feat(opencode): route cloudflare ai gateway openai and anthropic models through native passthroughs

Co-authored-by: Keefe Tang <keefe@pentagram.me>

packages/core/src/plugin/provider/cloudflare-ai-gateway.ts

@@ -24,9 +24,15 @@ export const CloudflareAIGatewayPlugin = define({
           apiKey: config.apiKey,
           options: gatewayOptions(evt.options, metadata),
         } as any)
-        const unified = createUnified({ apiKey: config.apiKey })
         evt.sdk = {
           languageModel(modelID: string) {
+            // Workers AI is the only first-party provider whose upstream is Cloudflare itself, so it is
+            // the only one that should receive the Cloudflare token as its upstream Authorization header.
+            // The Unified API addresses Workers AI both with the explicit "workers-ai/" prefix and as
+            // bare "@cf/..." ids. Third-party providers must not receive the token; they rely on the
+            // gateway's stored/BYOK keys instead.
+            const isWorkersAi = modelID.startsWith("workers-ai/") || modelID.startsWith("@cf/")
+            const unified = createUnified(isWorkersAi ? { apiKey: config.apiKey } : {})
             return gateway(unified(modelID))
           },
         }

packages/opencode/src/plugin/cloudflare.ts

@@ -61,16 +61,5 @@ export async function CloudflareAIGatewayAuthPlugin(_input: PluginInput): Promis
         },
       ],
     },
-    "chat.params": async (input, output) => {
-      if (input.model.providerID !== "cloudflare-ai-gateway") return
-      // The unified gateway routes through @ai-sdk/openai-compatible, which
-      // always emits max_tokens. OpenAI reasoning models (gpt-5.x, o-series)
-      // reject that field and require max_completion_tokens instead, and the
-      // compatible SDK has no way to rename it. Drop the cap so OpenAI falls
-      // back to the model's default output budget.
-      if (!input.model.api.id.toLowerCase().startsWith("openai/")) return
-      if (!input.model.capabilities.reasoning) return
-      output.maxOutputTokens = undefined
-    },
   }
 }

packages/opencode/src/provider/provider.ts

@@ -800,9 +800,10 @@ function custom(dep: CustomDep): Record<string, CustomLoader> {
         )
       }
 
-      // Use official ai-gateway-provider package (v2.x for AI SDK v5 compatibility)
       const { createAiGateway } = yield* Effect.promise(() => import("ai-gateway-provider"))
       const { createUnified } = yield* Effect.promise(() => import("ai-gateway-provider/providers/unified"))
+      const { createOpenAI } = yield* Effect.promise(() => import("ai-gateway-provider/providers/openai"))
+      const { createAnthropic } = yield* Effect.promise(() => import("ai-gateway-provider/providers/anthropic"))
 
       const metadata = iife(() => {
         if (input.options?.metadata) return input.options.metadata
@@ -829,12 +830,24 @@ function custom(dep: CustomDep): Record<string, CustomLoader> {
         apiKey: apiToken,
         ...(Object.values(opts).some((v) => v !== undefined) ? { options: opts } : {}),
       })
-      const unified = createUnified({ apiKey: apiToken })
-
       return {
         autoload: true,
         async getModel(_sdk: any, modelID: string, _options?: Record<string, any>) {
-          // Model IDs use Unified API format: provider/model (e.g., "anthropic/claude-sonnet-4-5")
+          // Model IDs use Unified API format: provider/model (e.g., "anthropic/claude-sonnet-4-5").
+          // OpenAI and Anthropic ride their native passthrough routes so agents get the Responses
+          // and Messages APIs; new OpenAI models reject tools+reasoning_effort on chat completions.
+          // The passthrough wrappers inject a CF_TEMP_TOKEN sentinel that the gateway strips before
+          // dispatch, so upstream billing stays on the gateway (Unified Billing / stored BYOK).
+          if (modelID.startsWith("openai/")) return aigateway(createOpenAI()(modelID.slice("openai/".length)))
+          if (modelID.startsWith("anthropic/"))
+            return aigateway(createAnthropic()(modelID.slice("anthropic/".length)))
+          // Workers AI is the only first-party provider whose upstream is Cloudflare itself, so it is
+          // the only one that should receive the Cloudflare token as its upstream Authorization header.
+          // The Unified API addresses Workers AI both with the explicit "workers-ai/" prefix and as
+          // bare "@cf/..." ids. Third-party providers must not receive the token; they rely on the
+          // gateway's stored/BYOK keys instead.
+          const isWorkersAi = modelID.startsWith("workers-ai/") || modelID.startsWith("@cf/")
+          const unified = createUnified(isWorkersAi ? { apiKey: apiToken } : {})
           return aigateway(unified(modelID))
         },
         options: {},
@@ -1209,6 +1222,17 @@ function cost(c: ModelsDev.Model["cost"]): Model["cost"] {
   return result
 }
 
+// Cloudflare AI Gateway routes OpenAI and Anthropic models through their native
+// passthrough SDKs (Responses / Messages APIs). Resolving the native npm before
+// variants are computed makes reasoning variants produce payloads the native
+// SDKs understand (e.g. anthropic `effort` instead of compat `reasoningEffort`).
+function cloudflareGatewayNpm(providerID: string, modelID: string) {
+  if (providerID !== "cloudflare-ai-gateway") return undefined
+  if (modelID.startsWith("openai/")) return "@ai-sdk/openai"
+  if (modelID.startsWith("anthropic/")) return "@ai-sdk/anthropic"
+  return undefined
+}
+
 function fromModelsDevModel(provider: ModelsDev.Provider, model: ModelsDev.Model): Model {
   const base: Model = {
     id: ModelV2.ID.make(model.id),
@@ -1218,7 +1242,11 @@ function fromModelsDevModel(provider: ModelsDev.Provider, model: ModelsDev.Model
     api: {
       id: model.id,
       url: model.provider?.api ?? provider.api ?? "",
-      npm: model.provider?.npm ?? provider.npm ?? "@ai-sdk/openai-compatible",
+      npm:
+        cloudflareGatewayNpm(provider.id, model.id) ??
+        model.provider?.npm ??
+        provider.npm ??
+        "@ai-sdk/openai-compatible",
     },
     status: model.status ?? "active",
     headers: {},
@@ -1440,6 +1468,9 @@ const layer = Layer.effect(
               model.provider?.npm ??
               provider.npm ??
               existingModel?.api.npm ??
+              // Config-defined gateway models bypass fromModelsDevModel, so resolve the
+              // native passthrough npm here before falling back to the catalog default.
+              cloudflareGatewayNpm(providerID, apiID) ??
               modelsDev[providerID]?.npm ??
               "@ai-sdk/openai-compatible"
             const name = iife(() => {
@@ -1619,6 +1650,7 @@ const layer = Layer.effect(
 
           for (const [modelID, model] of Object.entries(provider.models)) {
             model.api.id = model.api.id ?? model.id ?? modelID
+
             if (
               // These chat aliases are invalid for the special handling in the
               // built-in providers below, but custom providers may support them.

packages/opencode/test/plugin/cloudflare.test.ts

@@ -13,56 +13,13 @@ const pluginInput = {
   $: {} as never,
 }
 
-function makeHookInput(overrides: { providerID?: string; apiId?: string; reasoning?: boolean }) {
-  return {
-    sessionID: "s",
-    agent: "a",
-    provider: {} as never,
-    message: {} as never,
-    model: {
-      providerID: overrides.providerID ?? "cloudflare-ai-gateway",
-      api: { id: overrides.apiId ?? "openai/gpt-5.2-codex", url: "", npm: "ai-gateway-provider" },
-      capabilities: {
-        reasoning: overrides.reasoning ?? true,
-        temperature: false,
-        attachment: true,
-        toolcall: true,
-        input: { text: true, audio: false, image: false, video: false, pdf: false },
-        output: { text: true, audio: false, image: false, video: false, pdf: false },
-        interleaved: false,
-      },
-    } as never,
-  }
-}
-
-function makeHookOutput() {
-  return { temperature: 0, topP: 1, topK: 0, maxOutputTokens: 32_000 as number | undefined, options: {} }
-}
-
-test("omits maxOutputTokens for openai reasoning models on cloudflare-ai-gateway", async () => {
+test("registers the cloudflare-ai-gateway auth method", async () => {
   const hooks = await CloudflareAIGatewayAuthPlugin(pluginInput)
-  const out = makeHookOutput()
-  await hooks["chat.params"]!(makeHookInput({ apiId: "openai/gpt-5.2-codex", reasoning: true }), out)
-  expect(out.maxOutputTokens).toBeUndefined()
+  expect(hooks.auth?.provider).toBe("cloudflare-ai-gateway")
+  expect(hooks.auth?.methods).toHaveLength(1)
 })
 
-test("keeps maxOutputTokens for openai non-reasoning models", async () => {
+test("no longer drops maxOutputTokens; OpenAI models ride the Responses API passthrough", async () => {
   const hooks = await CloudflareAIGatewayAuthPlugin(pluginInput)
-  const out = makeHookOutput()
-  await hooks["chat.params"]!(makeHookInput({ apiId: "openai/gpt-4-turbo", reasoning: false }), out)
-  expect(out.maxOutputTokens).toBe(32_000)
-})
-
-test("keeps maxOutputTokens for non-openai reasoning models on cloudflare-ai-gateway", async () => {
-  const hooks = await CloudflareAIGatewayAuthPlugin(pluginInput)
-  const out = makeHookOutput()
-  await hooks["chat.params"]!(makeHookInput({ apiId: "anthropic/claude-sonnet-4-5", reasoning: true }), out)
-  expect(out.maxOutputTokens).toBe(32_000)
-})
-
-test("ignores non-cloudflare-ai-gateway providers", async () => {
-  const hooks = await CloudflareAIGatewayAuthPlugin(pluginInput)
-  const out = makeHookOutput()
-  await hooks["chat.params"]!(makeHookInput({ providerID: "openai", apiId: "gpt-5.2-codex", reasoning: true }), out)
-  expect(out.maxOutputTokens).toBe(32_000)
+  expect(hooks["chat.params"]).toBeUndefined()
 })

packages/opencode/test/provider/cf-ai-gateway-e2e.test.ts

@@ -1,22 +1,26 @@
-// End-to-end regression test for opencode#24432.
+// End-to-end regression tests for opencode#24432 and opencode#32051/#32052.
 //
-// Routes through the actual ai-gateway-provider + @ai-sdk/openai-compatible
-// chain that provider.ts:811 builds at runtime, with only the network boundary
-// stubbed. Asserts that `reasoning_effort` (and other provider options the
-// transform emits) actually land in the body Cloudflare AI Gateway forwards
-// upstream, which is the only place the bug was observable.
+// Routes through the actual ai-gateway-provider chain that provider.ts builds at
+// runtime, with only the network boundary stubbed:
+//   - openai/*    -> native OpenAI passthrough (Responses API)
+//   - anthropic/* -> native Anthropic passthrough (Messages API)
+//   - everything else -> unified /compat (openai-compatible chat completions)
+// Asserts what actually lands in the envelope body Cloudflare AI Gateway
+// forwards upstream, which is the only place these bugs were observable.
 
 import { afterEach, beforeEach, describe, expect, test } from "bun:test"
 import type { JSONValue } from "ai"
 import { generateText } from "ai"
 import { createAiGateway } from "ai-gateway-provider"
 import { createUnified } from "ai-gateway-provider/providers/unified"
+import { createOpenAI } from "ai-gateway-provider/providers/openai"
+import { createAnthropic } from "ai-gateway-provider/providers/anthropic"
 import { ProviderTransform } from "@/provider/transform"
 import type * as Provider from "@/provider/provider"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { ModelV2 } from "@opencode-ai/core/model"
 
-type Captured = { url: string; outerBody: unknown }
+type Captured = { url: string; outerBody: unknown; headers: Record<string, string> }
 type ProviderOptions = Record<string, Record<string, JSONValue>>
 
 const realFetch = globalThis.fetch
@@ -26,24 +30,76 @@ function isRecord(value: unknown): value is Record<string, unknown> {
   return typeof value === "object" && value !== null && !Array.isArray(value)
 }
 
+// The gateway returns the upstream provider's response body verbatim, so the
+// mock must answer in the wire format of the step's target provider.
+function upstreamResponseBody(provider: string | undefined) {
+  if (provider === "openai")
+    return {
+      id: "resp_test",
+      object: "response",
+      created_at: 0,
+      model: "gpt-5.4",
+      status: "completed",
+      error: null,
+      incomplete_details: null,
+      output: [
+        {
+          type: "message",
+          role: "assistant",
+          id: "msg_1",
+          status: "completed",
+          content: [{ type: "output_text", text: "ok", annotations: [] }],
+        },
+      ],
+      usage: {
+        input_tokens: 1,
+        input_tokens_details: { cached_tokens: 0 },
+        output_tokens: 1,
+        output_tokens_details: { reasoning_tokens: 0 },
+        total_tokens: 2,
+      },
+    }
+  if (provider === "anthropic")
+    return {
+      id: "msg_test",
+      type: "message",
+      role: "assistant",
+      model: "claude-sonnet-4-6",
+      content: [{ type: "text", text: "ok" }],
+      stop_reason: "end_turn",
+      stop_sequence: null,
+      usage: { input_tokens: 1, output_tokens: 1 },
+    }
+  return {
+    id: "chatcmpl-test",
+    object: "chat.completion",
+    created: 0,
+    model: "test",
+    choices: [{ index: 0, message: { role: "assistant", content: "ok" }, finish_reason: "stop" }],
+    usage: { prompt_tokens: 1, completion_tokens: 1, total_tokens: 2 },
+  }
+}
+
 beforeEach(() => {
   captured = null
   const handle = async (input: Parameters<typeof fetch>[0], init?: Parameters<typeof fetch>[1]): Promise<Response> => {
     const url = typeof input === "string" ? input : input instanceof URL ? input.toString() : input.url
     if (url.startsWith("https://gateway.ai.cloudflare.com/")) {
       const bodyText = typeof init?.body === "string" ? init.body : ""
-      captured = { url, outerBody: bodyText ? JSON.parse(bodyText) : null }
-      return new Response(
-        JSON.stringify({
-          id: "chatcmpl-test",
-          object: "chat.completion",
-          created: 0,
-          model: "openai/gpt-5.4",
-          choices: [{ index: 0, message: { role: "assistant", content: "ok" }, finish_reason: "stop" }],
-          usage: { prompt_tokens: 1, completion_tokens: 1, total_tokens: 2 },
-        }),
-        { status: 200, headers: { "Content-Type": "application/json" } },
-      )
+      const outerBody = bodyText ? JSON.parse(bodyText) : null
+      captured = {
+        url,
+        outerBody,
+        headers: Object.fromEntries(new Headers(init?.headers).entries()),
+      }
+      const provider =
+        Array.isArray(outerBody) && isRecord(outerBody[0]) && typeof outerBody[0].provider === "string"
+          ? outerBody[0].provider
+          : undefined
+      return new Response(JSON.stringify(upstreamResponseBody(provider)), {
+        status: 200,
+        headers: { "Content-Type": "application/json" },
+      })
     }
     return realFetch(input, init)
   }
@@ -56,11 +112,19 @@ afterEach(() => {
   globalThis.fetch = realFetch
 })
 
+// Mirrors the runtime npm rewrite in provider.ts: openai/anthropic models carry
+// their native SDK package so transforms key provider options correctly.
+const cfNpm = (apiId: string) => {
+  if (apiId.startsWith("openai/")) return "@ai-sdk/openai"
+  if (apiId.startsWith("anthropic/")) return "@ai-sdk/anthropic"
+  return "ai-gateway-provider"
+}
+
 const cfModel = (apiId: string, releaseDate = "2026-03-05"): Provider.Model => ({
   id: ModelV2.ID.make(`cloudflare-ai-gateway/${apiId}`),
   providerID: ProviderV2.ID.make("cloudflare-ai-gateway"),
   name: apiId,
-  api: { id: apiId, url: "https://gateway.ai.cloudflare.com/v1/compat", npm: "ai-gateway-provider" },
+  api: { id: apiId, url: "https://gateway.ai.cloudflare.com/v1/compat", npm: cfNpm(apiId) },
   capabilities: {
     reasoning: true,
     temperature: false,
@@ -80,53 +144,165 @@ const cfModel = (apiId: string, releaseDate = "2026-03-05"): Provider.Model => (
 
 // ai-gateway-provider sends an array of step descriptors; each entry's `query`
 // is the body forwarded to the upstream provider.
-function extractUpstreamQuery(body: unknown): Record<string, unknown> | undefined {
+function firstStep(body: unknown): Record<string, unknown> | undefined {
   if (!Array.isArray(body) || body.length === 0) return undefined
   const first = body[0]
-  if (!isRecord(first)) return undefined
-  const query = first.query
+  return isRecord(first) ? first : undefined
+}
+
+function extractUpstreamQuery(body: unknown): Record<string, unknown> | undefined {
+  const query = firstStep(body)?.query
   return isRecord(query) ? query : undefined
 }
 
-async function callThroughGateway(apiId: string, providerOptions: ProviderOptions) {
-  const aigateway = createAiGateway({ accountId: "test", gateway: "test", apiKey: "test" })
-  const unified = createUnified()
-  await generateText({ model: aigateway(unified(apiId)), prompt: "hi", providerOptions })
+// Each step descriptor also carries the `headers` forwarded to the upstream provider.
+function extractUpstreamHeaders(body: unknown): Record<string, unknown> | undefined {
+  const headers = firstStep(body)?.headers
+  return isRecord(headers) ? headers : undefined
+}
+
+// Mirrors the runtime routing in provider.ts getModel.
+function gatewayModel(apiId: string, gatewayToken = "test") {
+  const aigateway = createAiGateway({ accountId: "test", gateway: "test", apiKey: gatewayToken })
+  if (apiId.startsWith("openai/")) return aigateway(createOpenAI()(apiId.slice("openai/".length)))
+  if (apiId.startsWith("anthropic/")) return aigateway(createAnthropic()(apiId.slice("anthropic/".length)))
+  const isWorkersAi = apiId.startsWith("workers-ai/") || apiId.startsWith("@cf/")
+  const unified = createUnified(isWorkersAi ? { apiKey: gatewayToken } : {})
+  return aigateway(unified(apiId))
+}
+
+async function callThroughGateway(apiId: string, providerOptions: ProviderOptions, gatewayToken = "test") {
+  await generateText({ model: gatewayModel(apiId, gatewayToken), prompt: "hi", providerOptions })
   return extractUpstreamQuery(captured?.outerBody)
 }
 
+describe("cf-ai-gateway routing", () => {
+  test("openai/* rides the native OpenAI passthrough on the Responses API", async () => {
+    await callThroughGateway("openai/gpt-5.4", {})
+    const step = firstStep(captured?.outerBody)
+    expect(step?.provider).toBe("openai")
+    expect(step?.endpoint).toBe("v1/responses")
+    const upstream = extractUpstreamQuery(captured?.outerBody)
+    expect(upstream?.model).toBe("gpt-5.4")
+  })
+
+  test("anthropic/* rides the native Anthropic passthrough on the Messages API", async () => {
+    await callThroughGateway("anthropic/claude-sonnet-4-6", {})
+    const step = firstStep(captured?.outerBody)
+    expect(step?.provider).toBe("anthropic")
+    expect(step?.endpoint).toBe("v1/messages")
+    const upstream = extractUpstreamQuery(captured?.outerBody)
+    expect(upstream?.model).toBe("claude-sonnet-4-6")
+  })
+
+  test("workers-ai models stay on the unified /compat route", async () => {
+    await callThroughGateway("workers-ai/@cf/moonshotai/kimi-k2.6", {})
+    const step = firstStep(captured?.outerBody)
+    expect(step?.provider).toBe("compat")
+    expect(step?.endpoint).toBe("chat/completions")
+    const upstream = extractUpstreamQuery(captured?.outerBody)
+    expect(upstream?.model).toBe("workers-ai/@cf/moonshotai/kimi-k2.6")
+  })
+})
+
 describe("cf-ai-gateway end-to-end (regression: #24432)", () => {
-  test("ProviderTransform.providerOptions output puts reasoning_effort on the wire", async () => {
-    // The full chain the runtime exercises:
-    //   transform.providerOptions() -> openaiCompatible key
-    //   -> @ai-sdk/openai-compatible reads it as compatibleOptions
-    //   -> emits body.reasoning_effort
+  test("ProviderTransform.providerOptions output puts reasoning effort on the Responses wire", async () => {
+    // The full chain the runtime exercises for OpenAI models:
+    //   transform.providerOptions() -> "openai" key (npm rewritten to @ai-sdk/openai)
+    //   -> OpenAIResponsesLanguageModel emits body.reasoning.effort
     //   -> ai-gateway-provider wraps the body and forwards to gateway.ai.cloudflare.com
     const opts = ProviderTransform.providerOptions(cfModel("openai/gpt-5.4"), { reasoningEffort: "xhigh" })
-    expect(opts).toEqual({ openaiCompatible: { reasoningEffort: "xhigh" } })
+    expect(Object.keys(opts)).toEqual(["openai"])
+    expect(opts.openai.reasoningEffort).toBe("xhigh")
 
     const upstream = await callThroughGateway("openai/gpt-5.4", opts)
-    expect(upstream?.reasoning_effort).toBe("xhigh")
+    expect((upstream?.reasoning as Record<string, unknown> | undefined)?.effort).toBe("xhigh")
   })
 
   test("variants() output for openai/gpt-5.4 lands xhigh on the wire", async () => {
-    // The other half of the bug: workflow `variant: xhigh` flows through variants()
-    // and must reach the wire. variants() returns the providerOptions payload
-    // unwrapped; providerOptions() wraps it under the SDK key.
+    // fromModelsDevModel resolves the native npm before computing variants, so
+    // OpenAI models get full Responses-flavored payloads (summary + encrypted
+    // reasoning include for stateless multi-turn reasoning).
     const variants = ProviderTransform.variants(cfModel("openai/gpt-5.4"))
-    expect(variants.xhigh).toEqual({ reasoningEffort: "xhigh" })
+    expect(variants.xhigh).toEqual({
+      reasoningEffort: "xhigh",
+      reasoningSummary: "auto",
+      include: ["reasoning.encrypted_content"],
+    })
 
     const opts = ProviderTransform.providerOptions(cfModel("openai/gpt-5.4"), variants.xhigh)
     const upstream = await callThroughGateway("openai/gpt-5.4", opts)
-    expect(upstream?.reasoning_effort).toBe("xhigh")
+    const reasoning = upstream?.reasoning as Record<string, unknown> | undefined
+    expect(reasoning?.effort).toBe("xhigh")
+    expect(reasoning?.summary).toBe("auto")
+  })
+
+  test("reasoning effort variants for anthropic models land as native adaptive thinking", async () => {
+    // Mirrors the runtime catalog path: models.dev reasoning_options -> reasoningVariants
+    // computed on the native @ai-sdk/anthropic npm -> adaptive thinking + output_config.effort.
+    const model = cfModel("anthropic/claude-sonnet-4-6")
+    const variants = ProviderTransform.reasoningVariants(
+      { reasoning_options: [{ type: "effort", values: ["low", "medium", "high"] }] } as never,
+      model,
+    )
+    expect(variants?.high).toMatchObject({ effort: "high" })
+
+    const opts = ProviderTransform.providerOptions(model, variants!.high)
+    expect(Object.keys(opts)).toEqual(["anthropic"])
+
+    const upstream = await callThroughGateway("anthropic/claude-sonnet-4-6", opts)
+    expect((upstream?.thinking as Record<string, unknown> | undefined)?.type).toBe("adaptive")
+    expect((upstream?.output_config as Record<string, unknown> | undefined)?.effort).toBe("high")
+  })
+
+  test("reasoning_effort still reaches the /compat wire for workers-ai models", async () => {
+    const model = cfModel("workers-ai/@cf/moonshotai/kimi-k2.6")
+    const opts = ProviderTransform.providerOptions(model, { reasoningEffort: "high" })
+    expect(opts).toEqual({ openaiCompatible: { reasoningEffort: "high" } })
+
+    const upstream = await callThroughGateway("workers-ai/@cf/moonshotai/kimi-k2.6", opts)
+    expect(upstream?.reasoning_effort).toBe("high")
   })
 
   test("legacy buggy key 'cloudflare-ai-gateway' does NOT reach the wire (proves the bug)", async () => {
     // Sanity: confirms the bug class. If a future change accidentally restores
     // providerID-keyed providerOptions, this test fails before users notice.
-    const upstream = await callThroughGateway("openai/gpt-5.4", {
+    const upstream = await callThroughGateway("workers-ai/@cf/moonshotai/kimi-k2.6", {
       "cloudflare-ai-gateway": { reasoningEffort: "high" },
     })
     expect(upstream?.reasoning_effort).toBeUndefined()
   })
 })
+
+describe("cf-ai-gateway token scoping (regression: #32051/#32052)", () => {
+  test("openai passthrough does NOT forward the Cloudflare token upstream", async () => {
+    await callThroughGateway("openai/gpt-5.4", {}, "cf-gateway-secret")
+
+    expect(captured?.headers["cf-aig-authorization"]).toBe("Bearer cf-gateway-secret")
+    // Security invariant: the Cloudflare token must never become the upstream provider's Authorization.
+    expect(extractUpstreamHeaders(captured?.outerBody)?.["authorization"]).toBeUndefined()
+    expect(JSON.stringify(captured?.outerBody)).not.toContain("cf-gateway-secret")
+  })
+
+  test("anthropic passthrough does NOT forward the Cloudflare token upstream", async () => {
+    await callThroughGateway("anthropic/claude-sonnet-4-6", {}, "cf-gateway-secret")
+
+    expect(captured?.headers["cf-aig-authorization"]).toBe("Bearer cf-gateway-secret")
+    expect(extractUpstreamHeaders(captured?.outerBody)?.["x-api-key"]).toBeUndefined()
+    expect(JSON.stringify(captured?.outerBody)).not.toContain("cf-gateway-secret")
+  })
+
+  test("workers-ai models DO forward the Cloudflare token upstream", async () => {
+    await callThroughGateway("workers-ai/@cf/google/gemma-4-26b-a4b-it", {}, "cf-gateway-secret")
+
+    expect(captured?.headers["cf-aig-authorization"]).toBe("Bearer cf-gateway-secret")
+    expect(extractUpstreamHeaders(captured?.outerBody)?.["authorization"]).toBe("Bearer cf-gateway-secret")
+  })
+
+  test("bare @cf/ Workers AI models DO forward the Cloudflare token upstream", async () => {
+    await callThroughGateway("@cf/meta/llama-3.1-8b-instruct", {}, "cf-gateway-secret")
+
+    expect(captured?.headers["cf-aig-authorization"]).toBe("Bearer cf-gateway-secret")
+    expect(extractUpstreamHeaders(captured?.outerBody)?.["authorization"]).toBe("Bearer cf-gateway-secret")
+  })
+})