diff --git a/AGENTS.md b/AGENTS.md
index dc2791f..58b7691 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -26,7 +26,7 @@ proof-of-work/            ← the Next.js app (THIS is where you run npm)
   app/main/               ← authed UI; navigation.tsx = sidebar
   components/             ← React components (workouts/, ai/, settings/)
   lib/ai/                 ← AI subsystem (see below)
-  lib/ai/providers/       ← claude.ts openai.ts gemini.ts ollama.ts + index.ts (getProvider; openai.ts exports both openai + openai-compatible = 5 registered providers)
+  lib/ai/providers/       ← claude.ts openai.ts gemini.ts ollama.ts sparkcontrol.ts + index.ts (getProvider; openai.ts exports both openai + openai-compatible = 6 registered providers)
   prisma/schema.prisma    ← schema (mirror; real DB migrates via entrypoint ALTERs)
   prisma/*.seed.json      ← curated exercise library + AI templates (reconciled each boot)
   tests/                  ← Vitest specs (ai-*.test.ts, routes-*.test.ts, ...)
@@ -116,15 +116,15 @@ Canonical publish path for this project: `~/.proof-of-work/publish.sh` (builds,
 
 ## Current state
 
-Latest version is **1.2.0:6** — **AI "generate today's workout"**: describe one session in plain words → a streamed, ready-to-log workout (suggested weights/reps/set-counts grounded in 90-day history) → inline-edit or **Refine** (round-trips changes back to the LLM) → **Use this workout** pre-fills the New Workout form (nothing persists until you save). Reuses the program-generation spine via a new `AIGeneration.kind` discriminant (`"program" | "workout"`); workout rows are ephemeral (the saved Workout is the durable record) so they're filtered out of the program-shaped AI History. New `AIGeneration.kind` column (default "program") via boot-time guarded `ALTER`. **Architecture + hand-off (sessionStorage `?from=ai` → `AiWorkoutPrefill`, `EditWorkoutData.id?`→CREATE, per-exercise weight-unit grounding) are documented in `docs/guides/ai-subsystem.md` → "Two generation kinds".** **Built + sideloaded** (`immense-voyage.local`, 2026-06-19, `master`) as `proof-of-work_x86_64.s9pk` (80M). tsc clean (app + packaging), lint clean (pre-existing only), **251 tests pass**, `next build` + s9pk build succeed. Registry empty, **publishing parked** (sideload-only via `make install`).
+Latest version is **1.2.0:7** — **SparkControl AI provider + base-URL footgun fix**. Adds a 6th provider, **SparkControl (local)** — the operator's own self-hosted local-inference gateway. OpenAI-compatible wire format (reuses `generateOpenAIStyle`), **keyless** on the LAN (`requireApiKey:false` → no `Authorization` header), reached over the **internal same-box StartOS address** `http://spark-control.startos:9999/v1` (plain HTTP — no TLS, no cert-skip; the public LAN interface is HTTPS w/ a self-signed cert we deliberately avoid). The Settings form **auto-detects the loaded vLLM model** via SparkControl's `/api/endpoints` (`app/api/ai/sparkcontrol/model`, admin-only + SSRF-guarded), mirroring Ollama auto-detect; $0 in the cost UI. Also fixes a **config footgun** (origin of this session): a custom base URL could ride along to a fixed-URL provider (claude/openai/gemini) whose form field is hidden, get stored, and be **silently ignored** (the provider hits its hardcoded endpoint) — both config write paths (`configs` POST + `[id]` PATCH) now null `baseUrl` for non-custom-URL providers and the form clears it on provider change. **No schema/data change** (`AIConfigProfile.provider` is a free-text column). Details: `docs/guides/ai-subsystem.md` → Provider abstraction (incl. the new "adding a provider" fan-out checklist). **Built + sideloaded** (`immense-voyage.local`, 2026-06-19, `master`) as `proof-of-work_x86_64.s9pk` (80M). tsc clean (app + packaging), lint clean (pre-existing only), **259 tests pass**, `next build` + s9pk build succeed. Registry empty, **publishing parked** (sideload-only via `make install`).
 
 **Design contract established this session (2026-06-19, committed `7fda9ce`, no UI code changed):** the `design/` folder now holds the durable contract — `DESIGN.md` (9-section brief) + `tokens.tokens.json` (DTCG) + `brand/palette.css` + `inspiration/` provenance. From a Case-B *document-as-is* extract of the as-built dark UI: **monochrome gym-brutalist** (`#0A0A0A` canvas, zinc-only neutral, white primary button, Bebas-uppercase/tracked headings, flat border-based depth), plus two owner calls — **red elevated to the single brand accent `#DC2626`** and a **two-tier radius** (4px controls / 8px containers). AGENTS.md carries the read-before-UI Design line; `ROADMAP.md` → **Design** holds the `design-checker` cleanup backlog (gray→zinc, green→emerald, yellow→amber, `rounded-md`→`rounded`, overlay-only shadows, and a shared `<Button>`). **Read `design/DESIGN.md` before any UI work.**
 
-**Confirmed on-box (2026-06-19, via `start-cli`):** box runs `1.2.0:6`; entrypoint logged `adding AIGeneration.kind (default 'program')` once, then launched `as nextjs` with no errors (clears the long-standing non-root check); read-only `SELECT` confirms the `AIGeneration.kind` column exists and the existing generation row backfilled to `program`. Recent prior ships (1.2.0 line): **1.2.0:5** Gear replaces RPE for cardio; **1.2.0:4** watts as first-class set field; **1.2.0:3** P3 hardening (login timing oracle + `exerciseId` ownership).
+**Confirmed on-box (2026-06-19, via `start-cli`):** box runs `1.2.0:7`; launched `as nextjs` with no errors, "Ready in 221ms", and (correctly) **no migration ran** — this release adds no column. SparkControl itself is runtime-config (the operator must add a SparkControl config in Settings → AI to exercise it). Recent prior ships (1.2.0 line): **1.2.0:6** AI "today's workout"; **1.2.0:5** Gear replaces RPE for cardio; **1.2.0:4** watts as first-class set field.
 
-**No on-box checks pending.** Known bug (tracked in `ROADMAP.md` → Known bugs): the **1.2.0:2** Safari first-tap retry did NOT fix the mobile-Safari first-login failure — reproduced through 1.2.0:5 (the workout feature didn't touch auth), first tap shows "An unexpected error occurred", second tap works. Diagnosis captured; the fix is gated on one data point — the first failed request's error code from Safari Web Inspector (`-1005` → client delayed-retry; `502`/`503` → Node keep-alive tuning).
+**On-box follow-up (user action):** the live AI config is still the misconfigured one that triggered this session — `provider=gemini` with a LAN `baseUrl` the gemini provider ignores (so it silently hit Google's cloud and returned "Empty response"). The provider can't change on edit, so **delete that config and add a SparkControl one** (Settings → AI → Add config → SparkControl; URL auto-fills to `http://spark-control.startos:9999/v1`, model auto-detects, no key). Known bug (tracked in `ROADMAP.md` → Known bugs): the **1.2.0:2** Safari first-tap retry did NOT fix the mobile-Safari first-login failure — reproduced through 1.2.0:5 (the workout feature didn't touch auth), first tap shows "An unexpected error occurred", second tap works. Diagnosis captured; the fix is gated on one data point — the first failed request's error code from Safari Web Inspector (`-1005` → client delayed-retry; `502`/`503` → Node keep-alive tuning).
 
-Working: workout logging, programs (manual + AI), multi-user, curated library, full AI subsystem (5 providers, multi-config, background generation, **single-workout generation + refine**, history detail, cost/duration, Ollama auto-detect, infinite-scroll exercise history).
+Working: workout logging, programs (manual + AI), multi-user, curated library, full AI subsystem (6 providers incl. **SparkControl**, multi-config, background generation, single-workout generation + refine, history detail, cost/duration, Ollama + SparkControl auto-detect, infinite-scroll exercise history).
 
 Next steps (priority order):
 1. **Finish the P3 hardening batch** (`ROADMAP.md` → Security & hardening — timing oracle + exerciseId ownership now DONE): CSP `unsafe-eval`, `/api/health` info disclosure, rate-limit map leak, configurable/shorter sessions (currently 30-day), text max-length. Also unify the 3rd JSON-parse pattern (`try{json}catch{→{}}`) in `programs/[id]/days/[dayId]/start`.
diff --git a/docs/guides/ai-subsystem.md b/docs/guides/ai-subsystem.md
index e9c1272..53e17e7 100644
--- a/docs/guides/ai-subsystem.md
+++ b/docs/guides/ai-subsystem.md
@@ -47,11 +47,34 @@ stores the JSON in the (reused) `parsedProgram` column.
 
 - Each provider yields an async iterable of `GenerateChunk` (`text` / `usage` / `done` /
   `error`); add new ones under `lib/ai/providers/` and register in `index.ts`.
-  `openai.ts` exports both `openai` and `openai-compatible`, so the four provider files
-  register **5** providers (`claude`, `openai`, `openai-compatible`, `gemini`, `ollama`).
+  `openai.ts` exports both `openai` and `openai-compatible`, so the five provider files
+  register **6** providers (`claude`, `openai`, `openai-compatible`, `gemini`, `ollama`,
+  `sparkcontrol`).
+- **SparkControl** (`sparkcontrol.ts`) — the operator's own self-hosted local-inference
+  gateway. OpenAI-compatible wire format, so it reuses `generateOpenAIStyle` with
+  `{ requireApiKey: false }` (keyless on the LAN — the streamer omits the `Authorization`
+  header when no key is set). Reached over the **internal same-box StartOS address**
+  (`http://spark-control.startos:9999/v1`, plain HTTP — no TLS, no cert-skip). Custom base
+  URL ⇒ SSRF-guarded + admin-only, same as Ollama. The Settings UI auto-detects the loaded
+  vLLM model via `app/api/ai/sparkcontrol/model` (probes SparkControl's `/api/endpoints`
+  → `vllm.model`), mirroring the Ollama `/api/tags` auto-detect. Free in the cost UI.
+- **Base-URL hygiene:** only custom-URL providers (`requiresBaseUrl`: ollama,
+  openai-compatible, sparkcontrol) store a base URL. Both config write paths
+  (`configs` POST + `[id]` PATCH) null it for fixed-URL providers, and the Settings form
+  clears it on provider change — otherwise a stale URL silently rides along to
+  claude/openai/gemini, which ignore it and hit their hardcoded endpoints.
 - Streaming AI uses SSE; partial JSON is recovered with `lib/ai/lenientJson.ts`.
 - Pricing/model menus live in `lib/ai/pricing.ts` (`PRICES`, `MODEL_MENU`) — keep them
   paired so every menu model has a price entry (there's a test enforcing this).
+- **Adding a provider** (precedent: `sparkcontrol`, 1.2.0:7) is a fan-out across ~8 spots —
+  miss one and it half-works: the provider file + `ProviderId` union (`types.ts`) + register
+  in `providers/index.ts` (`ALL` + `PROVIDER_ORDER`); the zod `provider` enum in **both**
+  `configs` POST and `[id]` PATCH (+ `defaultName` PRETTY map); the UI `PROVIDERS` list in
+  `AIIntegration.tsx` (`requiresKey`/`requiresUrl` must mirror the server `requiresApiKey`/
+  `requiresBaseUrl`); `MODEL_MENU` (`[]` if no curated menu) + an `estimateCost` branch
+  (free/null for self-hosted). A custom-URL provider is admin-only + SSRF-guarded everywhere
+  (configs POST/PATCH, `ai/test`, any probe route) and must appear in those routes' 403
+  enumeration strings. `ai/test` and `generate` work for free once it's in `getProvider`.
 
 ## SSRF / provider-URL safety
 
diff --git a/proof-of-work/app/api/ai/configs/[id]/route.ts b/proof-of-work/app/api/ai/configs/[id]/route.ts
index dfcb801..6f097de 100644
--- a/proof-of-work/app/api/ai/configs/[id]/route.ts
+++ b/proof-of-work/app/api/ai/configs/[id]/route.ts
@@ -84,7 +84,7 @@ export async function PATCH(
     return NextResponse.json(
       {
         error:
-          'Only an admin can configure providers with a custom base URL (Ollama / OpenAI-compatible).',
+          'Only an admin can configure providers with a custom base URL (Ollama, SparkControl, OpenAI-compatible).',
       },
       { status: 403 },
     );
@@ -93,8 +93,13 @@ export async function PATCH(
   const data: Record<string, string | null> = {};
   if (parsed.data.name !== undefined) data.name = parsed.data.name;
   if (parsed.data.model !== undefined) data.model = parsed.data.model;
+  // Fixed-URL providers (claude/openai/gemini) ignore a base URL — never let an
+  // edit attach one (the footgun that produced a gemini config carrying a stale
+  // baseUrl). Provider can't change on PATCH, so `existing.provider` is authoritative.
   if (parsed.data.baseUrl !== undefined)
-    data.baseUrl = parsed.data.baseUrl || null;
+    data.baseUrl = isCustomUrlProvider(existing.provider)
+      ? parsed.data.baseUrl || null
+      : null;
   if (parsed.data.apiKey !== undefined)
     data.apiKey = parsed.data.apiKey || null;
 
diff --git a/proof-of-work/app/api/ai/configs/route.ts b/proof-of-work/app/api/ai/configs/route.ts
index 245d186..bc2be64 100644
--- a/proof-of-work/app/api/ai/configs/route.ts
+++ b/proof-of-work/app/api/ai/configs/route.ts
@@ -18,7 +18,14 @@ import { isCustomUrlProvider } from '@/lib/ai/providers';
  * [id]/activate/route.ts so the action is explicit + auditable.
  */
 
-const PROVIDERS = ['claude', 'openai', 'openai-compatible', 'gemini', 'ollama'] as const;
+const PROVIDERS = [
+  'claude',
+  'openai',
+  'openai-compatible',
+  'gemini',
+  'ollama',
+  'sparkcontrol',
+] as const;
 
 export async function GET() {
   const user = await getCurrentUser();
@@ -82,32 +89,44 @@ export async function POST(request: NextRequest) {
 
   const { name, provider, model, baseUrl, apiKey, setActive } = parsed.data;
 
-  // Custom-URL providers (Ollama / OpenAI-compatible) are admin-only — a
-  // non-admin pointing the server at an arbitrary URL is the SSRF actor
-  // vector. Fixed-URL cloud providers stay per-user.
+  // Custom-URL providers (Ollama, SparkControl, OpenAI-compatible) are
+  // admin-only — a non-admin pointing the server at an arbitrary URL is the
+  // SSRF actor vector. Fixed-URL cloud providers stay per-user.
   if (!user.isAdmin && (baseUrl || isCustomUrlProvider(provider))) {
     return NextResponse.json(
       {
         error:
-          'Only an admin can configure providers with a custom base URL (Ollama / OpenAI-compatible).',
+          'Only an admin can configure providers with a custom base URL (Ollama, SparkControl, OpenAI-compatible).',
       },
       { status: 403 },
     );
   }
 
+  // Only custom-URL providers (Ollama / OpenAI-compatible / SparkControl) carry
+  // a base URL. Fixed-URL providers (claude/openai/gemini) hit their hardcoded
+  // endpoint and ignore it — so we drop any stale baseUrl here rather than
+  // storing an impossible config (the footgun behind the gemini-with-a-baseURL
+  // mismatch). The UI also clears the field on provider change.
+  const normalizedBaseUrl = isCustomUrlProvider(provider) ? baseUrl || null : null;
+
   const profile = await prisma.aIConfigProfile.create({
     data: {
       userId: user.id,
       name: name ?? defaultName(provider, model),
       provider,
       model,
-      baseUrl: baseUrl || null,
+      baseUrl: normalizedBaseUrl,
       apiKey: apiKey || null,
     },
   });
 
   if (setActive) {
-    await activate(user.id, profile.id, { provider, model, baseUrl, apiKey });
+    await activate(user.id, profile.id, {
+      provider,
+      model,
+      baseUrl: normalizedBaseUrl,
+      apiKey,
+    });
   }
 
   return NextResponse.json({
@@ -128,6 +147,7 @@ function defaultName(provider: string, model: string): string {
     'openai-compatible': 'Custom',
     gemini: 'Gemini',
     ollama: 'Ollama',
+    sparkcontrol: 'SparkControl',
   };
   const label = PRETTY[provider] ?? provider;
   return `${label} · ${model}`;
diff --git a/proof-of-work/app/api/ai/sparkcontrol/model/route.ts b/proof-of-work/app/api/ai/sparkcontrol/model/route.ts
new file mode 100644
index 0000000..8fe4710
--- /dev/null
+++ b/proof-of-work/app/api/ai/sparkcontrol/model/route.ts
@@ -0,0 +1,109 @@
+import { NextRequest, NextResponse } from 'next/server';
+import { getCurrentUser } from '@/lib/auth';
+import { assertSafeProviderUrl } from '@/lib/ai/safeUrl';
+
+/**
+ * GET /api/ai/sparkcontrol/model?baseUrl=...
+ *
+ * Probes SparkControl's service-discovery endpoint (`/api/endpoints`) and
+ * returns the model vLLM currently has loaded, so the Settings UI can
+ * auto-fill the model field (the same role the Ollama /api/tags probe plays).
+ * When no baseUrl is given it walks the canonical same-box StartOS addresses
+ * and, on a hit, hands back a `baseUrl` (with the `/v1` chat suffix) the UI
+ * can pre-fill.
+ *
+ * `/api/endpoints` lives at the host root, NOT under `/v1` — so we strip a
+ * trailing `/v1` off the configured chat base URL before probing.
+ *
+ * Authenticated + admin-only: pointing the server at an arbitrary URL is the
+ * SSRF surface (same gate as the Ollama probe), and a non-admin shouldn't be
+ * able to fingerprint the local network.
+ *
+ * Response:
+ *   { ok: true,  baseUrl, model: string | null, ready: boolean | null, ms }
+ *   { ok: false, baseUrl, error, ms }
+ */
+
+const PROBE_TIMEOUT_MS = 5_000;
+
+// Canonical same-box addresses (StartOS 0.4 `.startos`, legacy 0.3 `.embassy`),
+// including the `/v1` chat suffix the config field expects.
+const DEFAULT_CANDIDATES = [
+  'http://spark-control.startos:9999/v1',
+  'http://spark-control.embassy:9999/v1',
+];
+
+export async function GET(request: NextRequest) {
+  const user = await getCurrentUser();
+  if (!user) return NextResponse.json({ ok: false, error: 'Unauthorized' }, { status: 401 });
+  // Custom-URL surface ⇒ admin-only (same as the Ollama probe).
+  if (!user.isAdmin)
+    return NextResponse.json({ ok: false, error: 'Forbidden' }, { status: 403 });
+
+  const url = new URL(request.url);
+  const explicit = url.searchParams.get('baseUrl');
+  const candidates = explicit ? [explicit] : DEFAULT_CANDIDATES;
+
+  for (const candidate of candidates) {
+    const result = await probe(candidate);
+    if (result.ok) return NextResponse.json(result);
+    // For an explicit URL, surface the failure right away.
+    if (explicit) return NextResponse.json(result);
+  }
+  return NextResponse.json({
+    ok: false,
+    baseUrl: candidates[0],
+    error: 'No SparkControl instance responded at the default StartOS addresses.',
+    ms: 0,
+  });
+}
+
+interface EndpointsResponse {
+  vllm?: { ready?: boolean; model?: string | null; disabled?: boolean };
+}
+
+async function probe(baseUrl: string) {
+  const t0 = Date.now();
+  let url: string;
+  try {
+    // `/api/endpoints` lives at the host root, independent of the `/v1` chat
+    // path — so probe the origin, not a string-derived prefix. (new URL also
+    // throws on a malformed baseUrl, which this catch turns into ok:false.)
+    url = new URL(baseUrl).origin + '/api/endpoints';
+    await assertSafeProviderUrl(url);
+  } catch (e) {
+    return { ok: false as const, baseUrl, error: (e as Error).message, ms: Date.now() - t0 };
+  }
+  const ctrl = new AbortController();
+  const timer = setTimeout(() => ctrl.abort(), PROBE_TIMEOUT_MS);
+  try {
+    const res = await fetch(url, { signal: ctrl.signal });
+    clearTimeout(timer);
+    if (!res.ok) {
+      return {
+        ok: false as const,
+        baseUrl,
+        error: `SparkControl returned HTTP ${res.status}`,
+        ms: Date.now() - t0,
+      };
+    }
+    const body = (await res.json()) as EndpointsResponse;
+    return {
+      ok: true as const,
+      baseUrl,
+      model: body.vllm?.model ?? null,
+      ready: body.vllm?.ready ?? null,
+      ms: Date.now() - t0,
+    };
+  } catch (e) {
+    clearTimeout(timer);
+    return {
+      ok: false as const,
+      baseUrl,
+      error: ctrl.signal.aborted
+        ? `Timed out after ${PROBE_TIMEOUT_MS / 1000}s`
+        : (e as Error).message,
+      ms: Date.now() - t0,
+    };
+  }
+}
diff --git a/proof-of-work/app/api/ai/test/route.ts b/proof-of-work/app/api/ai/test/route.ts
index 9f914a8..6108aaf 100644
--- a/proof-of-work/app/api/ai/test/route.ts
+++ b/proof-of-work/app/api/ai/test/route.ts
@@ -120,7 +120,7 @@ export async function POST(request: NextRequest) {
       {
         ok: false,
         error:
-          'Only an admin can test providers with a custom base URL (Ollama / OpenAI-compatible).',
+          'Only an admin can test providers with a custom base URL (Ollama, SparkControl, OpenAI-compatible).',
       },
       { status: 403 },
     );
diff --git a/proof-of-work/components/settings/AIIntegration.tsx b/proof-of-work/components/settings/AIIntegration.tsx
index 211258e..1006d30 100644
--- a/proof-of-work/components/settings/AIIntegration.tsx
+++ b/proof-of-work/components/settings/AIIntegration.tsx
@@ -29,6 +29,12 @@ const PROVIDERS = [
   },
   { id: 'gemini', label: 'Google Gemini', requiresKey: true, requiresUrl: false },
   { id: 'ollama', label: 'Ollama (self-hosted)', requiresKey: false, requiresUrl: true },
+  {
+    id: 'sparkcontrol',
+    label: 'SparkControl (local)',
+    requiresKey: false,
+    requiresUrl: true,
+  },
 ] as const;
 
 type ProviderId = (typeof PROVIDERS)[number]['id'];
@@ -382,6 +388,11 @@ function ConfigForm({ initial, isAdmin, onCancel, onCreated }: ConfigFormProps)
   const [ollamaProbing, setOllamaProbing] = useState(false);
   const [ollamaProbeError, setOllamaProbeError] = useState<string | null>(null);
 
+  // SparkControl auto-detect (the currently-loaded vLLM model via /api/endpoints).
+  const [sparkModel, setSparkModel] = useState<string | null>(null);
+  const [sparkProbing, setSparkProbing] = useState(false);
+  const [sparkProbeError, setSparkProbeError] = useState<string | null>(null);
+
   const meta = PROVIDERS.find((p) => p.id === provider);
 
   // Probe Ollama on provider switch (or baseUrl change while ollama).
@@ -427,6 +438,48 @@ function ConfigForm({ initial, isAdmin, onCancel, onCreated }: ConfigFormProps)
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [provider, baseUrl]);
 
+  // Probe SparkControl on provider switch (or baseUrl change while selected):
+  // pre-fill the canonical same-box URL and the loaded model name.
+  useEffect(() => {
+    if (provider !== 'sparkcontrol') {
+      setSparkModel(null);
+      setSparkProbeError(null);
+      return;
+    }
+    let cancelled = false;
+    setSparkProbing(true);
+    setSparkProbeError(null);
+    const url = baseUrl
+      ? `/api/ai/sparkcontrol/model?baseUrl=${encodeURIComponent(baseUrl)}`
+      : '/api/ai/sparkcontrol/model';
+    fetch(url)
+      .then((r) => r.json())
+      .then((b) => {
+        if (cancelled) return;
+        if (b.ok) {
+          setSparkModel(b.model ?? null);
+          setSparkProbeError(null);
+          // Pre-fill the URL (with /v1) if the user hadn't typed one yet.
+          if (!baseUrl && b.baseUrl) setBaseUrl(b.baseUrl);
+          // Pre-pick the loaded model in create mode if the field is empty.
+          if (!isEdit && !model && b.model) setModel(b.model);
+        } else {
+          setSparkModel(null);
+          setSparkProbeError(b.error ?? 'Probe failed');
+        }
+      })
+      .catch((e) => {
+        if (!cancelled) setSparkProbeError((e as Error).message);
+      })
+      .finally(() => {
+        if (!cancelled) setSparkProbing(false);
+      });
+    return () => {
+      cancelled = true;
+    };
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [provider, baseUrl]);
+
   // Reset draft test result whenever the user changes any input — so the
   // green "✓ Connected" indicator never lingers from a previous attempt.
   useEffect(() => {
@@ -511,6 +564,9 @@ function ConfigForm({ initial, isAdmin, onCancel, onCreated }: ConfigFormProps)
             setProvider(e.target.value as ProviderId);
             setModel(''); // reset on provider change
             setModelMode('menu');
+            // Clear any URL typed for a previous (custom-URL) provider so it
+            // can't ride along to a fixed-URL provider whose field is hidden.
+            setBaseUrl('');
           }}
           className={inputClass}
           disabled={isEdit}
@@ -570,6 +626,30 @@ function ConfigForm({ initial, isAdmin, onCancel, onCreated }: ConfigFormProps)
             />
           )}
         </Field>
+      ) : provider === 'sparkcontrol' ? (
+        <Field
+          label={
+            <>
+              Model{' '}
+              {sparkProbing ? (
+                <span className="text-zinc-500 normal-case font-normal">· detecting…</span>
+              ) : sparkModel ? (
+                <span className="text-emerald-400 normal-case font-normal">· detected</span>
+              ) : sparkProbeError ? (
+                <span className="text-amber-400 normal-case font-normal">
+                  · could not reach SparkControl (type a name)
+                </span>
+              ) : null}
+            </>
+          }
+        >
+          <input
+            value={model}
+            onChange={(e) => setModel(e.target.value)}
+            placeholder={sparkModel ?? 'auto-detected from SparkControl'}
+            className={inputClass}
+          />
+        </Field>
       ) : showMenu ? (
         <Field label="Model">
           <select
@@ -628,7 +708,9 @@ function ConfigForm({ initial, isAdmin, onCancel, onCreated }: ConfigFormProps)
             placeholder={
               meta.id === 'ollama'
                 ? 'http://ollama.startos:11434'
-                : 'https://your-gateway.example.com/v1'
+                : meta.id === 'sparkcontrol'
+                  ? 'http://spark-control.startos:9999/v1'
+                  : 'https://your-gateway.example.com/v1'
             }
             className={inputClass}
           />
diff --git a/proof-of-work/lib/ai/pricing.ts b/proof-of-work/lib/ai/pricing.ts
index 1027e31..c0643d4 100644
--- a/proof-of-work/lib/ai/pricing.ts
+++ b/proof-of-work/lib/ai/pricing.ts
@@ -123,10 +123,12 @@ export const MODEL_MENU: Record<string, ModelOption[]> = {
     { id: 'gemini-2.5-flash', label: 'Gemini 2.5 Flash' },
     { id: 'gemini-2.0-flash', label: 'Gemini 2.0 Flash (legacy)' },
   ],
-  // openai-compatible + ollama: no curated menu — model names are
-  // gateway- or host-specific. Ollama auto-detects via /api/tags.
+  // openai-compatible + ollama + sparkcontrol: no curated menu — model names
+  // are gateway- or host-specific. Ollama auto-detects via /api/tags;
+  // SparkControl auto-detects the loaded model via /api/endpoints.
   'openai-compatible': [],
   ollama: [],
+  sparkcontrol: [],
 };
 
 /** Find the price entry whose key is a (case-insensitive) prefix of the model string. */
@@ -153,6 +155,7 @@ export function estimateCost(opts: {
   tokensOut: number | null;
 }): number | null {
   if (opts.provider === 'ollama') return 0; // self-hosted, no per-token cost
+  if (opts.provider === 'sparkcontrol') return 0; // self-hosted local inference, free
   if (opts.provider === 'openai-compatible') return null; // we don't know the gateway's pricing
   if (opts.tokensIn == null || opts.tokensOut == null) return null;
   const price = findPrice(opts.model);
diff --git a/proof-of-work/lib/ai/providers/index.ts b/proof-of-work/lib/ai/providers/index.ts
index 8d4818b..f3e18dc 100644
--- a/proof-of-work/lib/ai/providers/index.ts
+++ b/proof-of-work/lib/ai/providers/index.ts
@@ -3,6 +3,7 @@ import { ollama } from './ollama';
 import { claude } from './claude';
 import { openai, openaiCompatible } from './openai';
 import { gemini } from './gemini';
+import { sparkcontrol } from './sparkcontrol';
 
 const ALL: Record<ProviderId, LLMProvider> = {
   claude,
@@ -10,6 +11,7 @@ const ALL: Record<ProviderId, LLMProvider> = {
   'openai-compatible': openaiCompatible,
   gemini,
   ollama,
+  sparkcontrol,
 };
 
 export function getProvider(id: string): LLMProvider | null {
@@ -17,10 +19,10 @@ export function getProvider(id: string): LLMProvider | null {
 }
 
 /**
- * True for providers that take a user-supplied base URL (Ollama,
+ * True for providers that take a user-supplied base URL (Ollama, SparkControl,
  * OpenAI-compatible). Configuring these is admin-only — a non-admin pointing
- * the server at an arbitrary URL is the SSRF actor vector (EVALUATION.md P1).
- * The fixed-URL cloud providers (claude/openai/gemini) stay per-user.
+ * the server at an arbitrary URL is the SSRF actor vector. The fixed-URL cloud
+ * providers (claude/openai/gemini) stay per-user.
  */
 export function isCustomUrlProvider(id: string): boolean {
   return !!getProvider(id)?.requiresBaseUrl;
@@ -33,6 +35,7 @@ export const PROVIDER_ORDER: ProviderId[] = [
   'openai-compatible',
   'gemini',
   'ollama',
+  'sparkcontrol',
 ];
 
 export const PROVIDERS = ALL;
diff --git a/proof-of-work/lib/ai/providers/openai.ts b/proof-of-work/lib/ai/providers/openai.ts
index 5fbd05a..559cf1b 100644
--- a/proof-of-work/lib/ai/providers/openai.ts
+++ b/proof-of-work/lib/ai/providers/openai.ts
@@ -17,8 +17,9 @@ export async function* generateOpenAIStyle(
   opts: GenerateOpts,
   baseUrl: string,
   providerLabel: string,
+  { requireApiKey = true }: { requireApiKey?: boolean } = {},
 ): AsyncGenerator<GenerateChunk, void, void> {
-  if (!opts.apiKey) {
+  if (requireApiKey && !opts.apiKey) {
     yield { type: 'error', message: `${providerLabel} API key is required.` };
     return;
   }
@@ -29,7 +30,10 @@ export async function* generateOpenAIStyle(
       method: 'POST',
       headers: {
         'content-type': 'application/json',
-        authorization: `Bearer ${opts.apiKey}`,
+        // Only send Authorization when we actually have a key. SparkControl
+        // and other keyless LAN gateways take no auth; an empty Bearer would
+        // be wrong (and some servers reject it).
+        ...(opts.apiKey ? { authorization: `Bearer ${opts.apiKey}` } : {}),
       },
       body: JSON.stringify({
         model: opts.model,
diff --git a/proof-of-work/lib/ai/providers/sparkcontrol.ts b/proof-of-work/lib/ai/providers/sparkcontrol.ts
new file mode 100644
index 0000000..1f00190
--- /dev/null
+++ b/proof-of-work/lib/ai/providers/sparkcontrol.ts
@@ -0,0 +1,50 @@
+import type { LLMProvider } from '../types';
+import { generateOpenAIStyle } from './openai';
+import { assertSafeProviderUrl } from '../safeUrl';
+
+/**
+ * SparkControl — a self-hosted local-inference gateway (the operator's own
+ * StartOS package). Its LLM surface is OpenAI-compatible
+ * (`POST {baseUrl}/chat/completions`, SSE `data:` frames, `[DONE]`), so we
+ * reuse the OpenAI-style streamer wholesale.
+ *
+ * Two differences from the generic `openai-compatible` provider:
+ *   1. **No API key.** SparkControl takes no auth on the LAN, so the key is
+ *      optional (`requireApiKey: false`) — the streamer omits the
+ *      Authorization header when none is set.
+ *   2. **Reached over the internal same-box address** (e.g.
+ *      `http://spark-control.startos:9999/v1`) — plain HTTP, no TLS to worry
+ *      about. The public LAN interface is HTTPS with a self-signed Start9
+ *      cert; we deliberately don't go there, so no cert-verification games.
+ *
+ * Custom base URL ⇒ SSRF-guarded + admin-only, same as Ollama. The model name
+ * is whatever vLLM currently has loaded; the Settings UI auto-detects it via
+ * SparkControl's `/api/endpoints` discovery (see app/api/ai/sparkcontrol/model).
+ */
+export const sparkcontrol: LLMProvider = {
+  id: 'sparkcontrol',
+  label: 'SparkControl (local)',
+  requiresApiKey: false,
+  requiresBaseUrl: true,
+  async *generate(opts) {
+    if (!opts.baseUrl) {
+      yield {
+        type: 'error',
+        message:
+          'Base URL is required (e.g. http://spark-control.startos:9999/v1).',
+      };
+      return;
+    }
+    // User-supplied base URL → SSRF guard (private-LAN + loopback allowed on
+    // purpose; reaching spark-control.startos is the feature).
+    try {
+      await assertSafeProviderUrl(opts.baseUrl);
+    } catch (e) {
+      yield { type: 'error', message: `SparkControl: ${(e as Error).message}` };
+      return;
+    }
+    yield* generateOpenAIStyle(opts, opts.baseUrl, 'SparkControl', {
+      requireApiKey: false,
+    });
+  },
+};
diff --git a/proof-of-work/lib/ai/types.ts b/proof-of-work/lib/ai/types.ts
index aea58b1..5879c26 100644
--- a/proof-of-work/lib/ai/types.ts
+++ b/proof-of-work/lib/ai/types.ts
@@ -20,7 +20,8 @@ export type ProviderId =
   | 'openai'
   | 'openai-compatible'
   | 'gemini'
-  | 'ollama';
+  | 'ollama'
+  | 'sparkcontrol';
 
 export interface GenerateOpts {
   /** API key. Null/undefined for ollama on a trusted LAN. */
diff --git a/proof-of-work/tests/ai-sparkcontrol.test.ts b/proof-of-work/tests/ai-sparkcontrol.test.ts
new file mode 100644
index 0000000..30200bb
--- /dev/null
+++ b/proof-of-work/tests/ai-sparkcontrol.test.ts
@@ -0,0 +1,99 @@
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { sparkcontrol } from '@/lib/ai/providers/sparkcontrol';
+import type { GenerateChunk } from '@/lib/ai/types';
+
+/**
+ * SparkControl provider: OpenAI-style streaming over the internal same-box
+ * URL, with NO API key (and therefore no Authorization header).
+ */
+
+function sse(frames: string[]): string {
+  return frames.map((f) => `data: ${f}\n\n`).join('');
+}
+
+async function collect(
+  gen: AsyncIterable<GenerateChunk>,
+): Promise<GenerateChunk[]> {
+  const out: GenerateChunk[] = [];
+  for await (const c of gen) out.push(c);
+  return out;
+}
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+});
+
+describe('sparkcontrol provider', () => {
+  it('errors when no base URL is configured', async () => {
+    const chunks = await collect(
+      sparkcontrol.generate({
+        model: 'whatever',
+        systemPrompt: 'sys',
+        userPrompt: 'hi',
+      }),
+    );
+    expect(chunks[0]).toEqual({
+      type: 'error',
+      message: expect.stringContaining('Base URL is required'),
+    });
+  });
+
+  it('streams deltas + usage and sends NO Authorization header (keyless)', async () => {
+    const fetchMock = vi.fn(
+      // Typed params so mock.calls[0] is a [url, init] tuple, not [].
+      async (_url: string, _init: RequestInit) =>
+        new Response(
+          sse([
+            '{"choices":[{"delta":{"content":"Hello"}}]}',
+            '{"choices":[{"delta":{"content":" there"}}]}',
+            '{"usage":{"prompt_tokens":5,"completion_tokens":2}}',
+            '[DONE]',
+          ]),
+          { status: 200, headers: { 'content-type': 'text/event-stream' } },
+        ),
+    );
+    vi.stubGlobal('fetch', fetchMock);
+
+    const chunks = await collect(
+      sparkcontrol.generate({
+        // Loopback literal → passes the SSRF guard without DNS.
+        baseUrl: 'http://127.0.0.1:9999/v1',
+        model: 'RedHatAI/Qwen3.6-35B-A3B-NVFP4',
+        systemPrompt: 'sys',
+        userPrompt: 'hi',
+      }),
+    );
+
+    // POSTs to {baseUrl}/chat/completions.
+    expect(fetchMock).toHaveBeenCalledTimes(1);
+    const [url, init] = fetchMock.mock.calls[0];
+    expect(url).toBe('http://127.0.0.1:9999/v1/chat/completions');
+
+    // Keyless: no Authorization header at all.
+    const headers = init.headers as Record<string, string>;
+    expect('authorization' in headers).toBe(false);
+    expect(headers.authorization).toBeUndefined();
+
+    // Streamed text + usage made it through.
+    const text = chunks
+      .filter((c): c is Extract<GenerateChunk, { type: 'text' }> => c.type === 'text')
+      .map((c) => c.delta)
+      .join('');
+    expect(text).toBe('Hello there');
+    expect(chunks).toContainEqual({ type: 'usage', tokensIn: 5, tokensOut: 2 });
+    expect(chunks.some((c) => c.type === 'done')).toBe(true);
+  });
+
+  it('blocks an SSRF-unsafe base URL (cloud metadata)', async () => {
+    const chunks = await collect(
+      sparkcontrol.generate({
+        baseUrl: 'http://169.254.169.254/v1',
+        model: 'x',
+        systemPrompt: 'sys',
+        userPrompt: 'hi',
+      }),
+    );
+    expect(chunks[0].type).toBe('error');
+    expect((chunks[0] as { message: string }).message).toContain('SparkControl');
+  });
+});
diff --git a/proof-of-work/tests/routes-ai-configs.test.ts b/proof-of-work/tests/routes-ai-configs.test.ts
new file mode 100644
index 0000000..e3444e7
--- /dev/null
+++ b/proof-of-work/tests/routes-ai-configs.test.ts
@@ -0,0 +1,170 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+
+const { getCurrentUserMock } = vi.hoisted(() => ({
+  getCurrentUserMock: vi.fn(),
+}));
+vi.mock('@/lib/auth', async (orig) => {
+  const actual = (await orig()) as Record<string, unknown>;
+  return { ...actual, getCurrentUser: getCurrentUserMock };
+});
+
+import { NextRequest } from 'next/server';
+import { prisma } from '@/lib/prisma';
+import { POST as createConfig } from '@/app/api/ai/configs/route';
+import { PATCH as patchConfig } from '@/app/api/ai/configs/[id]/route';
+
+/**
+ * Base-URL hygiene on AI config writes:
+ *  - Fixed-URL providers (claude/openai/gemini) must NEVER store a base URL,
+ *    even if one rides along in the body (the footgun that produced a gemini
+ *    config silently pointed at a custom URL the gemini provider ignores).
+ *  - Custom-URL providers (incl. SparkControl) keep it. SparkControl also
+ *    needs no API key.
+ */
+
+function jsonReq(url: string, body: unknown, method = 'POST'): NextRequest {
+  return new NextRequest(url, {
+    method,
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify(body),
+  } as ConstructorParameters<typeof NextRequest>[1]);
+}
+
+async function makeAdmin(email: string) {
+  return prisma.user.create({
+    data: { email, passwordHash: 'fake', isAdmin: true },
+  });
+}
+
+beforeEach(async () => {
+  await prisma.aIConfigProfile.deleteMany();
+  await prisma.userPreferences.deleteMany();
+  await prisma.user.deleteMany();
+  getCurrentUserMock.mockReset();
+});
+
+describe('POST /api/ai/configs — base-URL hygiene', () => {
+  it('drops a base URL on a fixed-URL provider (gemini) and its active mirror', async () => {
+    const u = await makeAdmin('a@x.com');
+    getCurrentUserMock.mockResolvedValue(u);
+
+    const res = await createConfig(
+      jsonReq('http://x/api/ai/configs', {
+        provider: 'gemini',
+        model: 'gemini-2.5-flash',
+        baseUrl: 'http://192.168.1.72:62419/v1',
+        apiKey: 'sk-real',
+        setActive: true,
+      }),
+    );
+    expect(res.status).toBe(200);
+    const body = await res.json();
+    expect(body.baseUrl).toBeNull();
+
+    const profile = await prisma.aIConfigProfile.findFirstOrThrow({
+      where: { userId: u.id },
+    });
+    expect(profile.baseUrl).toBeNull();
+
+    // The legacy mirror in UserPreferences must also be clean.
+    const prefs = await prisma.userPreferences.findUnique({ where: { userId: u.id } });
+    expect(prefs?.aiBaseUrl).toBeNull();
+  });
+
+  it('keeps the base URL for SparkControl and needs no API key', async () => {
+    const u = await makeAdmin('b@x.com');
+    getCurrentUserMock.mockResolvedValue(u);
+
+    const res = await createConfig(
+      jsonReq('http://x/api/ai/configs', {
+        provider: 'sparkcontrol',
+        model: 'RedHatAI/Qwen3.6-35B-A3B-NVFP4',
+        baseUrl: 'http://spark-control.startos:9999/v1',
+        setActive: true,
+      }),
+    );
+    expect(res.status).toBe(200);
+    const body = await res.json();
+    expect(body.baseUrl).toBe('http://spark-control.startos:9999/v1');
+    expect(body.keyConfigured).toBe(false);
+
+    const profile = await prisma.aIConfigProfile.findFirstOrThrow({
+      where: { userId: u.id },
+    });
+    expect(profile.baseUrl).toBe('http://spark-control.startos:9999/v1');
+    expect(profile.apiKey).toBeNull();
+
+    const prefs = await prisma.userPreferences.findUnique({ where: { userId: u.id } });
+    expect(prefs?.aiBaseUrl).toBe('http://spark-control.startos:9999/v1');
+  });
+
+  it('rejects a non-admin creating a SparkControl config and names it in the error', async () => {
+    const u = await prisma.user.create({
+      data: { email: 'nonadmin@x.com', passwordHash: 'fake', isAdmin: false },
+    });
+    getCurrentUserMock.mockResolvedValue(u);
+
+    const res = await createConfig(
+      jsonReq('http://x/api/ai/configs', {
+        provider: 'sparkcontrol',
+        model: 'some-model',
+        baseUrl: 'http://spark-control.startos:9999/v1',
+      }),
+    );
+    expect(res.status).toBe(403);
+    const body = await res.json();
+    expect(body.error).toContain('SparkControl');
+  });
+});
+
+describe('PATCH /api/ai/configs/[id] — base-URL hygiene', () => {
+  it('refuses to attach a base URL to a fixed-URL provider on edit', async () => {
+    const u = await makeAdmin('c@x.com');
+    getCurrentUserMock.mockResolvedValue(u);
+
+    const created = await prisma.aIConfigProfile.create({
+      data: { userId: u.id, name: 'g', provider: 'gemini', model: 'gemini-2.5-flash' },
+    });
+
+    const res = await patchConfig(
+      jsonReq(`http://x/api/ai/configs/${created.id}`, {
+        baseUrl: 'http://192.168.1.72:62419/v1',
+      }, 'PATCH'),
+      { params: Promise.resolve({ id: created.id }) },
+    );
+    expect(res.status).toBe(200);
+
+    const after = await prisma.aIConfigProfile.findFirstOrThrow({ where: { id: created.id } });
+    expect(after.baseUrl).toBeNull();
+  });
+
+  it('cleans the active-config mirror when stripping a base URL on edit', async () => {
+    const u = await makeAdmin('d@x.com');
+    getCurrentUserMock.mockResolvedValue(u);
+
+    // Create + activate a gemini config (mirrors into UserPreferences).
+    const createRes = await createConfig(
+      jsonReq('http://x/api/ai/configs', {
+        provider: 'gemini',
+        model: 'gemini-2.5-flash',
+        apiKey: 'sk-real',
+        setActive: true,
+      }),
+    );
+    const { id } = await createRes.json();
+
+    const res = await patchConfig(
+      jsonReq(`http://x/api/ai/configs/${id}`, {
+        baseUrl: 'http://192.168.1.72:62419/v1',
+      }, 'PATCH'),
+      { params: Promise.resolve({ id }) },
+    );
+    expect(res.status).toBe(200);
+
+    const after = await prisma.aIConfigProfile.findFirstOrThrow({ where: { id } });
+    expect(after.baseUrl).toBeNull();
+    // The active mirror in UserPreferences must be clean too.
+    const prefs = await prisma.userPreferences.findUnique({ where: { userId: u.id } });
+    expect(prefs?.aiBaseUrl).toBeNull();
+  });
+});
diff --git a/start9/0.4/startos/versions/index.ts b/start9/0.4/startos/versions/index.ts
index 5c1c513..e5d4874 100644
--- a/start9/0.4/startos/versions/index.ts
+++ b/start9/0.4/startos/versions/index.ts
@@ -21,6 +21,7 @@ import { v_1_2_0_3 } from './v1.2.0.3'
 import { v_1_2_0_4 } from './v1.2.0.4'
 import { v_1_2_0_5 } from './v1.2.0.5'
 import { v_1_2_0_6 } from './v1.2.0.6'
+import { v_1_2_0_7 } from './v1.2.0.7'
 
 /**
  * Version graph for the `proof-of-work` package.
@@ -86,9 +87,13 @@ import { v_1_2_0_6 } from './v1.2.0.6'
  *            inline-edit + refine-with-AI, then pre-fill the workout log.
  *            Reuses the generation spine via a new AIGeneration.kind
  *            discriminant (boot ALTER, default "program"). No data changes.
+ * v1.2.0:7 — SparkControl AI provider (6th provider): keyless, same-box
+ *            internal address, model auto-detected via /api/endpoints. Plus a
+ *            base-URL footgun fix (a custom URL could attach to a fixed-URL
+ *            provider and be silently ignored). No schema/data change.
  */
 export const versionGraph = VersionGraph.of({
-  current: v_1_2_0_6,
+  current: v_1_2_0_7,
   other: [
     v_1_0_0_1,
     v_1_0_0_2,
@@ -111,5 +116,6 @@ export const versionGraph = VersionGraph.of({
     v_1_2_0_3,
     v_1_2_0_4,
     v_1_2_0_5,
+    v_1_2_0_6,
   ],
 })
diff --git a/start9/0.4/startos/versions/v1.2.0.7.ts b/start9/0.4/startos/versions/v1.2.0.7.ts
new file mode 100644
index 0000000..b10cc11
--- /dev/null
+++ b/start9/0.4/startos/versions/v1.2.0.7.ts
@@ -0,0 +1,33 @@
+import { IMPOSSIBLE, VersionInfo } from '@start9labs/start-sdk'
+
+/**
+ * v1.2.0:7 — SparkControl AI provider + base-URL footgun fix (2026-06-19).
+ *
+ * Adds a 6th AI provider, "SparkControl (local)" — the operator's own
+ * self-hosted local-inference gateway. Its LLM surface is OpenAI-compatible,
+ * so it reuses the OpenAI-style streamer, with two twists: no API key (keyless
+ * on the LAN) and reached over the internal same-box StartOS address
+ * (http://spark-control.startos:9999/v1, plain HTTP — no TLS games). The
+ * Settings UI auto-detects the loaded vLLM model via SparkControl's
+ * /api/endpoints discovery, mirroring the Ollama auto-detect.
+ *
+ * Also fixes a config footgun: a base URL could ride along to a fixed-URL
+ * provider (Claude/OpenAI/Gemini) whose form field is hidden — stored but
+ * silently ignored by the provider, which always hits its hardcoded endpoint.
+ * Both config write paths now drop a base URL for non-custom-URL providers,
+ * and the form clears it on provider change.
+ *
+ * No schema or data change: `AIConfigProfile.provider` is a free-text column,
+ * so the new value needs no migration. Existing configs are untouched.
+ */
+export const v_1_2_0_7 = VersionInfo.of({
+  version: '1.2.0:7',
+  releaseNotes: {
+    en_US:
+      'New AI provider: SparkControl — your self-hosted local-inference gateway. Reached over the same-box address with no API key; the model is auto-detected. Also fixes a bug where a custom base URL could attach to a fixed-URL provider (Claude/OpenAI/Gemini) and be silently ignored. No data changes.',
+  },
+  migrations: {
+    up: async () => {},
+    down: IMPOSSIBLE,
+  },
+})