diff --git a/server/src/__tests__/opencode-local-execute.test.ts b/server/src/__tests__/opencode-local-execute.test.ts
new file mode 100644
index 0000000000..0bd5c584f9
--- /dev/null
+++ b/server/src/__tests__/opencode-local-execute.test.ts
@@ -0,0 +1,182 @@
+import { describe, expect, it } from "vitest";
+import fs from "node:fs/promises";
+import os from "node:os";
+import path from "node:path";
+import { execute } from "@paperclipai/adapter-opencode-local/server";
+
+async function writeFakeOpenCodeCommand(commandPath: string): Promise<void> {
+  const script = `#!/usr/bin/env node
+const fs = require("node:fs");
+const path = require("node:path");
+
+const args = process.argv.slice(2);
+const capturePath = process.env.PAPERCLIP_TEST_CAPTURE_PATH;
+
+if (args[0] === "models") {
+  process.stdout.write("anthropic/claude-opus-4-6\\n");
+  process.exit(0);
+}
+
+let runtimeConfig = null;
+const xdgConfigHome = process.env.XDG_CONFIG_HOME || null;
+if (xdgConfigHome) {
+  const runtimeConfigPath = path.join(xdgConfigHome, "opencode", "opencode.json");
+  if (fs.existsSync(runtimeConfigPath)) {
+    runtimeConfig = JSON.parse(fs.readFileSync(runtimeConfigPath, "utf8"));
+  }
+}
+
+if (capturePath) {
+  fs.writeFileSync(capturePath, JSON.stringify({
+    argv: args,
+    prompt: fs.readFileSync(0, "utf8"),
+    xdgConfigHome,
+    runtimeConfig,
+    paperclipEnvKeys: Object.keys(process.env)
+      .filter((key) => key.startsWith("PAPERCLIP_"))
+      .sort(),
+  }), "utf8");
+}
+
+process.stdout.write(JSON.stringify({ type: "step_start", sessionID: "ses_opencode_1" }) + "\\n");
+process.stdout.write(JSON.stringify({ type: "text", part: { type: "text", text: "hello" } }) + "\\n");
+process.stdout.write(JSON.stringify({
+  type: "step_finish",
+  part: {
+    reason: "stop",
+    cost: 0,
+    tokens: {
+      input: 10,
+      output: 5,
+      cache: { read: 0, write: 0 },
+    },
+  },
+}) + "\\n");
+`;
+  await fs.writeFile(commandPath, script, "utf8");
+  await fs.chmod(commandPath, 0o755);
+}
+
+type CapturePayload = {
+  argv: string[];
+  prompt: string;
+  xdgConfigHome: string | null;
+  runtimeConfig: {
+    permission?: {
+      external_directory?: string;
+      read?: string;
+    };
+    theme?: string;
+  } | null;
+  paperclipEnvKeys: string[];
+};
+
+describe("opencode execute", () => {
+  it("injects external_directory allow config for headless runs", async () => {
+    const root = await fs.mkdtemp(path.join(os.tmpdir(), "paperclip-opencode-execute-"));
+    const workspace = path.join(root, "workspace");
+    const agentHome = path.join(root, "agent-home");
+    const commandPath = path.join(root, "opencode");
+    const capturePath = path.join(root, "capture.json");
+    const sourceConfigHome = path.join(root, "source-config");
+    await fs.mkdir(workspace, { recursive: true });
+    await fs.mkdir(agentHome, { recursive: true });
+    await fs.mkdir(path.join(sourceConfigHome, "opencode"), { recursive: true });
+    await fs.writeFile(
+      path.join(sourceConfigHome, "opencode", "opencode.json"),
+      `${JSON.stringify({ theme: "system", permission: { read: "allow" } }, null, 2)}\n`,
+      "utf8",
+    );
+    await writeFakeOpenCodeCommand(commandPath);
+
+    const previousHome = process.env.HOME;
+    process.env.HOME = root;
+
+    let commandNotes: string[] = [];
+    try {
+      const result = await execute({
+        runId: "run-1",
+        agent: {
+          id: "agent-1",
+          companyId: "company-1",
+          name: "OpenCode Coder",
+          adapterType: "opencode_local",
+          adapterConfig: {},
+        },
+        runtime: {
+          sessionId: null,
+          sessionParams: null,
+          sessionDisplayId: null,
+          taskKey: null,
+        },
+        config: {
+          command: commandPath,
+          cwd: workspace,
+          model: "anthropic/claude-opus-4-6",
+          env: {
+            PAPERCLIP_TEST_CAPTURE_PATH: capturePath,
+            XDG_CONFIG_HOME: sourceConfigHome,
+          },
+          promptTemplate: "Follow the paperclip heartbeat.",
+        },
+        context: {
+          paperclipWorkspace: {
+            cwd: workspace,
+            source: "project_primary",
+            agentHome,
+          },
+        },
+        authToken: "run-jwt-token",
+        onLog: async () => {},
+        onMeta: async (meta) => {
+          commandNotes = meta.commandNotes ?? [];
+        },
+      });
+
+      expect(result.exitCode).toBe(0);
+      expect(result.errorMessage).toBeNull();
+
+      const capture = JSON.parse(await fs.readFile(capturePath, "utf8")) as CapturePayload;
+      expect(capture.argv).toEqual([
+        "run",
+        "--format",
+        "json",
+        "--model",
+        "anthropic/claude-opus-4-6",
+      ]);
+      expect(capture.prompt).toContain("Follow the paperclip heartbeat.");
+      expect(capture.paperclipEnvKeys).toEqual(
+        expect.arrayContaining([
+          "PAPERCLIP_AGENT_ID",
+          "PAPERCLIP_API_KEY",
+          "PAPERCLIP_API_URL",
+          "PAPERCLIP_COMPANY_ID",
+          "PAPERCLIP_RUN_ID",
+          "PAPERCLIP_WORKSPACE_CWD",
+        ]),
+      );
+      expect(capture.runtimeConfig).toMatchObject({
+        theme: "system",
+        permission: {
+          read: "allow",
+          external_directory: "allow",
+        },
+      });
+      expect(commandNotes).toEqual(
+        expect.arrayContaining([
+          "Injected runtime OpenCode config with permission.external_directory=allow to avoid headless approval prompts.",
+        ]),
+      );
+      expect(capture.xdgConfigHome).not.toBe(sourceConfigHome);
+      expect(capture.xdgConfigHome).not.toBeNull();
+      await expect(fs.access(capture.xdgConfigHome!)).rejects.toThrow();
+    } finally {
+      if (previousHome === undefined) {
+        delete process.env.HOME;
+      } else {
+        process.env.HOME = previousHome;
+      }
+      await fs.rm(root, { recursive: true, force: true });
+    }
+  });
+});