It is still not
+	// free: the full LLM extraction runs over every chunk to produce a result
+	// that merges to nothing. This is the cost half.
+	dir := t.TempDir()
+	var calls int
+	cfg := Config{Complete: func(_ context.Context, _, _ string) (string, error) {
+		calls++
+		return `[{"title":"Shape Up","type":"source","subtype":"book","domain":"product","content":"## Summary\n\nA book.\n"}]`, nil
+	}}
+
+	content := "---\nsource: https://example.com/shape-up\n---\n\nThe body of the article.\n"
+
+	first, err := Run(context.Background(), cfg, dir, content, "shape-up", false)
+	require.NoError(t, err)
+	require.Equal(t, 1, calls, "first ingest must extract")
+	assert.False(t, first.Skipped)
+
+	second, err := Run(context.Background(), cfg, dir, content, "shape-up", false)
+	require.NoError(t, err)
+	assert.Equal(t, 1, calls, "unchanged content must not be extracted again")
+	assert.True(t, second.Skipped, "the skip must be reported, not silent")
+}
+
+func TestRun_ReExtractsWhenTheSourceBodyChanged(t *testing.T) {
+	dir := t.TempDir()
+	var calls int
+	cfg := Config{Complete: func(_ context.Context, _, _ string) (string, error) {
+		calls++
+		return `[{"title":"Shape Up","type":"source","subtype":"book","domain":"product","content":"## Summary\n\nA book.\n"}]`, nil
+	}}
+
+	_, err := Run(context.Background(), cfg, dir, "---\nsource: x\n---\n\nversion one\n", "shape-up", false)
+	require.NoError(t, err)
+	_, err = Run(context.Background(), cfg, dir, "---\nsource: x\n---\n\nversion two — the source was edited\n", "shape-up", false)
+	require.NoError(t, err)
+
+	assert.Equal(t, 2, calls, "changed content must be re-extracted")
+}
+
+func TestRun_FrontmatterOnlyChangeIsNotDrift(t *testing.T) {
+	// The hash covers the body, so re-fetching a page whose metadata moved
+	// (a re-crawl stamping a new date) is not treated as the source changing.
+	dir := t.TempDir()
+	var calls int
+	cfg := Config{Complete: func(_ context.Context, _, _ string) (string, error) {
+		calls++
+		return `[{"title":"Shape Up","type":"source","subtype":"book","domain":"product","content":"## Summary\n\nA book.\n"}]`, nil
+	}}
+
+	_, err := Run(context.Background(), cfg, dir, "---\nsource: x\nfetched: monday\n---\n\nsame body\n", "shape-up", false)
+	require.NoError(t, err)
+	_, err = Run(context.Background(), cfg, dir, "---\nsource: x\nfetched: tuesday\n---\n\nsame body\n", "shape-up", false)
+	require.NoError(t, err)
+
+	assert.Equal(t, 1, calls, "only the body counts as the source")
+}

ingestion/internal/wiki/merge.go

@@ -3,6 +3,7 @@ package wiki
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 )
 
@@ -29,12 +30,16 @@ type section struct {
 }
 
 // Merge combines two Page values with the same path.
-// Frontmatter is taken from a. Sections are merged by strategy:
-// bullet sections union unique lines, append sections concatenate,
-// all others keep a's version. Sections in b not present in a are appended.
+// Frontmatter is taken from a. The preamble (content before the first ##
+// heading) is taken from a — same "on-disk wins" default every unlisted
+// named section gets, kept as a separate field rather than a section with
+// an empty heading so it can never collide with one (see parseSections).
+// Sections are merged by strategy: bullet sections union unique lines,
+// append sections concatenate, all others keep a's version. Sections in b
+// not present in a are appended.
 func Merge(a, b Page) Page {
-	fmA, secsA := parseSections(a.Content)
-	_, secsB := parseSections(b.Content)
+	fmA, preambleA, secsA := parseSections(a.Content)
+	fmB, _, secsB := parseSections(b.Content)
 
 	idx := make(map[string]int, len(secsA))
 	for i, s := range secsA {
@@ -53,14 +58,168 @@ func Merge(a, b Page) Page {
 		case bulletSections[sB.heading]:
 			secsA[i].content = mergeBullets(sA.content, sB.content)
 		case appendSections[sB.heading]:
-			secsA[i].content = strings.TrimRight(sA.content, "\n") + "\n\n" + strings.TrimLeft(sB.content, "\n")
+			secsA[i].content = appendNew(sA.content, sB.content)
 		}
 	}
 
-	return Page{Path: a.Path, Content: rebuildContent(fmA, secsA)}
+	return Page{Path: a.Path, Content: rebuildContent(refreshOwned(fmA, fmB), preambleA, secsA)}
 }
 
-func parseSections(markdown string) (frontmatter string, sections []section) {
+// generatorOwned names the frontmatter fields the ingest pipeline may refresh
+// on a page it is revising. Everything else on disk wins.
+//
+// #103 made the on-disk frontmatter win wholesale, which is what stops a
+// regenerating writer from overwriting human-set metadata — a title someone
+// fixed, or the claim-property envelope (brain#21). The cost was that fields
+// the generator legitimately owns froze at their first-ingest values: when it
+// last ran, and what it last saw.
+//
+// An explicit allowlist rather than a carve-out: the ownership boundary is
+// nameable, and a field nobody has thought about stays human-owned by default,
+// which is the safe direction.
+var generatorOwned = map[string]bool{
+	"last_updated": true,
+	"source_hash":  true,
+}
+
+// fmLine is one line of a frontmatter block: a parsed key/value pair, or a
+// raw line (blank, comment, or anything else that isn't a simple "key:
+// value") kept verbatim. Same shape as api.frontmatter's fmLine — this
+// package doesn't import that one (it's unexported there, and a's/b's
+// frontmatter here always arrives as a string, not a parsed struct), so the
+// small, already-proven set()-appends-if-absent behavior is reproduced
+// locally rather than string-index surgery reinvented per call site.
+type fmLine struct {
+	key, value, raw string
+}
+
+// parseFrontmatterBlock parses a "---\n...\n---\n" fenced block (the shape
+// parseSections produces) into an ordered line list. A block with no
+// opening/closing fence — including the empty string, a page with no
+// frontmatter at all — returns nil, ok=false: there is nothing to update in
+// place, only something to potentially create.
+func parseFrontmatterBlock(block string) (lines []fmLine, ok bool) {
+	if !strings.HasPrefix(block, "---\n") {
+		return nil, false
+	}
+	rest := block[len("---\n"):]
+	end := strings.Index(rest, "\n---\n")
+	if end < 0 {
+		return nil, false
+	}
+	for _, line := range strings.Split(rest[:end], "\n") {
+		// An indented line is a continuation (a YAML block-list item, a
+		// wrapped value) never a top-level key, regardless of whether it
+		// happens to contain a colon — "  - 'Chapter 3: The Reckoning'"
+		// is not a key named "- 'Chapter 3". Checked before Cut so a
+		// colon inside one never reaches the key/value path at all.
+		if line != "" && (line[0] == ' ' || line[0] == '\t') {
+			lines = append(lines, fmLine{raw: line})
+			continue
+		}
+		key, val, found := strings.Cut(line, ":")
+		key = strings.TrimSpace(key)
+		if !found || key == "" || strings.HasPrefix(strings.TrimSpace(line), "#") {
+			lines = append(lines, fmLine{raw: line})
+			continue
+		}
+		lines = append(lines, fmLine{key: key, value: strings.TrimSpace(val)})
+	}
+	return lines, true
+}
+
+// setLine updates key's value in place if lines already has it, or appends
+// a new entry if it doesn't — the one behavior the original refreshOwned
+// got wrong (PR #126 review, round 2: it only ever updated in place).
+func setLine(lines []fmLine, key, value string) []fmLine {
+	for i := range lines {
+		if lines[i].key == key {
+			lines[i].value = value
+			return lines
+		}
+	}
+	return append(lines, fmLine{key: key, value: value})
+}
+
+func renderFrontmatterBlock(lines []fmLine) string {
+	if len(lines) == 0 {
+		return ""
+	}
+	var sb strings.Builder
+	sb.WriteString("---\n")
+	for _, l := range lines {
+		switch {
+		case l.key == "":
+			sb.WriteString(l.raw)
+		case l.value == "":
+			// A key with nothing after the colon (the YAML block-list shape:
+			// "aliases:" followed by indented "- item" lines on their own
+			// raw lines) must stay bare — "key: " with a trailing space
+			// is a different, if invisible, byte sequence, and this file's
+			// whole purpose is byte-stability across an unrelated merge.
+			sb.WriteString(l.key)
+			sb.WriteByte(':')
+		default:
+			sb.WriteString(l.key)
+			sb.WriteString(": ")
+			sb.WriteString(l.value)
+		}
+		sb.WriteByte('\n')
+	}
+	sb.WriteString("---\n")
+	return sb.String()
+}
+
+// refreshOwned returns a's frontmatter with the generator-owned fields taken
+// from b where b supplies them. Fields absent from b keep a's value, so a
+// generator that stops emitting a field cannot blank it.
+//
+// A field b supplies that a doesn't have yet — every page ingested before
+// this mechanism existed has no source_hash line at all — is appended, not
+// dropped (round 1 of review: dropping it silently meant source_hash never
+// populated for the pre-existing corpus). If a has no frontmatter fence at
+// all, one is created to hold the new fields rather than splicing raw
+// "key: value" text into the body (round 2: that corrupted the page and the
+// fields would duplicate on every subsequent merge, since unfenced text
+// isn't recognized as frontmatter by parseSections on the next pass).
+func refreshOwned(a, b string) string {
+	bLines, _ := parseFrontmatterBlock(b)
+	bVals := make(map[string]string)
+	for _, l := range bLines {
+		if l.key != "" && generatorOwned[l.key] {
+			bVals[l.key] = l.value
+		}
+	}
+	if len(bVals) == 0 {
+		return a
+	}
+
+	aLines, _ := parseFrontmatterBlock(a) // ok==false (no fence) -> aLines nil, same as "start fresh"
+
+	// Sorted for a deterministic, byte-stable result when more than one
+	// field is appended in the same call — map iteration order isn't.
+	keys := make([]string, 0, len(bVals))
+	for k := range bVals {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		aLines = setLine(aLines, k, bVals[k])
+	}
+	return renderFrontmatterBlock(aLines)
+}
+
+// parseSections splits markdown into its frontmatter, its preamble (content
+// before the first `## ` heading), and its `## `-headed sections.
+//
+// The preamble is returned separately rather than as a section with an
+// empty heading — a section keyed by heading=="" would collide with a
+// literal degenerate `## ` (marker, no title text; strings.TrimPrefix also
+// yields ""), which is a distinct, addressable section a page can genuinely
+// have, not the same thing as "no heading yet." Two entries sharing one key
+// in Merge's idx map means one of them silently loses lookup visibility —
+// found in review as real, reproducible data loss, not a hypothetical.
+func parseSections(markdown string) (frontmatter, preamble string, sections []section) {
 	lines := strings.Split(markdown, "\n")
 	i := 0
 
@@ -78,6 +237,22 @@ func parseSections(markdown string) (frontmatter string, sections []section) {
 		frontmatter = fmt.Sprintf("---\n%s\n---\n", strings.Join(fmLines, "\n"))
 	}
 
+	// Everything before the first `## ` heading — an intro paragraph, or, if
+	// the page has no headings at all, the entire body — is ordinary content,
+	// not something this parser is entitled to drop (hyperguild#103 review:
+	// dropping it meant Merge, one caller up, would silently replace the
+	// whole on-disk body with the fresh extraction whenever a page didn't
+	// follow the ## convention — exactly the class of bug this file exists
+	// to prevent).
+	var preambleLines []string
+	for ; i < len(lines); i++ {
+		if strings.HasPrefix(lines[i], "## ") {
+			break
+		}
+		preambleLines = append(preambleLines, lines[i])
+	}
+	preamble = strings.Join(preambleLines, "\n")
+
 	var cur *section
 	for ; i < len(lines); i++ {
 		line := lines[i]
@@ -96,24 +271,85 @@ func parseSections(markdown string) (frontmatter string, sections []section) {
 	return
 }
 
-func rebuildContent(frontmatter string, sections []section) string {
+// rebuildContent serialises sections back into a page.
+//
+// Each section body is normalised to exactly one trailing newline and no
+// leading blank line. Without that, a section keeps whatever blank lines it was
+// parsed with and this function adds its own, so every merge pass grows the page
+// by a blank line — invisible in a diff viewer, fatal to byte-stability. Compile-on-ingest
+// merges on every run, so "merging changes nothing when nothing changed" has to
+// hold at the byte level, not just the content level.
+func rebuildContent(frontmatter, preamble string, sections []section) string {
 	var sb strings.Builder
 	sb.WriteString(frontmatter)
+	if body := strings.Trim(preamble, "\n"); body != "" {
+		fmt.Fprintf(&sb, "\n%s\n", body)
+	}
 	for _, sec := range sections {
-		fmt.Fprintf(&sb, "\n## %s\n\n%s", sec.heading, sec.content)
+		body := strings.Trim(sec.content, "\n")
+		fmt.Fprintf(&sb, "\n## %s\n\n%s\n", sec.heading, body)
 	}
 	return sb.String()
 }
 
+// canonicalLine collapses a line to its comparison key: internal whitespace
+// runs (a re-extraction's bullet spacing, tabs vs spaces, trailing spaces)
+// must not make the same logical line look new. strings.Fields already
+// trims and splits on any whitespace run, so joining it back with single
+// spaces is exactly "same words, same order, whitespace-insensitive."
+func canonicalLine(line string) string {
+	return strings.Join(strings.Fields(line), " ")
+}
+
+// appendNew concatenates the lines of b that a does not already carry.
+//
+// Append sections used to concatenate wholesale, which is correct exactly once.
+// Compile-on-ingest merges a freshly extracted page into the one already on
+// disk, so an unchanged source re-ingested would grow "Open Questions" and
+// "Updates" on every run until the page is unreadable — and the drift guard
+// that would otherwise catch it (hashing the source body) does not exist yet,
+// so idempotency has to hold here rather than upstream.
+//
+// Line-level rather than block-level: the common case is a re-ingest carrying
+// one genuinely new line alongside several it already has. A block-level
+// "skip if identical" would duplicate the old lines every time that happened.
+//
+// The cost is that a line repeated verbatim on purpose collapses to one. For
+// these sections — questions, updates, evolving notes — a repeat is noise
+// rather than signal, and the failure is conservative: the page stops growing
+// instead of growing wrongly.
+func appendNew(a, b string) string {
+	seen := make(map[string]bool)
+	for _, line := range strings.Split(a, "\n") {
+		if c := canonicalLine(line); c != "" {
+			seen[c] = true
+		}
+	}
+
+	var add []string
+	for _, line := range strings.Split(b, "\n") {
+		c := canonicalLine(line)
+		if c == "" || seen[c] {
+			continue
+		}
+		seen[c] = true
+		add = append(add, line)
+	}
+	if len(add) == 0 {
+		return a // nothing new — leave the section byte-identical
+	}
+	return strings.TrimRight(a, "\n") + "\n\n" + strings.Join(add, "\n") + "\n"
+}
+
 func mergeBullets(a, b string) string {
 	seen := make(map[string]bool)
 	var lines []string
 	for _, line := range strings.Split(a+b, "\n") {
-		trimmed := strings.TrimSpace(line)
-		if trimmed == "" || seen[trimmed] {
+		c := canonicalLine(line)
+		if c == "" || seen[c] {
 			continue
 		}
-		seen[trimmed] = true
+		seen[c] = true
 		lines = append(lines, line)
 	}
 	return strings.Join(lines, "\n") + "\n"

ingestion/internal/wiki/merge_test.go

@@ -53,3 +53,282 @@ func TestMerge_KeepsFrontmatterFromA(t *testing.T) {
 	assert.Contains(t, got.Content, "title: A")
 	assert.NotContains(t, got.Content, "title: B")
 }
+
+// --- hyperguild#103 review: a page with content outside any `## ` section ---
+// must never lose that content on merge. parseSections used to only capture
+// text between `## ` headings — anything before the first heading (a common,
+// ordinary shape for a hand-written note: an intro paragraph before the first
+// section) or, worse, an entire page with no `## ` headings at all (a legacy
+// note, a stub, any hand-edit that doesn't follow the section convention)
+// vanished silently. Merge would then fill the page entirely from the fresh
+// extraction — the opposite of "never silently rewrite what a human put
+// there," the guarantee this whole file exists to provide.
+
+func TestMerge_PreservesOnDiskContentWithNoSectionHeadings(t *testing.T) {
+	a := Page{Path: "wiki/x.md", Content: "---\ntitle: X\n---\n\nJust some free text a human wrote. No section headings at all.\n"}
+	b := Page{Path: "wiki/x.md", Content: "---\ntitle: X\n---\n\n## Definition\n\nFresh extraction's take.\n"}
+
+	got := Merge(a, b)
+	assert.Contains(t, got.Content, "Just some free text a human wrote",
+		"on-disk content with no ## headings must survive the merge, not be replaced wholesale by the fresh extraction")
+}
+
+func TestMerge_DegenerateEmptyHeadingDoesNotCollideWithPreamble(t *testing.T) {
+	// Second review pass on #103: representing the preamble as a section with
+	// heading=="" collides with a literal `## ` (marker, no title text) —
+	// strings.TrimPrefix("## ", "## ") is also "". `a` has only a preamble
+	// (no degenerate heading of its own); `b` introduces a genuinely new
+	// degenerate `## ` section. Because both key to "", Merge's idx thinks
+	// b's section "already exists" in a (it's really just a's unrelated
+	// preamble) and never adds it — b's section vanishes from the output
+	// entirely, not merged, not kept, not appended.
+	a := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\nAn intro paragraph.\n\n## Definition\n\nA thing.\n"}
+	b := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\n## \n\nA genuinely new degenerate section's body.\n\n## Definition\n\nA thing.\n"}
+
+	got := Merge(a, b)
+	assert.Contains(t, got.Content, "An intro paragraph.", "a's own preamble must survive")
+	assert.Contains(t, got.Content, "A genuinely new degenerate section's body.",
+		"b's degenerate section is new content, not a collision with a's unrelated preamble — it must not be silently dropped")
+}
+
+func TestMerge_PreservesPreambleBeforeFirstHeading(t *testing.T) {
+	a := Page{Path: "wiki/x.md", Content: "---\ntitle: X\n---\n\nAn intro paragraph before the first heading.\n\n## Definition\n\nA thing.\n"}
+	b := Page{Path: "wiki/x.md", Content: "---\ntitle: X\n---\n\n## Definition\n\nA thing.\n"}
+
+	got := Merge(a, b)
+	assert.Contains(t, got.Content, "An intro paragraph before the first heading",
+		"text before the first ## heading is ordinary page content, not something the parser is entitled to drop")
+}
+
+// --- hyperguild#103 review: dedup must be whitespace-insensitive -----------
+// Page content is produced by an LLM per run, so byte-identical re-extraction
+// of "the same" logical line is not guaranteed — different bullet spacing or
+// trailing whitespace on an otherwise-identical line must still dedup, or
+// idempotency only holds when the extractor happens to reproduce whitespace
+// exactly, which is not a real guarantee.
+
+func TestMerge_AppendSectionDedupsAcrossWhitespaceVariants(t *testing.T) {
+	a := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\n## Open Questions\n\n- Does this converge?\n"}
+	b := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\n## Open Questions\n\n-   Does this converge?  \n"}
+
+	got := Merge(a, b)
+	assert.Equal(t, 1, strings.Count(got.Content, "Does this converge?"),
+		"same logical line with different whitespace must dedup, not duplicate")
+}
+
+func TestMerge_BulletSectionDedupsAcrossWhitespaceVariants(t *testing.T) {
+	a := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\n## Related Concepts\n\n- [[bar|Bar]]\n"}
+	b := Page{Path: "p.md", Content: "---\ntitle: X\n---\n\n## Related Concepts\n\n-  [[bar|Bar]]\n"}
+
+	got := Merge(a, b)
+	assert.Equal(t, 1, strings.Count(got.Content, "[[bar|Bar]]"),
+		"same logical bullet with different whitespace must dedup, not duplicate")
+}
+
+// --- brain#21/B1: merging must be safe to run again -------------------------
+
+func TestMerge_AppendSectionDoesNotDuplicateContentAlreadyPresent(t *testing.T) {
+	// Compile-on-ingest merges a freshly extracted page into the one already
+	// on disk. Bullet sections union, so they are naturally idempotent — but
+	// append sections concatenate, so re-ingesting an unchanged source would
+	// grow "Open Questions" on every run until the page is unreadable.
+	page := Page{Path: "wiki/sources/x.md", Content: `---
+title: X
+---
+
+## Open Questions
+
+- Does this converge?
+`}
+
+	once := Merge(page, page)
+	twice := Merge(once, page)
+
+	assert.Equal(t, 1, strings.Count(once.Content, "Does this converge?"),
+		"merging a page with itself must not duplicate an append section")
+	assert.Equal(t, once.Content, twice.Content,
+		"merge must be idempotent — a third pass may not keep growing the page")
+}
+
+func TestMerge_AppendSectionStillAccumulatesGenuinelyNewContent(t *testing.T) {
+	// The dedup must not turn append sections into keep-a-only sections:
+	// new material is exactly what compile-on-ingest exists to add.
+	existing := Page{Path: "wiki/sources/x.md", Content: `---
+title: X
+---
+
+## Open Questions
+
+- Does this converge?
+`}
+	fresh := Page{Path: "wiki/sources/x.md", Content: `---
+title: X
+---
+
+## Open Questions
+
+- What happens under load?
+`}
+
+	got := Merge(existing, fresh).Content
+	assert.Contains(t, got, "Does this converge?", "existing question must survive")
+	assert.Contains(t, got, "What happens under load?", "new question must be added")
+}
+
+func TestMerge_GeneratorOwnedFrontmatterFieldsAreRefreshed(t *testing.T) {
+	// #103 made on-disk frontmatter win wholesale, which is what protects
+	// human-set fields from a regenerating writer. The cost was that fields the
+	// generator legitimately owns — when it last ran, what it last saw — froze
+	// at their first-ingest values. An explicit owned-set is the boundary:
+	// named fields the generator may refresh, everything else human-owned.
+	existing := Page{Path: "wiki/sources/x.md", Content: `---
+title: 'X'
+last_updated: 2026-01-01
+source_hash: aaaa
+half_life: durable
+claim_provenance: asserted
+---
+
+## Summary
+
+Original.
+`}
+	fresh := Page{Path: "wiki/sources/x.md", Content: `---
+title: 'Renamed by the model'
+last_updated: 2026-08-22
+source_hash: bbbb
+---
+
+## Summary
+
+Rewritten by the model.
+`}
+
+	got := Merge(existing, fresh).Content
+
+	assert.Contains(t, got, "last_updated: 2026-08-22", "generator owns last_updated")
+	assert.Contains(t, got, "source_hash: bbbb", "generator owns source_hash")
+	assert.Contains(t, got, "title: 'X'", "a human-set title must survive regeneration")
+	assert.Contains(t, got, "half_life: durable", "the claim envelope must survive regeneration")
+	assert.Contains(t, got, "claim_provenance: asserted")
+	assert.Contains(t, got, "Original.", "an existing section still wins over the model's rewrite")
+	assert.NotContains(t, got, "Renamed by the model")
+}
+
+func TestMerge_GeneratorOwnedFieldsAreAppendedWhenAPageNeverHadThemBefore(t *testing.T) {
+	// Found in review of PR #126: refreshOwned only replaced a generator-owned
+	// line that already existed in a's frontmatter — it never appended one a
+	// didn't have. Every page ingested before this feature shipped has no
+	// source_hash line at all, so on its first re-ingest after deploy, the
+	// fresh hash was silently dropped and the skip-on-unchanged feature this
+	// PR exists to build would never engage for the entire pre-existing
+	// corpus, permanently, with nothing telling anyone.
+	existing := Page{Path: "wiki/sources/x.md", Content: `---
+title: 'X'
+---
+
+## Summary
+
+Original.
+`}
+	fresh := Page{Path: "wiki/sources/x.md", Content: `---
+title: 'Renamed by the model'
+last_updated: 2026-08-22
+source_hash: bbbb
+---
+
+## Summary
+
+Rewritten by the model.
+`}
+
+	got := Merge(existing, fresh).Content
+
+	// Exact frontmatter block, not Contains: the second review round found
+	// that a substring check doesn't prove the fields landed inside a valid
+	// fence, in the right order, or that the fence itself wasn't corrupted —
+	// two independent mutations (closeIdx targeting the wrong fence, reversed
+	// sort) both survived a Contains-only version of this test.
+	want := "---\ntitle: 'X'\nlast_updated: 2026-08-22\nsource_hash: bbbb\n---\n\n## Summary\n\nOriginal.\n"
+	assert.Equal(t, want, got)
+}
+
+func TestMerge_GeneratorOwnedFieldsCreateAFrontmatterBlockWhenThePageHadNoneAtAll(t *testing.T) {
+	// Second review round on PR #126: when a has no frontmatter fence at all,
+	// the append fallback spliced raw, unfenced "key: value" lines straight
+	// into the body -- worse than the original bug, because the next
+	// parseSections call wouldn't recognize them as frontmatter (they don't
+	// start with `---`), so they'd be absorbed as ordinary preamble text and
+	// re-duplicate on every subsequent merge instead of updating in place.
+	existing := Page{Path: "wiki/sources/x.md", Content: "## Summary\n\nOriginal.\n"}
+	fresh := Page{Path: "wiki/sources/x.md", Content: `---
+last_updated: 2026-08-22
+source_hash: bbbb
+---
+
+## Summary
+
+Rewritten by the model.
+`}
+
+	got := Merge(existing, fresh).Content
+
+	want := "---\nlast_updated: 2026-08-22\nsource_hash: bbbb\n---\n\n## Summary\n\nOriginal.\n"
+	assert.Equal(t, want, got)
+}
+
+func TestMerge_GeneratorOwnedFieldsMixedReplaceAndAppend(t *testing.T) {
+	// a already has last_updated (replace in place) but not source_hash
+	// (append) -- the two code paths in the same call, together.
+	existing := Page{Path: "wiki/sources/x.md", Content: `---
+title: 'X'
+last_updated: 2026-01-01
+---
+
+## Summary
+
+Original.
+`}
+	fresh := Page{Path: "wiki/sources/x.md", Content: `---
+last_updated: 2026-08-22
+source_hash: bbbb
+---
+
+## Summary
+
+Rewritten by the model.
+`}
+
+	got := Merge(existing, fresh).Content
+
+	want := "---\ntitle: 'X'\nlast_updated: 2026-08-22\nsource_hash: bbbb\n---\n\n## Summary\n\nOriginal.\n"
+	assert.Equal(t, want, got)
+}
+
+func TestRefreshOwned_CommentLinesSurviveUnmangled(t *testing.T) {
+	// Third review round on PR #126: parseFrontmatterBlock dropped the
+	// sibling api package's comment guard (strings.HasPrefix(trimmed, "#")).
+	// Without it, a comment line containing a colon gets cut at the colon
+	// and re-rendered with collapsed whitespace instead of surviving
+	// verbatim.
+	a := "---\n#see also:   https://x/y\ntitle: 'X'\n---\n"
+	b := "---\nsource_hash: bbbb\n---\n"
+
+	got := refreshOwned(a, b)
+	assert.Equal(t, "---\n#see also:   https://x/y\ntitle: 'X'\nsource_hash: bbbb\n---\n", got)
+}
+
+func TestRefreshOwned_IndentedListItemsWithColonsAreNotMisparsedAsKeys(t *testing.T) {
+	// Same round: an indented YAML block-list item that happens to contain a
+	// colon (e.g. a title with a subtitle) is a continuation line, never a
+	// top-level key, regardless of what strings.Cut finds in it. Misparsing
+	// it as a key/value pair and re-rendering strips its indentation,
+	// de-indenting it out of the list it belongs to -- and refreshOwned
+	// re-renders this block on essentially every non-skipped ingest, so this
+	// is the normal path, not an edge case.
+	a := "---\naliases:\n  - 'Chapter 3: The Reckoning'\ntitle: 'X'\n---\n"
+	b := "---\nsource_hash: bbbb\n---\n"
+
+	got := refreshOwned(a, b)
+	assert.Equal(t, "---\naliases:\n  - 'Chapter 3: The Reckoning'\ntitle: 'X'\nsource_hash: bbbb\n---\n", got)
+}

internal/config/config.go

@@ -7,7 +7,6 @@ type Config struct {
 	LiteLLMBaseURL string // LITELLM_BASE_URL, default http://iguana:4000
 	LiteLLMAPIKey  string // LITELLM_API_KEY
 	ConfigDir      string // SUPERVISOR_CONFIG_DIR, default ./config/supervisor
-	ModelsFile     string // SUPERVISOR_MODELS_FILE, default <ConfigDir>/../models.yaml
 	IngestBaseURL  string // INGEST_BASE_URL, default http://localhost:3300
 	IngestSvcURL   string // INGEST_SVC_URL — base URL for brain_ingest (/ingest, /ingest-path)
 	KBRetrievalURL string // KB_RETRIEVAL_URL — base URL for brain_search
@@ -23,7 +22,6 @@ func Load() (Config, error) {
 		LiteLLMAPIKey:  os.Getenv("LITELLM_API_KEY"),
 		ConfigDir:      envOr("SUPERVISOR_CONFIG_DIR", "./config/supervisor"),
 	}
-	cfg.ModelsFile = envOr("SUPERVISOR_MODELS_FILE", cfg.ConfigDir+"/../models.yaml")
 	cfg.IngestBaseURL = envOr("INGEST_BASE_URL", "http://localhost:3300")
 	cfg.IngestSvcURL = envOr("INGEST_SVC_URL", "")
 	cfg.KBRetrievalURL = envOr("KB_RETRIEVAL_URL", "")

internal/config/models.go

@@ -1,49 +0,0 @@
-package config
-
-import (
-	"fmt"
-	"os"
-
-	"gopkg.in/yaml.v3"
-)
-
-type skillChain struct {
-	Chain []string `yaml:"chain"`
-}
-
-type modelsFile struct {
-	DefaultChain []string              `yaml:"default_chain"`
-	Skills       map[string]skillChain `yaml:"skills"`
-}
-
-type Models struct {
-	data modelsFile
-}
-
-func LoadModels(path string) (Models, error) {
-	raw, err := os.ReadFile(path)
-	if err != nil {
-		return Models{}, fmt.Errorf("load models: %w", err)
-	}
-	var f modelsFile
-	if err := yaml.Unmarshal(raw, &f); err != nil {
-		return Models{}, fmt.Errorf("parse models: %w", err)
-	}
-	return Models{data: f}, nil
-}
-
-// ModelFor returns the primary model to use for a skill.
-// If override is non-empty, it is returned directly.
-// Falls back to default_chain[0] when the skill has no explicit entry.
-func (m Models) ModelFor(skill, override string) string {
-	if override != "" {
-		return override
-	}
-	if sc, ok := m.data.Skills[skill]; ok && len(sc.Chain) > 0 {
-		return sc.Chain[0]
-	}
-	if len(m.data.DefaultChain) > 0 {
-		return m.data.DefaultChain[0]
-	}
-	return ""
-}

internal/config/models_test.go

@@ -1,53 +0,0 @@
-package config_test
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-
-	"git.d-ma.be/mathias/hyperguild/internal/config"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-const testYAML = `
-default_chain:
-  - ollama/qwen3-coder-30b-tuned
-  - claude-sonnet-4-6
-
-skills:
-  review:
-    chain:
-      - ollama/devstral-tuned
-      - ollama/gemma4
-      - claude-sonnet-4-6
-  spec:
-    chain:
-      - ollama/phi4
-      - claude-opus-4-6
-`
-
-func writeModels(t *testing.T, content string) string {
-	t.Helper()
-	f := filepath.Join(t.TempDir(), "models.yaml")
-	require.NoError(t, os.WriteFile(f, []byte(content), 0o644))
-	return f
-}
-
-func TestModelsModelForSkillWithEntry(t *testing.T) {
-	m, err := config.LoadModels(writeModels(t, testYAML))
-	require.NoError(t, err)
-	assert.Equal(t, "ollama/devstral-tuned", m.ModelFor("review", ""))
-}
-
-func TestModelsModelForDefaultFallback(t *testing.T) {
-	m, err := config.LoadModels(writeModels(t, testYAML))
-	require.NoError(t, err)
-	assert.Equal(t, "ollama/qwen3-coder-30b-tuned", m.ModelFor("trainer", ""))
-}
-
-func TestModelsModelForCallerOverride(t *testing.T) {
-	m, err := config.LoadModels(writeModels(t, testYAML))
-	require.NoError(t, err)
-	assert.Equal(t, "claude-opus-4-6", m.ModelFor("review", "claude-opus-4-6"))
-}

scripts/smoke-routing.sh

@@ -1,64 +0,0 @@
-#!/usr/bin/env bash
-set -euo pipefail
-
-# Boot the routing binary and exercise its four tools against live deps.
-# Skipped when LITELLM_BASE_URL or BRAIN_URL is unreachable.
-
-LITELLM_BASE_URL="${LITELLM_BASE_URL:-https://llm-api.d-ma.be}"
-BRAIN_URL="${BRAIN_URL:-http://koala:30330}"
-
-if ! curl -sS --max-time 2 "${LITELLM_BASE_URL}/v1/models" >/dev/null 2>&1; then
-  echo "SKIP: LITELLM at ${LITELLM_BASE_URL} unreachable"
-  exit 0
-fi
-if ! curl -sS --max-time 2 "${BRAIN_URL}/query" -X POST -d '{"query":"x","k":1}' -H 'Content-Type: application/json' >/dev/null 2>&1; then
-  echo "SKIP: BRAIN at ${BRAIN_URL} unreachable"
-  exit 0
-fi
-
-PORT=33310
-BIN=$(mktemp)
-trap 'rm -f $BIN; pkill -P $$ -f "$BIN" 2>/dev/null || true' EXIT
-
-go build -o "$BIN" ./cmd/routing
-
-LITELLM_BASE_URL="$LITELLM_BASE_URL" BRAIN_URL="$BRAIN_URL" \
-  ROUTING_PORT="$PORT" SUPERVISOR_CONFIG_DIR="$(pwd)/config/supervisor" \
-  "$BIN" &
-
-# Wait for the binary to bind.
-for _ in $(seq 1 50); do
-  curl -sS "http://127.0.0.1:${PORT}/healthz" >/dev/null 2>&1 && break
-  sleep 0.1
-done
-
-call_tool() {
-  local tool="$1"
-  local args="$2"
-  curl -sS -X POST "http://127.0.0.1:${PORT}/mcp" \
-    -H 'Content-Type: application/json' \
-    -d "{\"jsonrpc\":\"2.0\",\"id\":1,\"method\":\"tools/call\",\"params\":{\"name\":\"${tool}\",\"arguments\":${args}}}" \
-    | jq -e '.result // .error' > /dev/null
-}
-
-echo "calling tools/list..."
-curl -sS -X POST "http://127.0.0.1:${PORT}/mcp" \
-  -H 'Content-Type: application/json' \
-  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' \
-  | jq -r '.result.tools | map(.name) | sort | .[]'
-
-echo "calling each tool..."
-call_tool review          '{"project_root":"/tmp","files":["README.md"],"session_id":"smoke-1"}'
-call_tool debug           '{"project_root":"/tmp","error":"smoke test","session_id":"smoke-1"}'
-call_tool retrospective   '{"session_id":"smoke-1"}'
-call_tool trainer         '{"session_id":"smoke-1"}'
-
-echo "checking brain has _routing entries..."
-sleep 2
-COUNT=$(curl -sS "${BRAIN_URL}/pass-rate?skill=_routing&window=1h" | jq -r '.total // 0')
-if [ "${COUNT}" -lt 4 ]; then
-  echo "FAIL: expected >=4 _routing entries in last 1h, got ${COUNT}"
-  exit 1
-fi
-
-echo "PASS: smoke:routing"

skills/close-session/SKILL.md

@@ -49,12 +49,13 @@ Persist the session via a **single `capture` call** (the `brain:capture` MCP too
 **Assemble one payload:**
 
 - **`insights[]`** — the generalizable learnings from Phase 1 (decisions/failures worth re-reading). Each: `{text, wing, hall}`; add `supersede_slug` to revise a prior note in place instead of creating a duplicate. `hall` ∈ facts/decisions/failures/hypotheses/sources.
+  Optional claim envelope, per insight: `half_life` ∈ volatile/seasonal/durable, `applies` ∈ local/homelab/universal, `claim_provenance` ∈ asserted/inferred — required together whenever either `half_life` or `applies` is set (an envelope with no provenance is rejected). A close-session insight is usually exactly the durable, generalizable, human-decided kind this describes: `half_life: durable, applies: universal, claim_provenance: asserted` is the common case, not a rare opt-in.
 - **`tickets[]`** — the issue actions from Phase 3: `{repo, action, ...}` where action ∈ create/close/comment. Owner is always `mathias` (server-forced).
 - **`context`** — `{harness: "claudeai-chat", session_ref: <chatid8-or-slug>, fidelity: "live-capture", actor: "mathias", classification: <see gate below>}`.
 
 **THE CLASSIFICATION GATE (read before calling — this is where capture refuses).**
 Capture computes an **effective classification = the strictest across EVERY target it touches** (each insight's `wing`, each ticket's `repo`), then refuses if that effective level is `confidential` and the origin is us-nexus (claude.ai is us-nexus). Levels come from `classification.yaml` at the brain root (source of truth, #67), with the code defaults as the floor: `hyperguild`/`homelab` → internal; `client-*` → confidential; **anything untagged → confidential (fail-safe)**.
-- **Tagged `internal` today** (safe through claude.ai): wings `hyperguild`, `homelab`; repos `brain`, `ai-sessions`, `infra`, `hyperguild`, `homelab`, `tapir`, `agentsquad`, `jepa-fx-risk`, `swedsl`. Treat `classification.yaml` as authoritative — this list is a hint, not gospel.
+- **The rule, not a list**: untagged → confidential (fail-safe). `classification.yaml` at the brain root is the sole authority on what's tagged `internal` today — it grew from 10 to ~39 repos in one sweep (hyperguild#91) and will keep moving, so read the file rather than trust an enumeration frozen at whatever moment this skill was last edited.
 - Declare `context.classification: "internal"` for normal homelab work.
 - Insight `wing`s and ticket `repo`s are classification INPUTS, not free-form metadata — every target must resolve `internal` or the whole capture escalates to `confidential` and the gate refuses via claude.ai. Listing the central homelab repos (incl. `brain`/`ai-sessions`) is now fine; they're tagged.
 - If a session genuinely touched **`client-*` or otherwise-untagged** material, it cannot be captured through claude.ai — note that in the verdict rather than trying to force it.