fix: carry provider capability in dedicated header

hub/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@paradigm/hub",
-  "version": "0.0.15",
+  "version": "0.0.19",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@paradigm/hub",
-      "version": "0.0.15",
+      "version": "0.0.19",
       "dependencies": {
         "@anthropic-ai/claude-agent-sdk": "^0.3.202",
         "@fastify/cookie": "^11.0.2",

hub/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@paradigm/hub",
-  "version": "0.0.15",
+  "version": "0.0.19",
   "private": true,
   "type": "module",
   "engines": {

hub/src/agent/security.ts

@@ -8,6 +8,7 @@ const PROVIDER_ENV_KEYS = new Set([
   "ANTHROPIC_BASE_URL",
   "ANTHROPIC_AUTH_TOKEN",
   "ANTHROPIC_API_KEY",
+  "ANTHROPIC_CUSTOM_HEADERS",
 ]);
 
 const SAFE_HOST_ENV_KEYS = [
@@ -23,11 +24,6 @@ const SAFE_HOST_ENV_KEYS = [
   "CPH_BIN",
 ] as const;
 
-const SANDBOX_HIDDEN_ENV_KEYS = [
-  "ANTHROPIC_AUTH_TOKEN",
-  "ANTHROPIC_API_KEY",
-] as const;
-
 // Linux sockaddr_un.sun_path is 108 bytes including the terminator. Claude's
 // sandbox appends its own user directory and randomized bridge socket names,
 // so keep our prefix well below that hard limit.
@@ -156,7 +152,9 @@ export async function createAgentSecurityPolicy(input: AgentSecurityInput): Prom
       },
       credentials: {
         files: sensitiveReadPaths.map((path) => ({ path, mode: "deny" as const })),
-        envVars: SANDBOX_HIDDEN_ENV_KEYS.map((name) => ({ name, mode: "deny" as const })),
+        // These values are short-lived loopback capabilities, not Organization
+        // provider secrets. Denying them also strips Claude's own request auth.
+        envVars: [],
       },
     },
   };

hub/src/connections/providerProxy.ts

@@ -20,6 +20,7 @@ const REPLACED_REQUEST_HEADERS = new Set([
   "content-length",
   "host",
   "x-api-key",
+  "x-cph-run-capability",
 ]);
 
 export interface ProviderUpstreamCredential {
@@ -41,6 +42,12 @@ export interface ProviderProxyDiagnostic {
     | "provider_proxy_redirect_refused"
     | "provider_proxy_upstream_failed";
   readonly category: NetworkFailureCategory | "authorization" | "request_limit" | "redirect";
+  readonly authShape?: {
+    readonly bearerLength: number;
+    readonly apiKeyLength: number;
+    readonly customCapabilityLength: number;
+    readonly expectedLength: number;
+  };
 }
 
 export interface ProviderProxyOptions {
@@ -81,7 +88,8 @@ export async function openProviderProxyLease(
     sdkEnv: {
       ANTHROPIC_BASE_URL: `http://127.0.0.1:${address.port}`,
       ANTHROPIC_AUTH_TOKEN: capability,
-      ANTHROPIC_API_KEY: "",
+      ANTHROPIC_API_KEY: capability,
+      ANTHROPIC_CUSTOM_HEADERS: `X-CPH-Run-Capability: ${capability}`,
     },
     sensitiveValues: [capability],
     async close(): Promise<void> {
@@ -102,8 +110,24 @@ async function forwardProviderRequest(
   upstream: ProviderUpstreamCredential,
   options: ProviderProxyOptions,
 ): Promise<void> {
-  if (!authorized(request.headers.authorization, header(request.headers["x-api-key"]), capability)) {
+  if (!authorized(
-    options.onDiagnostic?.({ code: "provider_proxy_unauthorized", category: "authorization" });
+    request.headers.authorization,
+    header(request.headers["x-api-key"]),
+    header(request.headers["x-cph-run-capability"]),
+    capability,
+  )) {
+    options.onDiagnostic?.({
+      code: "provider_proxy_unauthorized",
+      category: "authorization",
+      authShape: {
+        bearerLength: request.headers.authorization?.startsWith("Bearer ")
+          ? request.headers.authorization.length - "Bearer ".length
+          : 0,
+        apiKeyLength: header(request.headers["x-api-key"])?.length ?? 0,
+        customCapabilityLength: header(request.headers["x-cph-run-capability"])?.length ?? 0,
+        expectedLength: capability.length,
+      },
+    });
     response.writeHead(401, { "content-type": "text/plain; charset=utf-8" });
     response.end("unauthorized");
     return;
@@ -168,11 +192,16 @@ async function forwardProviderRequest(
 function authorized(
   authorization: string | undefined,
   apiKey: string | undefined,
+  customCapability: string | undefined,
   capability: string,
 ): boolean {
-  const value = authorization?.startsWith("Bearer ")
+  const bearer = authorization?.startsWith("Bearer ")
     ? authorization.slice("Bearer ".length)
-    : apiKey;
+    : undefined;
+  return [bearer, apiKey, customCapability].some((value) => matchesCapability(value, capability));
+}
+
+function matchesCapability(value: string | undefined, capability: string): boolean {
   if (value === undefined) return false;
   const supplied = Buffer.from(value);
   const expected = Buffer.from(capability);

hub/src/hub.ts

@@ -73,6 +73,7 @@ export async function startHub(): Promise<void> {
           providerId: context.providerId,
           errorCode: diagnostic.code,
           failureCategory: diagnostic.category,
+          authShape: diagnostic.authShape,
         }, "provider proxy diagnostic");
       },
     }),

hub/test/unit/agent-security.test.ts

@@ -66,10 +66,7 @@ describe("agent subprocess security policy", () => {
         allowRead: expect.arrayContaining([canonicalWorkspace, "/usr/bin"]),
       },
       credentials: {
-        envVars: expect.arrayContaining([
+        envVars: [],
-          { name: "ANTHROPIC_AUTH_TOKEN", mode: "deny" },
-          { name: "ANTHROPIC_API_KEY", mode: "deny" },
-        ]),
       },
     });
   });

hub/test/unit/provider-proxy.test.ts

@@ -53,13 +53,15 @@ describe("run-scoped provider proxy", () => {
     expect(lease.sdkEnv).toMatchObject({
       ANTHROPIC_BASE_URL: expect.stringMatching(/^http:\/\/127\.0\.0\.1:\d+$/),
       ANTHROPIC_AUTH_TOKEN: expect.any(String),
-      ANTHROPIC_API_KEY: "",
+      ANTHROPIC_API_KEY: expect.any(String),
+      ANTHROPIC_CUSTOM_HEADERS: expect.stringMatching(/^X-CPH-Run-Capability: /),
     });
+    expect(lease.sdkEnv.ANTHROPIC_AUTH_TOKEN).toBe(lease.sdkEnv.ANTHROPIC_API_KEY);
 
     const response = await fetch(`${lease.sdkEnv.ANTHROPIC_BASE_URL}/v1/messages`, {
       method: "POST",
       headers: {
-        authorization: `Bearer ${lease.sdkEnv.ANTHROPIC_AUTH_TOKEN}`,
+        "x-api-key": lease.sdkEnv.ANTHROPIC_API_KEY ?? "",
         "content-type": "application/json",
         "anthropic-version": "2023-06-01",
       },
@@ -104,7 +106,11 @@ describe("run-scoped provider proxy", () => {
 
     expect(response.status).toBe(401);
     expect(upstreamRequests).toBe(0);
-    expect(diagnostics).toEqual([{ code: "provider_proxy_unauthorized", category: "authorization" }]);
+    expect(diagnostics).toEqual([{
+      code: "provider_proxy_unauthorized",
+      category: "authorization",
+      authShape: { bearerLength: 0, apiKeyLength: 0, customCapabilityLength: 0, expectedLength: 43 },
+    }]);
   });
 
   it("accepts the run capability in the Anthropic x-api-key header", async () => {
@@ -127,7 +133,7 @@ describe("run-scoped provider proxy", () => {
     leases.push(lease);
 
     const response = await fetch(`${lease.sdkEnv.ANTHROPIC_BASE_URL}/v1/messages`, {
-      headers: { "x-api-key": lease.sdkEnv.ANTHROPIC_AUTH_TOKEN ?? "" },
+      headers: { "x-api-key": lease.sdkEnv.ANTHROPIC_API_KEY ?? "" },
     });
 
     expect(response.status).toBe(200);
@@ -167,7 +173,7 @@ describe("run-scoped provider proxy", () => {
     leases.push(lease);
 
     const response = await fetch(`${lease.sdkEnv.ANTHROPIC_BASE_URL}/v1/messages`, {
-      headers: { authorization: `Bearer ${lease.sdkEnv.ANTHROPIC_AUTH_TOKEN}` },
+      headers: { "x-api-key": lease.sdkEnv.ANTHROPIC_API_KEY ?? "" },
       redirect: "manual",
     });
 

hub/test/unit/runner.test.ts

@@ -288,10 +288,7 @@ describe("runAgent", () => {
         },
         sandbox: {
           credentials: {
-            envVars: expect.arrayContaining([
+            envVars: [],
-              { name: "ANTHROPIC_AUTH_TOKEN", mode: "deny" },
-              { name: "ANTHROPIC_API_KEY", mode: "deny" },
-            ]),
           },
         },
       },