diff --git a/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.test.ts b/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.test.ts
index 89bb57f7aec..ddd01a4982e 100644
--- a/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.test.ts
+++ b/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.test.ts
@@ -2262,16 +2262,20 @@ describe("OpenCodeServerDriver", () => {
     const exitingFixture = join(root, "exit-before-health.mjs");
     await writeFile(
       exitingFixture,
-      "#!/usr/bin/env node\nprocess.stderr.write(`credential=${process.env.OPENROUTER_API_KEY}\\nauthorization=super-secret-opencode-token\\n`);\nprocess.exit(17);\n",
+      "#!/usr/bin/env node\nimport { readFileSync } from 'node:fs';\nconst config = JSON.parse(readFileSync(`${process.env.XDG_CONFIG_HOME}/opencode/opencode.json`, 'utf8'));\nprocess.stderr.write(`credential=${process.env.OPENROUTER_API_KEY}\\ngateway=${config.provider.paperclip.options.apiKey}\\nauthorization=super-secret-opencode-token\\n`);\nprocess.exit(17);\n",
       { mode: 0o755 },
     );
+    const diagnostics: string[] = [];
     const driver = new OpenCodeServerDriver({
-      model: "openrouter/deepseek/deepseek-v4-flash-0731",
+      model: "paperclip/team/model-alias",
       runtimeDirectory: root,
       command: exitingFixture,
+      onDiagnostic: (message) => { diagnostics.push(message); },
       environment: {
         PATH: process.env.PATH,
         OPENROUTER_API_KEY: "fixture-key",
+        PAPERCLIP_AI_PROVIDER_KEY: "fixture-custom-gateway-key",
+        PAPERCLIP_AI_PROVIDER_URL: "https://gateway.example/v1",
       },
     });
     const error = await driver
@@ -2289,6 +2293,41 @@ describe("OpenCodeServerDriver", () => {
     expect(error).toContain("stage=health");
     expect(error).toContain("[REDACTED]");
     expect(error).not.toContain("fixture-key");
+    expect(error).not.toContain("fixture-custom-gateway-key");
     expect(error).not.toContain("super-secret-opencode-token");
+    expect(diagnostics.join("")).toContain("gateway=[REDACTED]");
+    expect(diagnostics.join("")).not.toContain("fixture-custom-gateway-key");
+  });
+
+  it.each(["network", "response"])("redacts custom gateway keys in %s errors", async (failure) => {
+    await chmod(fixture, 0o755);
+    const root = await mkdtemp(join(tmpdir(), "paperclip-opencode-driver-"));
+    const workspace = await mkdtemp(join(tmpdir(), "paperclip-opencode-workspace-"));
+    roots.push(root, workspace);
+    const key = "fixture-custom-gateway-key";
+    const driver = new OpenCodeServerDriver({
+      model: "paperclip/team/model-alias",
+      runtimeDirectory: root,
+      command: fixture,
+      environment: {
+        PATH: process.env.PATH,
+        PAPERCLIP_AI_PROVIDER_KEY: key,
+        PAPERCLIP_AI_PROVIDER_URL: "https://gateway.example/v1",
+      },
+      fetch: async (input, init) => {
+        if (String(input).endsWith("/session") && init?.method === "POST") {
+          if (failure === "network") throw new Error(`Gateway rejected ${key}`);
+          return new Response(`Gateway rejected ${key}`, { status: 400 });
+        }
+        return fetch(input, init);
+      },
+    });
+    const error = await driver.openSession({
+      runId: "run-gateway-error",
+      normalizedSessionId: "gateway-error",
+      workingDirectory: workspace,
+    }).then(() => "provider unexpectedly started", (cause: unknown) => String(cause));
+    expect(error).toContain("Gateway rejected [REDACTED]");
+    expect(error).not.toContain(key);
   });
 });
diff --git a/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.ts b/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.ts
index 4a68460e053..ed4fc96b5a3 100644
--- a/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.ts
+++ b/packages/paperclip-runner/src/drivers/opencode/opencode-server-driver.ts
@@ -254,6 +254,7 @@ export class OpenCodeServerDriver implements HarnessDriver {
         recovered: false,
         reason: redact(String(error), [
           this.#options.environment?.OPENROUTER_API_KEY,
+          this.#options.environment?.PAPERCLIP_AI_PROVIDER_KEY,
         ]),
       };
     }
@@ -1970,14 +1971,15 @@ async function startRuntime(input: {
   const assignedMcp = nativeMcpLaunchBinding(
     input.options.environment ?? process.env,
   );
-  input.trace?.addSensitiveValues([
+  const sensitiveValues = [
     password,
     authHeader,
     bridge.secret,
     assignedMcp?.token,
     input.options.environment?.OPENROUTER_API_KEY,
     input.options.environment?.PAPERCLIP_AI_PROVIDER_KEY,
-  ]);
+  ].filter((value): value is string => Boolean(value));
+  input.trace?.addSensitiveValues(sensitiveValues);
   const instructionRoot =
     input.options.runtimeContext?.instructions.bundle.rootPath;
   const [modelProvider, ...modelIdParts] = input.options.model.split("/");
@@ -2089,10 +2091,7 @@ async function startRuntime(input: {
   let diagnostics = "";
   child.stderr?.on("data", (chunk) => {
     const raw = Buffer.isBuffer(chunk) ? chunk : Buffer.from(String(chunk));
-    const redactedDiagnostic = redact(raw.toString("utf8"), [
-      password,
-      input.options.environment?.OPENROUTER_API_KEY,
-    ]);
+    const redactedDiagnostic = redact(raw.toString("utf8"), sensitiveValues);
     diagnostics = `${diagnostics}${redactedDiagnostic}`.slice(-8_192);
     const frameId = input.trace?.frame({
       direction: "provider_stderr",
@@ -2155,10 +2154,7 @@ async function startRuntime(input: {
       process: child,
       bridge,
       trace: input.trace,
-      sensitiveValues: [
-        password,
-        input.options.environment?.OPENROUTER_API_KEY,
-      ].filter((value): value is string => Boolean(value)),
+      sensitiveValues,
       close: async (closeInput = {}) => {
         await bridge.close().catch(() => {});
         if (child.exitCode === null && child.signalCode === null && child.pid) {