chore: bump action to 0.1.5

max effort burns roughly 2x the wall time per turn for marginal quality
gain. high is the model's tuned default ('equivalent to not setting the
parameter' per Anthropic docs). full-send can be reintroduced as an
opt-in per-run override later if needed.

agents/claude.ts

@@ -90,10 +90,13 @@ function stripProviderPrefix(specifier: string): string {
   return slashIndex > 0 ? specifier.slice(slashIndex + 1) : specifier;
 }
 
-// `max` effort is supported on Opus 4.6 / 4.7; other models fall back to `high`.
-// claude-code deny-lists older opus/sonnet generations from `max` at invocation time.
-function resolveEffort(model: string | undefined): "max" | "high" {
-  if (model?.includes("opus")) return "max";
+// `high` is the model's tuned default ("equivalent to not setting the parameter"
+// per Anthropic docs). `max` is "absolute maximum capability with no constraints
+// on token spending" — meaningfully slower and burns more thinking budget per
+// turn. We default everyone to `high`; PRs that genuinely need full-send can
+// opt in via a future per-run override rather than paying the wall-time cost on
+// every Opus run.
+function resolveEffort(_model: string | undefined): "high" {
   return "high";
 }
 

main.ts

@@ -183,8 +183,9 @@ function billingConsoleUrl(owner: string, anchor: "billing" | "model-access"): s
  *
  * Branches:
  *   - `router_requires_card`: user is on Router mode with no card AND no
- *     wallet balance. Lead with the carrot ($20 free credit), link to
- *     `#model-access` where the Add Card flow lives.
+ *     wallet balance (signup credit exhausted or not granted). Frame as
+ *     "add a card to continue", link to `#model-access` where the Add
+ *     Card flow lives.
  *   - `router_balance_exhausted`: user has a card on file but auto-reload is
  *     disabled and they've spent past their $5 overdraft buffer. Frame as
  *     "balance ran out" and surface both remediation paths (top up, or flip
@@ -206,7 +207,7 @@ function formatBillingErrorSummary(error: BillingError, owner: string): string {
     return [
       "**Add a card to start using Pullfrog Router.**",
       "",
-      "Router proxies OpenRouter at raw cost — no platform markup, and your first $20 of usage is on us.",
+      "Router proxies OpenRouter at raw cost — no platform markup. Add a card and we'll auto-reload your wallet so runs keep flowing.",
       "",
       `[Add a card →](${billingConsoleUrl(owner, "model-access")})`,
     ].join("\n");
@@ -471,12 +472,16 @@ async function persistLearnings(ctx: ToolContext): Promise<void> {
     });
     if (!response.ok) {
       const error = await response.text().catch(() => "(no body)");
-      log.debug(`learnings persist failed (${response.status}): ${error}`);
+      // promoted from debug → warning: this path means the agent edited the
+      // file (we already short-circuited the unchanged-from-seed case above)
+      // but the PATCH dropped it on the floor. silently losing real work is
+      // worse than the noise of a CI warning.
+      log.warning(`learnings persist failed (${response.status}): ${error}`);
       return;
     }
     log.info("» learnings updated");
   } catch (err) {
-    log.debug(`learnings persist failed: ${err instanceof Error ? err.message : String(err)}`);
+    log.warning(`learnings persist failed: ${err instanceof Error ? err.message : String(err)}`);
   }
 }
 

mcp/geminiSanitizer.ts

@@ -176,13 +176,32 @@ export function sanitizeToolForGemini<T extends Tool<any, any>>(tool: T): T {
 }
 
 /**
- * true when the effective upstream model is served by google's generative
- * language API — directly (`google/*`), via opencode (`opencode/gemini-*`),
- * or via openrouter (`openrouter/google/gemini-*`). slug-substring match
- * works because every gemini route's model id contains "gemini".
+ * true when the effective upstream model is — or might become — google
+ * generative language API traffic. matches:
+ *   - direct `google/*`, opencode `opencode/gemini-*`, openrouter
+ *     `openrouter/google/gemini-*` (slug substring "gemini" wins).
+ *   - any unresolved specifier: `undefined`, `"auto"`, or a slug that
+ *     didn't map through the alias registry (no `provider/` prefix).
+ *     these flow through the agent's own auto-select, which may land
+ *     on gemini *after* the MCP server has already registered tools —
+ *     at which point sanitization is too late to apply. erring on the
+ *     side of sanitizing is safe: cases 1 + 2 are universally
+ *     compatible JSON-Schema normalizations (enum-only → typed string,
+ *     collapsible const-unions → string enum); case 3 is gemini-
+ *     specific but only fires on non-collapsible unions, which arktype
+ *     does not emit for our current tool schemas. see issue #676 for
+ *     the prod failure that motivated this widening.
  */
 export function isGeminiRouted(ctx: ToolContext): boolean {
   const effective = ctx.payload.proxyModel ?? ctx.resolvedModel ?? ctx.payload.model;
-  if (!effective) return false;
-  return effective.toLowerCase().includes("gemini");
+  if (!effective) return true;
+  const normalized = effective.toLowerCase();
+  if (normalized.includes("gemini")) return true;
+  // every concrete model resolved through the registry carries a
+  // `provider/` prefix (e.g. "anthropic/claude-opus-4-7"). anything
+  // without a slash is either the literal `"auto"` alias or an
+  // unrecognized slug that resolveModel logged a warning for — both
+  // route through the agent's late auto-select, which may pick gemini.
+  if (!normalized.includes("/")) return true;
+  return false;
 }

models.test.ts

@@ -55,13 +55,13 @@ describe("getModelEnvVars", () => {
 
   it("returns empty env vars for free opencode models", () => {
     expect(getModelEnvVars("opencode/big-pickle")).toEqual([]);
-    expect(getModelEnvVars("opencode/gpt-5-nano")).toEqual([]);
     expect(getModelEnvVars("opencode/mimo-v2-pro-free")).toEqual([]);
     expect(getModelEnvVars("opencode/minimax-m2.5-free")).toEqual([]);
   });
 
   it("still requires OPENCODE_API_KEY for non-free opencode models", () => {
     expect(getModelEnvVars("opencode/claude-opus")).toEqual(["OPENCODE_API_KEY"]);
+    expect(getModelEnvVars("opencode/gpt-5-nano")).toEqual(["OPENCODE_API_KEY"]);
   });
 });
 

models.ts

@@ -271,8 +271,7 @@ export const providers = {
       "gpt-5-nano": {
         displayName: "GPT Nano",
         resolve: "opencode/gpt-5-nano",
-        envVars: [],
-        isFree: true,
+        openRouterResolve: "openrouter/openai/gpt-5-nano",
       },
       "mimo-v2-pro-free": {
         displayName: "MiMo V2 Pro",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "pullfrog",
-  "version": "0.1.4",
+  "version": "0.1.5",
   "type": "module",
   "bin": {
     "pullfrog": "dist/cli.mjs",

test/list-aliases.ts

@@ -50,8 +50,9 @@ const FLAGSHIPS = [
 function isPrunablePassthrough(alias: (typeof modelAliases)[number]): boolean {
   if (ROUTING_CANARIES.has(alias.slug)) return false;
   if (alias.provider === "openrouter") return true;
-  // opencode FREE models (big-pickle, mimo, minimax, gpt-5-nano) are unique
-  // to opencode and used in prod — keep them. only prune the keyed mirrors.
+  // opencode FREE models (big-pickle, mimo-v2-pro-free, minimax-m2.5-free)
+  // are unique to opencode and used in prod — keep them. only prune the keyed
+  // mirrors.
   return alias.provider === "opencode" && !alias.isFree;
 }
 

test/models-catalog.main.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { modelAliases } from "../models.ts";
+import { modelAliases, resolveDisplayAlias } from "../models.ts";
 
 // ── catalog drift tests — main-only ─────────────────────────────────────────────
 //
@@ -21,6 +21,7 @@ type ModelsDevModel = {
   name: string;
   status?: string;
   release_date?: string;
+  cost?: { input?: number; output?: number };
 };
 
 type ModelsDevProvider = {
@@ -112,3 +113,70 @@ describe("openRouterResolve OpenRouter API validity", async () => {
     });
   }
 });
+
+// ── OpenCode Zen served-list + free-cost checks ────────────────────────────────
+//
+// these enforce the two dynamic conditions for "this opencode alias works for a
+// user without OPENCODE_API_KEY" — the gap that let issue #691 ship:
+//   1. the alias's terminal-fallback resolve appears in Zen's /v1/models (Zen
+//      actually serves it). caught nothing in #691 because mimo had a fallback
+//      to big-pickle which IS served, but would catch any future alias that
+//      points at a Zen-removed model without a fallback.
+//   2. for isFree aliases, the terminal-fallback's models.dev `cost.input` is
+//      zero. caught the gpt-5-nano regression: $0.05/M input on models.dev,
+//      marked isFree in our catalog.
+//
+// we check the terminal-fallback (via resolveDisplayAlias) because deprecated
+// aliases legitimately point at dead resolve targets — the terminal is what
+// actually runs at the agent CLI.
+
+type ZenModel = { id: string };
+type ZenModelsResponse = { data: ZenModel[] };
+
+const zenApi = fetch("https://opencode.ai/zen/v1/models").then(
+  (r) => r.json() as Promise<ZenModelsResponse>
+);
+
+describe("opencode Zen served list", async () => {
+  const zenData = await zenApi;
+  const zenIds = new Set(zenData.data.map((m) => m.id));
+  const seen = new Set<string>();
+
+  for (const alias of modelAliases) {
+    const terminal = resolveDisplayAlias(alias.slug);
+    if (!terminal) continue;
+    const parsed = parseResolve(terminal.resolve);
+    if (parsed.provider !== "opencode") continue;
+    if (seen.has(terminal.resolve)) continue;
+    seen.add(terminal.resolve);
+
+    it(`${alias.slug} terminal resolve ${terminal.resolve} is served by Zen`, () => {
+      expect(
+        zenIds.has(parsed.modelId),
+        `terminal resolve "${terminal.resolve}" for alias "${alias.slug}" is not in https://opencode.ai/zen/v1/models — Zen no longer serves it. either point a fallback at a Zen-served alias or remove the entry.`
+      ).toBe(true);
+    });
+  }
+});
+
+describe("isFree models.dev cost", async () => {
+  const data = await api;
+  const seen = new Set<string>();
+
+  for (const alias of modelAliases.filter((a) => a.isFree)) {
+    const terminal = resolveDisplayAlias(alias.slug);
+    if (!terminal) continue;
+    const parsed = parseResolve(terminal.resolve);
+    if (seen.has(terminal.resolve)) continue;
+    seen.add(terminal.resolve);
+
+    it(`${alias.slug} terminal resolve ${terminal.resolve} has cost.input === 0`, () => {
+      const model = data[parsed.provider]?.models[parsed.modelId];
+      expect(model, `terminal resolve "${terminal.resolve}" missing on models.dev`).toBeDefined();
+      expect(
+        model?.cost?.input,
+        `isFree alias "${alias.slug}" walks to "${terminal.resolve}" which reports cost.input=${model?.cost?.input} on models.dev — either repoint the fallback or drop \`isFree\``
+      ).toBe(0);
+    });
+  }
+});

test/models.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { modelAliases, resolveCliModel } from "../models.ts";
+import { getModelEnvVars, modelAliases, resolveCliModel, resolveDisplayAlias } from "../models.ts";
 
 // ── pure alias-registry invariants ──────────────────────────────────────────────
 //
@@ -42,3 +42,49 @@ describe("fallback chain resolution", () => {
     });
   }
 });
+
+// ── isFree invariants — sanity-check the catalog data shape ─────────────────────
+//
+// these catch the latent regressions that produced issue #691:
+//   - opencode/gpt-5-nano was marked `isFree` despite costing $0.05/M
+//     (no static check existed; demoted to paid in the same PR adding these tests)
+//   - opencode/mimo-v2-pro-free was free + fallback to big-pickle (correct shape),
+//     but nothing enforced that the terminal of an isFree fallback chain is itself
+//     free. if someone repointed big-pickle's fallback at a paid model, all of mimo
+//     and big-pickle's users would silently start hitting a paid endpoint.
+//
+// the cost.input check itself is network-dependent (lives in
+// models-catalog.main.test.ts); these are the static sibling that runs on every PR.
+describe("isFree invariants", () => {
+  for (const alias of modelAliases.filter((a) => a.isFree)) {
+    it(`${alias.slug} lives under the opencode provider`, () => {
+      expect(
+        alias.provider,
+        `isFree alias "${alias.slug}" must be under "opencode" (Zen's keyless gate is opencode-only)`
+      ).toBe("opencode");
+    });
+
+    it(`${alias.slug} has empty envVars`, () => {
+      expect(
+        getModelEnvVars(alias.slug),
+        `isFree alias "${alias.slug}" must declare \`envVars: []\` so validateAgentApiKey doesn't demand OPENCODE_API_KEY`
+      ).toEqual([]);
+    });
+
+    it(`${alias.slug} has no openRouterResolve`, () => {
+      expect(
+        alias.openRouterResolve,
+        `isFree alias "${alias.slug}" must omit \`openRouterResolve\` — free Zen models don't exist on OpenRouter`
+      ).toBeUndefined();
+    });
+
+    it(`${alias.slug} fallback chain terminates at an isFree alias`, () => {
+      const terminal = resolveDisplayAlias(alias.slug);
+      expect(terminal, `fallback chain for "${alias.slug}" is broken`).toBeDefined();
+      expect(
+        terminal?.isFree,
+        `isFree alias "${alias.slug}" walks to "${terminal?.slug}" which is NOT isFree — users would silently start paying`
+      ).toBe(true);
+    });
+  }
+});

utils/apiFetch.ts

@@ -37,6 +37,18 @@ export async function apiFetch(options: ApiFetchOptions): Promise<Response> {
     headers["x-vercel-protection-bypass"] = bypassSecret;
   }
 
+  // never send Content-Type on body-less requests. empirically, Vercel's
+  // Next.js lambda adapter (Next 16.1.x) throws `SyntaxError: Unexpected
+  // end of data` before delegating to the route handler — returning a 500 —
+  // when Content-Type is set but no body is present. exact mechanism is
+  // unverified (minified runtime frame), but Content-Type on a body-less
+  // request has no defined semantics per RFC 9110 §8.3 anyway. see #692.
+  if (!options.body) {
+    for (const key of Object.keys(headers)) {
+      if (key.toLowerCase() === "content-type") delete headers[key];
+    }
+  }
+
   log.debug(`api fetch: ${options.method ?? "GET"} ${url.pathname}`);
 
   const init: RequestInit = {

utils/apiKeys.test.ts

@@ -27,11 +27,7 @@ describe("validateAgentApiKey", () => {
     });
 
     it("passes for other free opencode models", () => {
-      for (const slug of [
-        "opencode/gpt-5-nano",
-        "opencode/mimo-v2-pro-free",
-        "opencode/minimax-m2.5-free",
-      ]) {
+      for (const slug of ["opencode/mimo-v2-pro-free", "opencode/minimax-m2.5-free"]) {
         expect(() => validateAgentApiKey({ ...base, model: slug })).not.toThrow();
       }
     });
@@ -59,6 +55,12 @@ describe("validateAgentApiKey", () => {
         "no API key found"
       );
     });
+
+    it("throws for opencode/gpt-5-nano without OPENCODE_API_KEY (paid Zen alias)", () => {
+      expect(() => validateAgentApiKey({ ...base, model: "opencode/gpt-5-nano" })).toThrow(
+        "no API key found"
+      );
+    });
   });
 
   describe("no model (auto-select)", () => {

utils/runContext.ts

@@ -88,7 +88,6 @@ export async function fetchRunContext(params: {
   try {
     const headers: Record<string, string> = {
       Authorization: `Bearer ${params.token}`,
-      "Content-Type": "application/json",
     };
     if (params.oidcToken) {
       headers["X-GitHub-OIDC-Token"] = params.oidcToken;