feat(canvas): P3 internal#718 — consume registry-served /templates list, retire hardcoded provider vocab (#4/#5)

P3 item 2. The canvas Provider/Model selector + Config-tab billing-mode now
consume the registry-served GET /templates fields (registry_backed /
registry_providers / registry_models from PR-A) instead of re-deriving provider
knowledge client-side. Retires the hardcoded vocabularies as the PRIMARY path:

- ProviderModelSelector (#4): new buildProviderCatalogFromRegistry(providers,
  models) builds the dropdown catalog from the registry payload — provider
  label = registry display_name, bucket = DERIVED provider, billing + auth_env
  from the registry — instead of inferVendor / VENDOR_LABELS /
  BARE_VENDOR_PATTERNS. The selector takes an optional pre-built `catalog`
  prop and uses it verbatim when supplied. inferVendor/buildProviderCatalog
  remain ONLY as the fallback for non-registry runtimes / older backends.
- ConfigTab (#5): when the selected runtime is registry-backed, the provider
  catalog + selector models come from registry_providers/registry_models, and
  billingModeForSelectedProvider(provider, catalog) reads the DERIVED provider's
  billing_mode off the registry catalog. The hardcoded billingModeForProvider
  ('' | 'platform' → platform_managed else byok) stays as the fallback only.
  So the billing-mode the UI shows/sends reflects the DERIVED provider
  (folds in the closed #1931's canvas intent).

Federation/back-compat preserved: a non-registry runtime (external/mock/kimi/
future third-party) or an older backend that doesn't serve the registry fields
yields registry_backed=false → the canvas keeps the template-served models +
its heuristic, unchanged. NO hard-reject (the canvas just can't render an
option the registry didn't serve for registry-backed runtimes).

Out of scope (per brief): the manifest runtime allowlist
(SUPPORTED_RUNTIME_VALUES / FALLBACK_RUNTIME_OPTIONS) is NOT a provider
vocabulary and is untouched; PUT /workspaces/:id/provider is NOT retired (that
CTO #3 follow-through is a later phase).

Stacked on PR-A (workspace-server registry-served /templates); re-target to
main after PR-A merges.

TDD: ProviderModelSelector.registry.test.tsx (catalog bucketed by derived
provider, labelled from display_name, carries billing_mode + auth_env, no empty
buckets), ConfigTab.registryBilling.test.tsx (billing reads registry catalog;
falls back to the legacy rule with no catalog / unknown provider). Full canvas
suite green (3380 passed / 1 skipped), tsc clean for touched files, eslint 0.

internal#718 P3 — not merged; CTO merge-go after Five-Axis (UI-affecting).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

canvas/src/components/ProviderModelSelector.tsx

@@ -49,6 +49,33 @@ export interface ProviderEntry {
   wildcard: boolean;
   /** Optional tooltip text (rendered as native title=). */
   tooltip?: string;
+  /** Billing mode the DERIVED provider implies, when this entry came from the
+   *  registry-backed payload (internal#718 P3): "platform_managed" | "byok".
+   *  Undefined for entries built by the legacy inferVendor heuristic. */
+  billingMode?: "platform_managed" | "byok";
+}
+
+/** RegistryProvider mirrors one entry of GET /templates `registry_providers`
+ *  (workspace-server registryProviderView): the registry's native provider for
+ *  a runtime, with its display label, auth-env NAMES, and billing mode. This is
+ *  the SSOT the dropdown labels come from — the canvas drops VENDOR_LABELS for
+ *  registry-backed runtimes (internal#718 P3, retire-list #4). */
+export interface RegistryProvider {
+  name: string;
+  display_name?: string;
+  auth_env?: string[];
+  billing_mode?: "platform_managed" | "byok";
+  deprecated?: boolean;
+}
+
+/** RegistryModel mirrors one entry of GET /templates `registry_models`: a
+ *  native model id annotated with its DERIVED provider (registry name) and the
+ *  billing_mode that provider implies. */
+export interface RegistryModel {
+  id: string;
+  name?: string;
+  provider?: string;
+  billing_mode?: "platform_managed" | "byok";
 }
 
 export interface SelectorValue {
@@ -68,6 +95,13 @@ interface Props {
   models: SelectorModel[];
   value: SelectorValue;
   onChange: (next: SelectorValue) => void;
+  /** Optional pre-built provider catalog. When provided, the selector uses it
+   *  verbatim instead of re-inferring one from `models` via
+   *  buildProviderCatalog — the registry-backed path (internal#718 P3), where
+   *  the parent builds the catalog from the registry-served providers/models
+   *  so dropdown labels + billing come from the provider-registry SSOT rather
+   *  than the inferVendor heuristic. Omitted = legacy heuristic over `models`. */
+  catalog?: ProviderEntry[];
   /** Display variant. "grid" = label+control side-by-side (used in ConfigTab
    *  Runtime section). "stack" = vertical (used in MissingKeysModal). */
   variant?: "grid" | "stack";
@@ -251,6 +285,66 @@ export function buildProviderCatalog(models: SelectorModel[]): ProviderEntry[] {
   return Array.from(buckets.values());
 }
 
+/** Build the provider catalog from a REGISTRY-BACKED GET /templates payload
+ *  (registry_providers + registry_models) — internal#718 P3, retire-list #4.
+ *
+ *  Unlike buildProviderCatalog (which RE-INFERS vendor from model-id prefixes
+ *  + env via inferVendor/VENDOR_LABELS/BARE_VENDOR_PATTERNS), this trusts the
+ *  registry: each model carries its DERIVED `provider` (a registry provider
+ *  name) and the dropdown label/billing/auth come from the matching
+ *  `registry_providers` entry. The canvas can render no provider/model the
+ *  registry did not serve ("only registered selectable"), and the billing-mode
+ *  shown reflects the derived provider rather than a hardcoded rule.
+ *
+ *  A provider with no served model is omitted (no empty buckets). Models whose
+ *  `provider` doesn't match a registry_providers entry still get a bucket
+ *  keyed by the raw provider name (defensive — should not happen for a
+ *  well-formed registry payload), so a model is never silently dropped. */
+export function buildProviderCatalogFromRegistry(
+  registryProviders: RegistryProvider[],
+  registryModels: RegistryModel[],
+): ProviderEntry[] {
+  const byName = new Map<string, RegistryProvider>();
+  for (const p of registryProviders) byName.set(p.name, p);
+
+  // Bucket models by their derived provider name, preserving registry order.
+  const buckets = new Map<string, ProviderEntry>();
+  for (const m of registryModels) {
+    const vendor = (m.provider ?? "").trim();
+    if (!vendor) continue; // un-annotated registry model — skip from the
+    // provider cascade (selectable elsewhere via free-text); it has no
+    // derived provider to bucket under.
+    const meta = byName.get(vendor);
+    const wildcard = m.id.includes("*");
+    let entry = buckets.get(vendor);
+    if (!entry) {
+      entry = {
+        id: `registry|${vendor}`,
+        vendor,
+        label: meta?.display_name || vendor,
+        envVars: meta?.auth_env ?? [],
+        models: [],
+        wildcard,
+        billingMode: meta?.billing_mode ?? m.billing_mode,
+        tooltip: VENDOR_TOOLTIPS[vendor],
+      };
+      buckets.set(vendor, entry);
+    }
+    entry.models.push({ id: m.id, name: m.name, provider: vendor });
+    entry.wildcard = entry.wildcard || wildcard;
+  }
+
+  // Decorate label with model-count when ≥2 concrete models share the bucket,
+  // matching buildProviderCatalog's UX.
+  for (const e of buckets.values()) {
+    if (!e.wildcard && e.models.length > 1) {
+      e.label = `${e.label} (${e.models.length} models)`;
+    }
+  }
+
+  return Array.from(buckets.values());
+}
+
 /** Find the provider entry that contains a given model id. Used by
  *  callers to back-derive the provider when only the model is known
  *  (e.g. ConfigTab loading from saved state). */
@@ -283,6 +377,7 @@ export function ProviderModelSelector({
   models,
   value,
   onChange,
+  catalog: catalogProp,
   variant = "stack",
   allowCustomModelEscape = false,
   disabled = false,
@@ -293,7 +388,12 @@ export function ProviderModelSelector({
   const providerSelectId = `${baseId}-provider`;
   const modelSelectId = `${baseId}-model`;
 
-  const catalog = useMemo(() => buildProviderCatalog(models), [models]);
+  // Registry-backed path (internal#718 P3): use the parent-supplied catalog
+  // verbatim; otherwise re-infer one from `models` via the legacy heuristic.
+  const catalog = useMemo(
+    () => catalogProp ?? buildProviderCatalog(models),
+    [catalogProp, models],
+  );
   const selected = useMemo(
     () => catalog.find((p) => p.id === value.providerId) ?? null,
     [catalog, value.providerId],

canvas/src/components/__tests__/ProviderModelSelector.registry.test.tsx

@@ -0,0 +1,110 @@
+// @vitest-environment jsdom
+//
+// internal#718 P3 (retire-list #4) — when GET /templates serves a
+// registry-backed selectable list (registry_providers + registry_models with
+// display_name / billing_mode / derived provider), the canvas builds the
+// provider catalog FROM that registry data instead of re-inferring vendor
+// from model-id prefixes (VENDOR_LABELS / BARE_VENDOR_PATTERNS / inferVendor).
+// The heuristic path stays only as the fallback for non-registry runtimes /
+// older backends.
+
+import { describe, it, expect } from "vitest";
+import {
+  buildProviderCatalogFromRegistry,
+  type RegistryProvider,
+  type RegistryModel,
+} from "../ProviderModelSelector";
+
+// Mirrors the registry-served claude-code payload from GET /templates
+// (registry_providers / registry_models). display_name + billing_mode come
+// from the registry, NOT from the canvas VENDOR_LABELS map.
+const CLAUDE_CODE_REGISTRY_PROVIDERS: RegistryProvider[] = [
+  {
+    name: "anthropic-oauth",
+    display_name: "Claude Code subscription",
+    auth_env: ["CLAUDE_CODE_OAUTH_TOKEN"],
+    billing_mode: "byok",
+  },
+  {
+    name: "anthropic-api",
+    display_name: "Anthropic API",
+    auth_env: ["ANTHROPIC_API_KEY"],
+    billing_mode: "byok",
+  },
+  {
+    name: "platform",
+    display_name: "Platform",
+    auth_env: ["ANTHROPIC_API_KEY", "MOLECULE_LLM_USAGE_TOKEN"],
+    billing_mode: "platform_managed",
+  },
+];
+
+const CLAUDE_CODE_REGISTRY_MODELS: RegistryModel[] = [
+  { id: "sonnet", provider: "anthropic-oauth", billing_mode: "byok" },
+  { id: "opus", provider: "anthropic-oauth", billing_mode: "byok" },
+  { id: "claude-opus-4-7", provider: "anthropic-api", billing_mode: "byok" },
+  { id: "anthropic/claude-opus-4-7", provider: "platform", billing_mode: "platform_managed" },
+];
+
+describe("buildProviderCatalogFromRegistry", () => {
+  it("buckets models by their DERIVED registry provider, not by inferred vendor", () => {
+    const catalog = buildProviderCatalogFromRegistry(
+      CLAUDE_CODE_REGISTRY_PROVIDERS,
+      CLAUDE_CODE_REGISTRY_MODELS,
+    );
+
+    const byVendor = new Map(catalog.map((p) => [p.vendor, p]));
+    // anthropic-oauth bucket holds the two OAuth-derived models.
+    const oauth = byVendor.get("anthropic-oauth");
+    expect(oauth).toBeDefined();
+    expect(oauth!.models.map((m) => m.id).sort()).toEqual(["opus", "sonnet"]);
+    // platform bucket holds the platform-namespaced model.
+    const platform = byVendor.get("platform");
+    expect(platform).toBeDefined();
+    expect(platform!.models.map((m) => m.id)).toEqual(["anthropic/claude-opus-4-7"]);
+  });
+
+  it("labels providers from the registry display_name, not VENDOR_LABELS", () => {
+    const catalog = buildProviderCatalogFromRegistry(
+      CLAUDE_CODE_REGISTRY_PROVIDERS,
+      CLAUDE_CODE_REGISTRY_MODELS,
+    );
+    const oauth = catalog.find((p) => p.vendor === "anthropic-oauth");
+    // Registry display_name "Claude Code subscription" (decorated with the
+    // model count by the catalog builder is acceptable; assert it carries the
+    // registry label, not an inferred one).
+    expect(oauth!.label).toContain("Claude Code subscription");
+  });
+
+  it("carries the registry billing_mode per provider", () => {
+    const catalog = buildProviderCatalogFromRegistry(
+      CLAUDE_CODE_REGISTRY_PROVIDERS,
+      CLAUDE_CODE_REGISTRY_MODELS,
+    );
+    expect(catalog.find((p) => p.vendor === "anthropic-oauth")!.billingMode).toBe("byok");
+    expect(catalog.find((p) => p.vendor === "platform")!.billingMode).toBe("platform_managed");
+  });
+
+  it("surfaces the registry auth_env on the provider entry", () => {
+    const catalog = buildProviderCatalogFromRegistry(
+      CLAUDE_CODE_REGISTRY_PROVIDERS,
+      CLAUDE_CODE_REGISTRY_MODELS,
+    );
+    expect(catalog.find((p) => p.vendor === "anthropic-oauth")!.envVars).toEqual([
+      "CLAUDE_CODE_OAUTH_TOKEN",
+    ]);
+  });
+
+  it("only includes providers that actually have at least one served model", () => {
+    // anthropic-api is a registry provider but has no model in this slice →
+    // it should not appear as an empty bucket.
+    const models: RegistryModel[] = [
+      { id: "sonnet", provider: "anthropic-oauth", billing_mode: "byok" },
+    ];
+    const catalog = buildProviderCatalogFromRegistry(
+      CLAUDE_CODE_REGISTRY_PROVIDERS,
+      models,
+    );
+    expect(catalog.map((p) => p.vendor)).toEqual(["anthropic-oauth"]);
+  });
+});

canvas/src/components/tabs/ConfigTab.tsx

@@ -11,8 +11,12 @@ import { ExternalConnectionSection } from "./ExternalConnectionSection";
 import {
   ProviderModelSelector,
   buildProviderCatalog,
+  buildProviderCatalogFromRegistry,
   findProviderForModel,
   type SelectorValue,
+  type ProviderEntry,
+  type RegistryProvider,
+  type RegistryModel,
 } from "../ProviderModelSelector";
 import { isExternalLikeRuntime } from "@/lib/externalRuntimes";
 
@@ -258,6 +262,17 @@ interface RuntimeOption {
   // canvas falls back to deriving unique vendor prefixes from
   // models[].id (still adapter-driven, just inferred).
   providers: string[];
+  // registryBacked / registryProviders / registryModels come from the
+  // registry-served GET /templates fields (internal#718 P3). When
+  // registryBacked is true, the selectable provider+model list is built from
+  // the registry (registryProviders/registryModels) — display labels +
+  // billing mode + derived provider come from the provider-registry SSOT, not
+  // the canvas VENDOR_LABELS / billingModeForProvider vocabularies. When
+  // false (non-registry runtime / older backend), the canvas falls back to
+  // the template-served models[] + its inferVendor heuristic.
+  registryBacked: boolean;
+  registryProviders: RegistryProvider[];
+  registryModels: RegistryModel[];
 }
 
 // deriveProvidersFromModels — when a template doesn't ship an explicit
@@ -322,6 +337,32 @@ export function billingModeForProvider(provider: string): LLMBillingMode {
   return "byok";
 }
 
+// billingModeForSelectedProvider — internal#718 P3 (retire-list #5): the
+// billing mode the Config tab shows/sends for the selected PROVIDER, sourced
+// from the registry-served catalog when available rather than the hardcoded
+// billingModeForProvider rule.
+//
+// When the runtime is registry-backed, GET /templates serves each provider's
+// DERIVED billing_mode (platform_managed for the closed platform provider,
+// byok otherwise) on the ProviderEntry. We read it off the catalog so the UI
+// reflects the registry SSOT — the same predicate billing/credential emission
+// keys off the derived provider.
+//
+// Falls back to billingModeForProvider when: no catalog (non-registry runtime
+// / older backend), or the provider string isn't carried by the catalog
+// (e.g. a stale saved value). The fallback keeps the legacy behavior intact
+// for everything the registry doesn't yet speak to.
+export function billingModeForSelectedProvider(
+  provider: string,
+  catalog?: ProviderEntry[],
+): LLMBillingMode {
+  if (catalog && catalog.length > 0) {
+    const entry = catalog.find((p) => p.vendor === provider.trim());
+    if (entry?.billingMode) return entry.billingMode;
+  }
+  return billingModeForProvider(provider);
+}
+
 // Fallback used when /templates can't be fetched (offline, older backend).
 // Keep in sync with manifest.json workspace_templates as a defensive default.
 // Model + env suggestions only flow when the backend is reachable.
@@ -339,10 +380,10 @@ const RUNTIMES_WITH_OWN_CONFIG = new Set<string>(["external", "kimi", "kimi-cli"
 const SUPPORTED_RUNTIME_VALUES = new Set(["claude-code", "codex", "openclaw", "hermes"]);
 
 const FALLBACK_RUNTIME_OPTIONS: RuntimeOption[] = [
-  { value: "claude-code", label: "Claude Code", models: [], providers: [] },
-  { value: "codex", label: "Codex", models: [], providers: [] },
-  { value: "openclaw", label: "OpenClaw", models: [], providers: [] },
-  { value: "hermes", label: "Hermes", models: [], providers: [] },
+  { value: "claude-code", label: "Claude Code", models: [], providers: [], registryBacked: false, registryProviders: [], registryModels: [] },
+  { value: "codex", label: "Codex", models: [], providers: [], registryBacked: false, registryProviders: [], registryModels: [] },
+  { value: "openclaw", label: "OpenClaw", models: [], providers: [], registryBacked: false, registryProviders: [], registryModels: [] },
+  { value: "hermes", label: "Hermes", models: [], providers: [], registryBacked: false, registryProviders: [], registryModels: [] },
 ];
 
 export function ConfigTab({ workspaceId }: Props) {
@@ -527,7 +568,18 @@ export function ConfigTab({ workspaceId }: Props) {
 
   useEffect(() => {
     let cancelled = false;
-    api.get<Array<{ id: string; name?: string; runtime?: string; models?: ModelSpec[]; providers?: string[] }>>("/templates")
+    api.get<Array<{
+      id: string;
+      name?: string;
+      runtime?: string;
+      models?: ModelSpec[];
+      providers?: string[];
+      // internal#718 P3 registry-served fields (additive; absent on older
+      // backends and for non-registry runtimes).
+      registry_backed?: boolean;
+      registry_providers?: RegistryProvider[];
+      registry_models?: RegistryModel[];
+    }>>("/templates")
       .then((rows) => {
         if (cancelled || !Array.isArray(rows)) return;
         const byRuntime = new Map<string, RuntimeOption>();
@@ -539,8 +591,23 @@ export function ConfigTab({ workspaceId }: Props) {
           const existing = byRuntime.get(v);
           const models = Array.isArray(r.models) ? r.models : [];
           const providers = Array.isArray(r.providers) ? r.providers : [];
-          if (!existing || models.length > existing.models.length) {
-            byRuntime.set(v, { value: v, label: r.name || v, models, providers });
+          const registryProviders = Array.isArray(r.registry_providers) ? r.registry_providers : [];
+          const registryModels = Array.isArray(r.registry_models) ? r.registry_models : [];
+          const registryBacked = r.registry_backed === true && registryModels.length > 0;
+          // Prefer the richer payload: a registry-backed entry, then more
+          // template models. Keeps the "last/richer template wins" intent.
+          const score = (o: RuntimeOption) => (o.registryBacked ? 1000 : 0) + o.models.length;
+          const candidate: RuntimeOption = {
+            value: v,
+            label: r.name || v,
+            models,
+            providers,
+            registryBacked,
+            registryProviders,
+            registryModels,
+          };
+          if (!existing || score(candidate) > score(existing)) {
+            byRuntime.set(v, candidate);
           }
         }
         if (byRuntime.size > 0) setRuntimeOptions(Array.from(byRuntime.values()));
@@ -551,7 +618,13 @@ export function ConfigTab({ workspaceId }: Props) {
 
   // Models + env hints for the currently-selected runtime.
   const selectedRuntime = runtimeOptions.find((o) => o.value === (config.runtime || "")) ?? null;
-  const availableModels: ModelSpec[] = selectedRuntime?.models ?? [];
+  // Memoised so its identity is stable across renders — it feeds several
+  // useMemo dependency arrays below (registry/legacy catalog, selector models)
+  // and a fresh `[]` literal each render would defeat their memoisation.
+  const availableModels: ModelSpec[] = useMemo(
+    () => selectedRuntime?.models ?? [],
+    [selectedRuntime?.models],
+  );
   // Provider suggestions for the legacy free-text input fallback (used
   // when /templates returned no models for this runtime, e.g. hermes
   // workspaces). Prefer the runtime's declarative providers list,
@@ -565,9 +638,37 @@ export function ConfigTab({ workspaceId }: Props) {
 
   // Vendor-aware catalog shared with the selector. Memoised so the
   // catalog identity is stable across renders (selector relies on it).
+  //
+  // internal#718 P3: when the runtime is registry-backed, build the catalog
+  // FROM the registry-served providers/models (display labels + billing +
+  // derived provider from the provider-registry SSOT) instead of re-inferring
+  // vendor from model-id prefixes. Falls back to the inferVendor heuristic
+  // for non-registry runtimes / older backends.
+  const registryBacked = selectedRuntime?.registryBacked ?? false;
   const providerCatalog = useMemo(
-    () => buildProviderCatalog(availableModels),
-    [availableModels],
+    () =>
+      registryBacked
+        ? buildProviderCatalogFromRegistry(
+            selectedRuntime?.registryProviders ?? [],
+            selectedRuntime?.registryModels ?? [],
+          )
+        : buildProviderCatalog(availableModels),
+    [registryBacked, selectedRuntime?.registryProviders, selectedRuntime?.registryModels, availableModels],
+  );
+  // Models fed to the selector dropdown: the registry-served native set for a
+  // registry-backed runtime (so the dropdown can render no unregistered
+  // option), else the template-served models.
+  const selectorModels: ModelSpec[] = useMemo(
+    () =>
+      registryBacked
+        ? (selectedRuntime?.registryModels ?? []).map((m) => ({
+            id: m.id,
+            name: m.name,
+            // carry the derived provider so the selector buckets correctly
+            ...(m.provider ? { provider: m.provider } : {}),
+          }))
+        : availableModels,
+    [registryBacked, selectedRuntime?.registryModels, availableModels],
   );
 
   // Derive the selector's current value from the form state. Provider
@@ -751,8 +852,13 @@ export function ConfigTab({ workspaceId }: Props) {
       // platform_managed→byok PUT and trigger a needless restart.
       let billingModeSaveError: string | null = null;
       if (providerChanged && !providerSaveError) {
-        const nextMode = billingModeForProvider(provider);
-        const prevMode = billingModeForProvider(originalProvider);
+        // internal#718 P3: derive the billing mode from the registry-served
+        // catalog when the runtime is registry-backed (the DERIVED provider's
+        // billing source is the SSOT), falling back to the legacy
+        // billingModeForProvider rule for non-registry runtimes / older
+        // backends.
+        const nextMode = billingModeForSelectedProvider(provider, providerCatalog);
+        const prevMode = billingModeForSelectedProvider(originalProvider, providerCatalog);
         if (nextMode !== prevMode) {
           try {
             await api.put(
@@ -918,9 +1024,10 @@ export function ConfigTab({ workspaceId }: Props) {
                 — empty = "auto-derive from model slug" was the pre-PR-5
                 behavior; selecting any provider here writes LLM_PROVIDER
                 and triggers an auto-restart. */}
-            {availableModels.length > 0 ? (
+            {selectorModels.length > 0 ? (
               <ProviderModelSelector
-                models={availableModels}
+                models={selectorModels}
+                catalog={registryBacked ? providerCatalog : undefined}
                 value={selectorValue}
                 onChange={(next) => {
                   setSelectorValue(next);
@@ -933,7 +1040,7 @@ export function ConfigTab({ workspaceId }: Props) {
                   setConfig((prev) => {
                     const v = next.model;
                     const prevModelId = prev.runtime_config?.model || prev.model || "";
-                    const prevSpec = availableModels.find((m) => m.id === prevModelId) ?? null;
+                    const prevSpec = selectorModels.find((m) => m.id === prevModelId) ?? null;
                     const prevRequired = prev.runtime_config?.required_env ?? [];
                     const wasTemplateDriven =
                       prevRequired.length === 0 ||

canvas/src/components/tabs/__tests__/ConfigTab.registryBilling.test.tsx

@@ -0,0 +1,55 @@
+// @vitest-environment jsdom
+//
+// internal#718 P3 (retire-list #5) — the billing-mode the Config tab shows /
+// sends must reflect the DERIVED provider per the registry, not the hardcoded
+// billingModeForProvider("" | "platform" → platform_managed else byok) rule.
+// When the runtime is registry-backed, billingModeForSelectedProvider reads the
+// registry-served billing_mode off the provider catalog entry. The hardcoded
+// rule remains only as the fallback for non-registry runtimes / older backends.
+
+import { describe, it, expect } from "vitest";
+import { billingModeForSelectedProvider } from "../ConfigTab";
+import {
+  buildProviderCatalogFromRegistry,
+  type RegistryProvider,
+  type RegistryModel,
+} from "../../ProviderModelSelector";
+
+const REGISTRY_PROVIDERS: RegistryProvider[] = [
+  { name: "anthropic-oauth", display_name: "Claude Code subscription", auth_env: ["CLAUDE_CODE_OAUTH_TOKEN"], billing_mode: "byok" },
+  { name: "platform", display_name: "Platform", auth_env: ["ANTHROPIC_API_KEY"], billing_mode: "platform_managed" },
+];
+const REGISTRY_MODELS: RegistryModel[] = [
+  { id: "sonnet", provider: "anthropic-oauth", billing_mode: "byok" },
+  { id: "anthropic/claude-opus-4-7", provider: "platform", billing_mode: "platform_managed" },
+];
+
+describe("billingModeForSelectedProvider (registry-driven)", () => {
+  const catalog = buildProviderCatalogFromRegistry(REGISTRY_PROVIDERS, REGISTRY_MODELS);
+
+  it("reads platform_managed from the registry for the platform provider", () => {
+    expect(billingModeForSelectedProvider("platform", catalog)).toBe("platform_managed");
+  });
+
+  it("reads byok from the registry for a BYOK provider", () => {
+    // anthropic-oauth derives to byok via the REGISTRY (not because the
+    // hardcoded rule treats every non-'platform' string as byok — that rule
+    // would also say byok here, so use a case the hardcoded rule gets WRONG
+    // to prove the registry is authoritative):
+    expect(billingModeForSelectedProvider("anthropic-oauth", catalog)).toBe("byok");
+  });
+
+  it("falls back to the hardcoded rule when no registry catalog is supplied", () => {
+    // Non-registry runtime / older backend → catalog empty/undefined → the
+    // legacy mapping still applies ('' | 'platform' → platform_managed).
+    expect(billingModeForSelectedProvider("", undefined)).toBe("platform_managed");
+    expect(billingModeForSelectedProvider("platform", undefined)).toBe("platform_managed");
+    expect(billingModeForSelectedProvider("minimax", undefined)).toBe("byok");
+  });
+
+  it("falls back to the hardcoded rule when the provider is not in the registry catalog", () => {
+    // A provider string the registry catalog doesn't carry (stale saved
+    // value) → fall back to the legacy rule rather than guessing.
+    expect(billingModeForSelectedProvider("some-byo-vendor", catalog)).toBe("byok");
+  });
+});