diff --git a/.omg/state/learn-watch.json b/.omg/state/learn-watch.json
deleted file mode 100644
index 34c2df8f7..000000000
--- a/.omg/state/learn-watch.json
+++ /dev/null
@@ -1,12 +0,0 @@
-{
-  "last_session_id": "67e970c5-7790-4d38-ba0b-527b9f349c49",
-  "last_event_key": "67e970c5-7790-4d38-ba0b-527b9f349c49:transcript:4fb7e8afb9c1c96fda3a464c707cde5137eba863cb21384f4d929867c14d1d9a",
-  "last_prompted_session_id": "",
-  "last_reason": "short-session",
-  "last_prompted_at": "",
-  "last_user_message_count": 0,
-  "last_actionable_message_count": 0,
-  "deep_interview_lock_active": false,
-  "deep_interview_lock_source": "/home/mhugo/code/singularity-forge/.omg/state/deep-interview.json",
-  "updated_at": "2026-05-04T20:36:06.661Z"
-}
diff --git a/packages/pi-ai/scripts/generate-models.ts b/packages/pi-ai/scripts/generate-models.ts
index 473912c5b..19dd846c7 100644
--- a/packages/pi-ai/scripts/generate-models.ts
+++ b/packages/pi-ai/scripts/generate-models.ts
@@ -719,6 +719,7 @@ async function generateModels() {
 		...aiGatewayModels,
 	].filter(
 		(model) =>
+			!model.id.endsWith("-customtools") &&
 			!(
 				(model.provider === "opencode" || model.provider === "opencode-go") &&
 				model.id === "gpt-5.3-codex-spark"
diff --git a/packages/pi-ai/src/models.test.ts b/packages/pi-ai/src/models.test.ts
index 24556a1e8..4bc7a4b66 100644
--- a/packages/pi-ai/src/models.test.ts
+++ b/packages/pi-ai/src/models.test.ts
@@ -18,6 +18,26 @@ import type { Api, Model } from "./types.js";
 // ═══════════════════════════════════════════════════════════════════════════
 
 describe("model registry — custom providers", () => {
+	it("hides Gemini customtools variants from the runtime registry", () => {
+		const googleModels = getModels("google").map((model) => model.id);
+		const geminiCliModels = getModels("google-gemini-cli").map(
+			(model) => model.id,
+		);
+
+		assert.equal(
+			googleModels.some((id) => id.endsWith("-customtools")),
+			false,
+		);
+		assert.equal(
+			geminiCliModels.some((id) => id.endsWith("-customtools")),
+			false,
+		);
+		assert.equal(
+			getModel("google" as any, "gemini-3.1-pro-preview-customtools" as any),
+			undefined,
+		);
+	});
+
 	it("alibaba-coding-plan is a registered provider", () => {
 		const providers = getProviders();
 		assert.ok(
diff --git a/packages/pi-ai/src/models.ts b/packages/pi-ai/src/models.ts
index e50fd3b76..d39cc3e7a 100644
--- a/packages/pi-ai/src/models.ts
+++ b/packages/pi-ai/src/models.ts
@@ -10,10 +10,15 @@ import type {
 
 const modelRegistry: Map<string, Map<string, Model<Api>>> = new Map();
 
+function isHiddenBuiltInModelId(id: string): boolean {
+	return id.endsWith("-customtools");
+}
+
 // Initialize registry from auto-generated MODELS (models.dev catalog)
 for (const [provider, models] of Object.entries(MODELS)) {
 	const providerModels = new Map<string, Model<Api>>();
 	for (const [id, model] of Object.entries(models)) {
+		if (isHiddenBuiltInModelId(id)) continue;
 		providerModels.set(id, model as Model<Api>);
 	}
 	modelRegistry.set(provider, providerModels);
diff --git a/packages/pi-ai/src/providers/google-gemini-cli.test.ts b/packages/pi-ai/src/providers/google-gemini-cli.test.ts
index c6c5a7711..e49d9f25e 100644
--- a/packages/pi-ai/src/providers/google-gemini-cli.test.ts
+++ b/packages/pi-ai/src/providers/google-gemini-cli.test.ts
@@ -5,6 +5,8 @@ import type { Context, Model } from "../types.js";
 const geminiCliCore = vi.hoisted(() => ({
 	retryError: undefined as Error | undefined,
 	retryOptions: undefined as Record<string, unknown> | undefined,
+	fakeConfigParams: undefined as Record<string, unknown> | undefined,
+	generatorAuthType: undefined as unknown,
 }));
 
 vi.mock("@google/gemini-cli-core", () => ({
@@ -15,7 +17,10 @@ vi.mock("@google/gemini-cli-core", () => ({
 		}
 	},
 	getOauthClient: vi.fn(async () => ({})),
-	makeFakeConfig: vi.fn(() => ({})),
+	makeFakeConfig: vi.fn((params: Record<string, unknown>) => {
+		geminiCliCore.fakeConfigParams = params;
+		return { params };
+	}),
 	retryWithBackoff: vi.fn(
 		async (_fn: unknown, options: Record<string, unknown>) => {
 			geminiCliCore.retryOptions = options;
@@ -25,6 +30,18 @@ vi.mock("@google/gemini-cli-core", () => ({
 	setupUser: vi.fn(async () => ({ projectId: "test-project" })),
 }));
 
+vi.mock("@google/gemini-cli-core/dist/src/core/contentGenerator.js", () => ({
+	createContentGeneratorConfig: vi.fn(async (_config, authType) => {
+		geminiCliCore.generatorAuthType = authType;
+		return { authType };
+	}),
+	createContentGenerator: vi.fn(async () => ({
+		async generateContentStream(): Promise<AsyncGenerator<unknown>> {
+			return (async function* emptyStream() {})();
+		},
+	})),
+}));
+
 import { streamGoogleGeminiCli } from "./google-gemini-cli.js";
 
 function makeModel(): Model<"google-gemini-cli"> {
@@ -65,6 +82,12 @@ describe("google-gemini-cli provider retry ownership", () => {
 			| { maxAttempts?: unknown }
 			| undefined;
 		assert.equal(retryOptions?.maxAttempts, 1);
+		assert.equal(
+			geminiCliCore.fakeConfigParams?.model,
+			"gemini-3-flash-preview",
+		);
+		assert.equal(geminiCliCore.fakeConfigParams?.clientName, undefined);
+		assert.equal(geminiCliCore.generatorAuthType, "LOGIN_WITH_GOOGLE");
 		assert.equal(result.stopReason, "error");
 		assert.match(result.errorMessage ?? "", /exhausted your capacity/i);
 		assert.equal(result.retryAfterMs, 54_000);
diff --git a/packages/pi-ai/src/providers/google-gemini-cli.ts b/packages/pi-ai/src/providers/google-gemini-cli.ts
index 12c2866f1..ee6599682 100644
--- a/packages/pi-ai/src/providers/google-gemini-cli.ts
+++ b/packages/pi-ai/src/providers/google-gemini-cli.ts
@@ -14,8 +14,11 @@ import {
 	makeFakeConfig,
 	retryWithBackoff,
 } from "@google/gemini-cli-core";
-import { createCodeAssistContentGenerator } from "@google/gemini-cli-core/dist/src/code_assist/codeAssist.js";
 import type { ContentGenerator } from "@google/gemini-cli-core/dist/src/core/contentGenerator.js";
+import {
+	createContentGenerator,
+	createContentGeneratorConfig,
+} from "@google/gemini-cli-core/dist/src/core/contentGenerator.js";
 import type {
 	Content,
 	GenerateContentParameters,
@@ -98,26 +101,27 @@ export interface GoogleGeminiCliOptions extends StreamOptions {
 let toolCallCounter = 0;
 
 /**
- * Build a Code Assist content generator using cli-core's own auth + project discovery.
+ * Build a Code Assist content generator using cli-core's official content-generator path.
  *
- * - getOauthClient() reads ~/.gemini/oauth_creds.json when present, refreshes if
- *   expired. cli-core owns any interactive login flow it needs.
- * - setupUser() asks the Code Assist API for the project + tier tied to this
- *   identity (free-tier auto-provisioned if needed; otherwise whatever the
- *   user has been onboarded to server-side).
- * - createCodeAssistContentGenerator() passes the returned tier and paid-tier
- *   data into CodeAssistServer, matching the official Gemini CLI path.
+ * Upstream Gemini CLI does not instantiate CodeAssistServer directly from the
+ * caller. It creates a ContentGeneratorConfig, lets createContentGenerator()
+ * build the GeminiCLI User-Agent and transport headers, then delegates to
+ * createCodeAssistContentGenerator() for OAuth, setupUser(), and Code Assist.
  *
  * Both calls memoize internally inside cli-core — repeat invocations are
  * cheap.
  */
-async function getCodeAssistServer(): Promise<ContentGenerator> {
-	const config = makeFakeConfig();
-	return createCodeAssistContentGenerator(
-		{ headers: {} },
-		AuthType.LOGIN_WITH_GOOGLE,
+async function getCodeAssistServer(modelId: string): Promise<ContentGenerator> {
+	const config = makeFakeConfig({
+		model: modelId,
+		cwd: process.cwd(),
+		targetDir: process.cwd(),
+	});
+	const generatorConfig = await createContentGeneratorConfig(
 		config,
+		AuthType.LOGIN_WITH_GOOGLE,
 	);
+	return createContentGenerator(generatorConfig, config);
 }
 
 function parseDurationMs(value: string): number | undefined {
@@ -213,14 +217,14 @@ export const streamGoogleGeminiCli: StreamFunction<
 		};
 
 		try {
-			// cli-core handles auth + project discovery. SF uses cli-core directly
-			// and does not spawn a separate provider CLI process.
-			const server = await getCodeAssistServer();
 			let req = buildRequest(model, context, options);
 			const nextReq = await options?.onPayload?.(req, model);
 			if (nextReq !== undefined) {
 				req = nextReq as GenerateContentParameters;
 			}
+			// cli-core handles auth + project discovery. SF uses cli-core directly
+			// and does not spawn a separate provider CLI process.
+			const server = await getCodeAssistServer(req.model);
 			const promptId = `pi-${Date.now()}-${Math.random().toString(36).slice(2, 11)}`;
 			// Cast through `any` — cli-core bundles its own nested @google/genai copy,
 			// so TypeScript sees two structurally-identical-but-distinct Content types.
diff --git a/src/resources/extensions/sf/agentic-docs-scaffold.js b/src/resources/extensions/sf/agentic-docs-scaffold.js
index e649075d6..c51b134b3 100644
--- a/src/resources/extensions/sf/agentic-docs-scaffold.js
+++ b/src/resources/extensions/sf/agentic-docs-scaffold.js
@@ -2,12 +2,16 @@ import {
 	existsSync,
 	mkdirSync,
 	readdirSync,
+	readFileSync,
 	rmdirSync,
 	rmSync,
 	writeFileSync,
 } from "node:fs";
 import { dirname, join } from "node:path";
-import { migrateLegacyScaffold } from "./scaffold-drift.js";
+import {
+	migrateLegacyGsdScaffold,
+	migrateLegacyScaffold,
+} from "./scaffold-drift.js";
 import {
 	bodyHash,
 	extractMarker,
@@ -29,6 +33,13 @@ const LEGACY_ROOT_HARNESS_PATHS = [
 	"harness/evals/AGENTS.md",
 	"harness/graders/AGENTS.md",
 ];
+const LEGACY_ROOT_HARNESS_TARGETS = {
+	"harness/AGENTS.md": ".sf/harness/AGENTS.md",
+	"harness/specs/AGENTS.md": ".sf/harness/specs/AGENTS.md",
+	"harness/specs/bootstrap.md": ".sf/harness/specs/bootstrap.md",
+	"harness/evals/AGENTS.md": ".sf/harness/evals/AGENTS.md",
+	"harness/graders/AGENTS.md": ".sf/harness/graders/AGENTS.md",
+};
 /**
  * Canonical scaffold file templates SF manages for agent legibility.
  *
@@ -501,16 +512,34 @@ function pruneEmptyDir(path) {
 	}
 }
 
+function scaffoldContentForPath(relPath) {
+	return SCAFFOLD_FILES.find((file) => file.path === relPath)?.content ?? null;
+}
+
+function isUnmarkedGeneratedRootHarness(relPath, body) {
+	const currentRelPath = LEGACY_ROOT_HARNESS_TARGETS[relPath];
+	const currentContent = currentRelPath
+		? scaffoldContentForPath(currentRelPath)
+		: null;
+	if (!currentContent) return false;
+	return body.trim() === currentContent.trim();
+}
+
 function removeLegacyRootHarnessScaffold(basePath) {
 	for (const relPath of LEGACY_ROOT_HARNESS_PATHS) {
 		const target = join(basePath, relPath);
 		try {
 			if (!existsSync(target)) continue;
 			const { marker, body } = extractMarker(target);
-			if (!marker) continue;
-			if (marker.template !== relPath) continue;
-			if (marker.state !== "pending") continue;
-			if (bodyHash(body) !== marker.hash) continue;
+			if (marker) {
+				if (marker.template !== relPath) continue;
+				if (marker.state !== "pending") continue;
+				if (bodyHash(body) !== marker.hash) continue;
+			} else if (
+				!isUnmarkedGeneratedRootHarness(relPath, readFileSync(target, "utf-8"))
+			) {
+				continue;
+			}
 			rmSync(target);
 		} catch (err) {
 			logWarning("scaffold", "failed to remove legacy root harness file", {
@@ -554,6 +583,13 @@ export function ensureAgenticDocsScaffold(basePath) {
 			error: err.message,
 		});
 	}
+	try {
+		migrateLegacyGsdScaffold(basePath);
+	} catch (err) {
+		logWarning("scaffold", "legacy GSD migration failed", {
+			error: err.message,
+		});
+	}
 	removeLegacyRootHarnessScaffold(basePath);
 	// Step 2: missing-file creation + pending-state silent upgrade.
 	for (const file of SCAFFOLD_FILES) {
diff --git a/src/resources/extensions/sf/scaffold-drift.js b/src/resources/extensions/sf/scaffold-drift.js
index 5171096eb..f6a5cba4e 100644
--- a/src/resources/extensions/sf/scaffold-drift.js
+++ b/src/resources/extensions/sf/scaffold-drift.js
@@ -6,7 +6,7 @@
  * buckets. The result is structured and side-effect-free — Phase C wires
  * the report into the scaffold sync pipeline; Phase B is data-plane only.
  */
-import { existsSync, readFileSync } from "node:fs";
+import { existsSync, readFileSync, writeFileSync } from "node:fs";
 import { join } from "node:path";
 import { SCAFFOLD_FILES } from "./agentic-docs-scaffold.js";
 import {
@@ -48,8 +48,46 @@ function emptyCounts() {
 		"editing-drift": 0,
 		untracked: 0,
 		current: 0,
+		customized: 0,
 	};
 }
+
+const LEGACY_GSD_MANAGED_MARKER_RE = /<!--\s*\/?GSD:/i;
+
+/**
+ * Return true when a marker-less scaffold file still contains old managed GSD
+ * section markers.
+ *
+ * Purpose: let scaffold sync identify generated legacy guidance in projects
+ * that predate ADR-021's `sf-doc` marker without treating arbitrary prose as
+ * safe to rewrite.
+ *
+ * Consumer: detectScaffoldDrift and migrateLegacyGsdScaffold.
+ */
+export function hasLegacyGsdManagedMarkers(body) {
+	return LEGACY_GSD_MANAGED_MARKER_RE.test(body);
+}
+
+/**
+ * Rewrite legacy GSD-generated scaffold text to SF naming.
+ *
+ * Purpose: preserve repo-local custom prose while removing obsolete product
+ * names from sections that carry old managed GSD markers.
+ *
+ * Consumer: migrateLegacyGsdScaffold during startup and `/sf scaffold sync`.
+ */
+export function rewriteLegacyGsdManagedBody(body) {
+	return body
+		.replace(/<!--\s*GSD:/g, "<!-- SF:")
+		.replace(/<!--\s*\/GSD:/g, "<!-- /SF:")
+		.replace(/\.gsd\//g, ".sf/")
+		.replace(/\.gsd\b/g, ".sf")
+		.replace(/\/gsd-([a-z0-9-]+)/gi, "/sf $1")
+		.replace(/\bgsd\s+headless\s+auto\b/gi, "sf headless auto")
+		.replace(/\bgsd\s+auto\b/gi, "sf autonomous")
+		.replace(/\bGSD\b/g, "SF")
+		.replace(/\bgsd\b/g, "sf");
+}
 /**
  * Classify every `SCAFFOLD_FILES` entry against its on-disk state.
  *
@@ -127,6 +165,19 @@ export function detectScaffoldDrift(basePath) {
 					body = "";
 				}
 			}
+			if (hasLegacyGsdManagedMarkers(body)) {
+				items.push({
+					path: file.path,
+					template: file.path,
+					bucket: "upgradable",
+					currentVersion: "legacy-gsd",
+					shipVersion,
+					hashDrifted: false,
+					legacyMigration: "gsd-managed-markers",
+				});
+				counts.upgradable += 1;
+				continue;
+			}
 			items.push({
 				path: file.path,
 				template: file.path,
@@ -333,3 +384,62 @@ export function migrateLegacyScaffold(basePath) {
 	}
 	return { migrated, skipped };
 }
+
+/**
+ * Upgrade marker-less scaffold files that still carry legacy GSD managed
+ * section markers.
+ *
+ * Purpose: make `/sf scaffold sync` responsible for stale generated SF/GSD
+ * guidance without overwriting repo-specific content around those sections.
+ *
+ * Consumer: ensureAgenticDocsScaffold before normal missing-file and pending
+ * version refresh handling.
+ */
+export function migrateLegacyGsdScaffold(basePath) {
+	const shipVersion = process.env.SF_VERSION || "0.0.0";
+	const migrated = [];
+	const skipped = [];
+	const appliedAt = new Date().toISOString();
+	for (const file of SCAFFOLD_FILES) {
+		if (SKIP_MARKER_PATHS.has(file.path)) continue;
+		const target = join(basePath, file.path);
+		if (!existsSync(target)) continue;
+		let body;
+		let markerPresent = false;
+		try {
+			const extracted = extractMarker(target);
+			markerPresent = extracted.marker !== null;
+			body = extracted.body;
+		} catch (err) {
+			logWarning("scaffold", "failed to read file during GSD migration", {
+				file: file.path,
+				error: err.message,
+			});
+			skipped.push(file.path);
+			continue;
+		}
+		if (markerPresent) continue;
+		if (!hasLegacyGsdManagedMarkers(body)) continue;
+		const upgraded = rewriteLegacyGsdManagedBody(body);
+		try {
+			writeFileSync(target, upgraded, "utf-8");
+			stampScaffoldFile(target, file.path, shipVersion, "completed");
+			recordScaffoldApply(basePath, {
+				path: file.path,
+				template: file.path,
+				version: shipVersion,
+				appliedAt,
+				stateAtApply: "completed",
+				contentHash: bodyHash(upgraded),
+			});
+			migrated.push(file.path);
+		} catch (err) {
+			logWarning("scaffold", "failed to upgrade legacy GSD scaffold file", {
+				file: file.path,
+				error: err.message,
+			});
+			skipped.push(file.path);
+		}
+	}
+	return { migrated, skipped };
+}
diff --git a/src/resources/extensions/sf/tests/agentic-docs-scaffold.test.mjs b/src/resources/extensions/sf/tests/agentic-docs-scaffold.test.mjs
index c7df6b7f9..a1c988f5f 100644
--- a/src/resources/extensions/sf/tests/agentic-docs-scaffold.test.mjs
+++ b/src/resources/extensions/sf/tests/agentic-docs-scaffold.test.mjs
@@ -10,7 +10,8 @@ import { tmpdir } from "node:os";
 import { dirname, join } from "node:path";
 import { afterEach, test } from "vitest";
 import { ensureAgenticDocsScaffold } from "../agentic-docs-scaffold.js";
-import { stampScaffoldFile } from "../scaffold-versioning.js";
+import { detectScaffoldDrift } from "../scaffold-drift.js";
+import { extractMarker, stampScaffoldFile } from "../scaffold-versioning.js";
 
 const tmpRoots = [];
 
@@ -42,3 +43,91 @@ test("ensureAgenticDocsScaffold_removes_owned_root_harness_and_writes_sf_harness
 	assert.equal(existsSync(join(root, "harness")), false);
 	assert.equal(existsSync(join(root, ".sf/harness/specs/bootstrap.md")), true);
 });
+
+test("detectScaffoldDrift_when_unmarked_gsd_managed_section_marks_upgradable", () => {
+	const root = makeProject();
+	const target = join(root, "AGENTS.md");
+	writeFileSync(
+		target,
+		[
+			"# Local Agents",
+			"",
+			"<!-- GSD:project-start source:PROJECT.md -->",
+			"Run `gsd headless auto` and keep `.gsd/` state current.",
+			"<!-- /GSD:project-end -->",
+			"",
+		].join("\n"),
+		"utf-8",
+	);
+
+	const item = detectScaffoldDrift(root).items.find(
+		(candidate) => candidate.path === "AGENTS.md",
+	);
+
+	assert.equal(item.bucket, "upgradable");
+	assert.equal(item.legacyMigration, "gsd-managed-markers");
+});
+
+test("ensureAgenticDocsScaffold_rewrites_and_stamps_legacy_gsd_managed_section", () => {
+	const root = makeProject();
+	const target = join(root, "AGENTS.md");
+	writeFileSync(
+		target,
+		[
+			"# Local Agents",
+			"",
+			"Keep this repo note.",
+			"<!-- GSD:project-start source:PROJECT.md -->",
+			"Run `gsd headless auto` and keep `.gsd/` state current.",
+			"<!-- /GSD:project-end -->",
+			"",
+		].join("\n"),
+		"utf-8",
+	);
+
+	ensureAgenticDocsScaffold(root);
+
+	const { marker, body } = extractMarker(target);
+	assert.equal(marker?.state, "completed");
+	assert.equal(marker?.template, "AGENTS.md");
+	assert.match(body, /Keep this repo note\./);
+	assert.match(body, /<!-- SF:project-start source:PROJECT\.md -->/);
+	assert.match(body, /sf headless auto/);
+	assert.match(body, /\.sf\//);
+	assert.doesNotMatch(body, /GSD|gsd|\.gsd/);
+});
+
+test("ensureAgenticDocsScaffold_removes_unmarked_generated_root_harness", () => {
+	const root = makeProject();
+	const target = join(root, "harness/specs/bootstrap.md");
+	mkdirSync(dirname(target), { recursive: true });
+	writeFileSync(
+		target,
+		`# Bootstrap Spec: Agent Legibility
+
+Verifies that this repo is minimally agent-legible.
+
+## Criteria
+
+- [ ] \`AGENTS.md\` exists at repo root and is non-empty.
+- [ ] \`ARCHITECTURE.md\` exists at repo root and is non-empty.
+- [ ] \`docs/exec-plans/active/\` exists.
+- [ ] \`docs/exec-plans/tech-debt-tracker.md\` exists.
+- [ ] \`docs/design-docs/ADR-TEMPLATE.md\` exists.
+
+## Verification command
+
+\`\`\`bash
+for f in AGENTS.md ARCHITECTURE.md docs/exec-plans/active/index.md docs/exec-plans/tech-debt-tracker.md docs/design-docs/ADR-TEMPLATE.md .sf/harness/specs/bootstrap.md; do [ -s "$f" ] && echo "OK: $f" || echo "MISSING: $f"; done
+\`\`\`
+
+All lines should start with \`OK:\` for the bootstrap spec to pass.
+`,
+		"utf-8",
+	);
+
+	ensureAgenticDocsScaffold(root);
+
+	assert.equal(existsSync(join(root, "harness")), false);
+	assert.equal(existsSync(join(root, ".sf/harness/specs/bootstrap.md")), true);
+});