diff --git a/packages/adapters/claude-local/src/server/test.ts b/packages/adapters/claude-local/src/server/test.ts
index 2aefa947fc..a6abb2605e 100644
--- a/packages/adapters/claude-local/src/server/test.ts
+++ b/packages/adapters/claude-local/src/server/test.ts
@@ -12,6 +12,7 @@ import {
   ensurePathInEnv,
 } from "@paperclipai/adapter-utils/server-utils";
 import {
+  adapterExecutionTargetIsCommandBacked,
   ensureAdapterExecutionTargetCommandResolvable,
   ensureAdapterExecutionTargetDirectory,
   runAdapterExecutionTargetProcess,
@@ -90,7 +91,7 @@ export async function testEnvironment(
   const command = asString(config.command, "claude");
   const target = ctx.executionTarget ?? null;
   const targetIsRemote = target?.kind === "remote";
-  const targetIsSandbox = target?.kind === "remote" && target.transport === "sandbox";
+  const targetIsSandbox = adapterExecutionTargetIsCommandBacked(target);
   const cwd = resolveAdapterExecutionTargetCwd(target, asString(config.cwd, ""), process.cwd());
   const runId = `claude-envtest-${Date.now()}-${Math.random().toString(16).slice(2)}`;
 
diff --git a/packages/adapters/codex-local/src/server/test.ts b/packages/adapters/codex-local/src/server/test.ts
index 10cbcb8d39..d5b5a1076d 100644
--- a/packages/adapters/codex-local/src/server/test.ts
+++ b/packages/adapters/codex-local/src/server/test.ts
@@ -9,6 +9,7 @@ import {
   ensurePathInEnv,
 } from "@paperclipai/adapter-utils/server-utils";
 import {
+  adapterExecutionTargetIsCommandBacked,
   ensureAdapterExecutionTargetCommandResolvable,
   ensureAdapterExecutionTargetDirectory,
   maybeRunSandboxInstallCommand,
@@ -277,7 +278,7 @@ export async function testEnvironment(
   const command = asString(config.command, "codex");
   const target = ctx.executionTarget ?? null;
   const targetIsRemote = target?.kind === "remote";
-  const targetIsSandbox = target?.kind === "remote" && target.transport === "sandbox";
+  const targetIsSandbox = adapterExecutionTargetIsCommandBacked(target);
   const cwd = resolveAdapterExecutionTargetCwd(target, asString(config.cwd, ""), process.cwd());
   const targetLabel = targetIsRemote
     ? ctx.environmentName ?? describeAdapterExecutionTarget(target)
diff --git a/server/src/__tests__/adapter-registry.test.ts b/server/src/__tests__/adapter-registry.test.ts
index 341079db14..b917d045b3 100644
--- a/server/src/__tests__/adapter-registry.test.ts
+++ b/server/src/__tests__/adapter-registry.test.ts
@@ -313,6 +313,25 @@ describe("server adapter registry", () => {
     });
   });
 
+  it("verifies the Claude harness on a computer after checking its platform", async () => {
+    const calls: string[] = [];
+    const result = await requireServerAdapter("paperclip_runner").testEnvironment({
+      companyId: "company-1", adapterType: "paperclip_runner",
+      config: { provider: "acpx", acpxAgent: "claude", model: "claude-sonnet-4-6", env: { ANTHROPIC_API_KEY: "test-key" } },
+      executionTarget: { kind: "remote", transport: "computer", remoteCwd: "/workspace", resourceAuthority: { computerId: "computer" },
+        runner: { execute: async (input: { command: string; args?: string[] }) => {
+          calls.push(input.command);
+          const stdout = input.command === "claude" ? JSON.stringify({ type: "result", result: "hello", usage: { input_tokens: 1, output_tokens: 1 } })
+            : input.args?.some(arg => arg.includes("uname -s")) ? "Linux\nx86_64\n" : "";
+          return { exitCode: 0, timedOut: false, stdout, stderr: "", signal: null, pid: null, startedAt: new Date().toISOString() };
+        } },
+      } as never,
+    });
+    expect(calls).toContain("claude");
+    expect(result.checks).toContainEqual(expect.objectContaining({ code: "claude_hello_probe_passed", level: "info" }));
+    expect(result.checks.some(check => check.level === "error")).toBe(false);
+  });
+
   it.each([true, false])("checks actual local ACPX installation readiness (%s)", async (ready) => {
     const probe = vi.mocked(probeAcpxClaudeInstallation);
     if (ready) probe.mockResolvedValueOnce(undefined);
diff --git a/server/src/__tests__/claude-local-adapter-environment.test.ts b/server/src/__tests__/claude-local-adapter-environment.test.ts
index 055e66d9ea..50f2247d60 100644
--- a/server/src/__tests__/claude-local-adapter-environment.test.ts
+++ b/server/src/__tests__/claude-local-adapter-environment.test.ts
@@ -298,7 +298,7 @@ describe("claude_local environment diagnostics", () => {
     expect(result.checks.some((check) => check.code === "claude_cwd_invalid")).toBe(false);
   });
 
-  it("uses full permission bypass for sandbox hello probes", async () => {
+  it.each(["sandbox", "computer"] as const)("uses full permission bypass for %s hello probes", async (transport) => {
     const executeCalls: Array<{ command: string; args?: string[]; env?: Record<string, string> }> = [];
 
     const result = await testEnvironment({
@@ -310,11 +310,12 @@ describe("claude_local environment diagnostics", () => {
       },
       executionTarget: {
         kind: "remote",
-        transport: "sandbox",
+        transport,
+        resourceAuthority: { computerId: "probe-computer" },
         providerKey: "cloudflare",
         remoteCwd: "/workspace/paperclip",
         runner: {
-          execute: async (input) => {
+          execute: async (input: { command: string; args?: string[]; env?: Record<string, string> }) => {
             executeCalls.push({ command: input.command, args: input.args, env: input.env });
             if (input.command === "claude") {
               return {
@@ -345,7 +346,7 @@ describe("claude_local environment diagnostics", () => {
             };
           },
         },
-      },
+      } as never,
       environmentName: "QA Cloudflare",
     });
 
diff --git a/server/src/adapters/registry.ts b/server/src/adapters/registry.ts
index 54b72aa3bd..c4fb1b1c63 100644
--- a/server/src/adapters/registry.ts
+++ b/server/src/adapters/registry.ts
@@ -432,6 +432,12 @@ const paperclipRunnerAdapter: ServerAdapterModule = {
           if (!((os === "Linux" && arch === "x86_64") || (os === "Darwin" && (arch === "arm64" || (profile.acpxAgent !== "grok" && arch === "x86_64"))))) {
             throw new Error(`ACPX ${profile.acpxAgent} requires a qualified Linux x64 or macOS architecture.`);
           }
+          if (target.transport === "computer" && profile.acpxAgent === "claude") {
+            const hello = await claudeTestEnvironment({ ...context, adapterType: "claude_local",
+              config: { ...context.config, engine: "cli", model: profile.model,
+                dangerouslySkipPermissions: context.config.acpxPermissionMode === "approve-all" } });
+            return { ...hello, adapterType: "paperclip_runner" };
+          }
           return {
             adapterType: "paperclip_runner", status: "warn" as const, testedAt: new Date().toISOString(),
             checks: [{ code: "acpx_remote_runtime_unverified", level: "warn" as const,
diff --git a/server/src/services/agent-environment-test.ts b/server/src/services/agent-environment-test.ts
index ae26b719ba..5543a4bb83 100644
--- a/server/src/services/agent-environment-test.ts
+++ b/server/src/services/agent-environment-test.ts
@@ -361,7 +361,11 @@ export function agentEnvironmentTestService(db: Db, pluginWorkerManager?: Plugin
       executionTarget: target,
       environmentName: environment.name,
       fallbackChecks: [],
-      sandboxIdentityCheck: buildSandboxIdentityCheck({
+      sandboxIdentityCheck: environment.driver === "computer" ? {
+        code: "computer_test_identity", level: "info",
+        message: `Environment test ran on "${environment.name}" with a bounded computer owner.`,
+        detail: `paperclipLeaseId=${leaseRecord.lease.id}; ownerId=${leaseRecord.lease.providerLeaseId}`,
+      } : buildSandboxIdentityCheck({
         environmentName: environment.name,
         lease: leaseRecord.lease,
       }),
@@ -433,7 +437,7 @@ export function agentEnvironmentTestService(db: Db, pluginWorkerManager?: Plugin
 
   // The environment drivers the adapter Test route accepts. A local, SSH, or
   // sandbox environment can host a probe; a plugin environment cannot.
-  const ADAPTER_TEST_ALLOWED_ENVIRONMENT_DRIVERS = ["local", "ssh", "sandbox"];
+  const ADAPTER_TEST_ALLOWED_ENVIRONMENT_DRIVERS = ["local", "ssh", "sandbox", "computer"];
 
   // The fail-closed tenant-binding guard for the adapter Test route. A caller
   // may name any instance environment by id, so the route must reject an
diff --git a/server/src/services/computer-environment-driver.test.ts b/server/src/services/computer-environment-driver.test.ts
new file mode 100644
index 0000000000..f3c3dd6cd2
--- /dev/null
+++ b/server/src/services/computer-environment-driver.test.ts
@@ -0,0 +1,24 @@
+import { describe, expect, it, vi } from "vitest";
+import { createComputerEnvironmentDriver } from "./computer-environment-driver.js";
+
+const state = vi.hoisted(() => {
+  const binding = { owner: { computerId: "computer", ownerId: "owner", generation: 1 },
+    listenerPort: 43127, remoteCwd: "/remote/workspace", placementId: "placement", agentHome: "/remote/home" };
+  return { admit: vi.fn(async () => binding), admitProbe: vi.fn(async () => binding),
+    retire: vi.fn(async () => ({ retired: true })), acquireLease: vi.fn(async (input: unknown) => input) };
+});
+vi.mock("../modules/computers/index.js", () => ({ computerService: () => state }));
+vi.mock("./environments.js", () => ({ environmentService: () => state }));
+vi.mock("./instance-settings.js", () => ({ instanceSettingsService: () => ({ getExperimental: async () => ({ enableBoatEnvironments: true }) }) }));
+
+describe("computer environment probe ownership", () => {
+  it("admits a bounded probe without fabricating a heartbeat run", async () => {
+    const db = { update: () => ({ set: () => ({ where: async () => undefined }) }) };
+    const driver = createComputerEnvironmentDriver(db as never);
+    await driver.acquireRunLease({ companyId: "company", agentId: "agent", heartbeatRunId: null,
+      environment: { id: "environment", config: {} }, adapterType: "paperclip_runner" } as never);
+    expect(state.admit).not.toHaveBeenCalled();
+    expect(state.admitProbe).toHaveBeenCalledWith(expect.objectContaining({ companyId: "company", environmentId: "environment", agentId: "agent", probeId: expect.any(String) }));
+    expect(state.acquireLease).toHaveBeenCalledWith(expect.objectContaining({ heartbeatRunId: null, providerLeaseId: "owner", metadata: expect.objectContaining({ driver: "computer", computerOwner: { computerId: "computer", ownerId: "owner", generation: 1 } }) }));
+  });
+});
diff --git a/server/src/services/computer-environment-driver.ts b/server/src/services/computer-environment-driver.ts
index 1a1fea64e7..fba7139f1b 100644
--- a/server/src/services/computer-environment-driver.ts
+++ b/server/src/services/computer-environment-driver.ts
@@ -3,7 +3,7 @@ import { environmentLeases } from "@paperclipai/db";
 import { remoteTerminationReceipt } from "./remote-execution-termination.js";
 import { instanceSettingsService } from "./instance-settings.js";
 import { resolvePaperclipRunnerIdleTimeoutMs } from "@paperclipai/adapter-utils";
-import { createHash } from "node:crypto";
+import { createHash, randomUUID } from "node:crypto";
 import type { Db } from "@paperclipai/db";
 import type { EnvironmentLease } from "@paperclipai/shared";
 import type { AdapterComputerExecutionTarget, EffectiveExecutionCapabilities } from "@paperclipai/adapter-utils/execution-target";
@@ -45,11 +45,13 @@ export function createComputerEnvironmentDriver(db: Db): EnvironmentRuntimeDrive
     driver: "computer",
     async acquireRunLease(input) {
       if (!(await instanceSettingsService(db).getExperimental()).enableBoatEnvironments) throw new Error("boat_environments_disabled");
-      if (!input.agentId || !input.heartbeatRunId) throw new Error("computer_agent_run_required");
+      if (!input.agentId) throw new Error("computer_agent_required");
       const idleTimeoutMs = resolvePaperclipRunnerIdleTimeoutMs(input.environment.config.runnerIdleTimeoutMs);
-      const binding = await computers.admit({ companyId: input.companyId, environmentId: input.environment.id,
+      const binding = input.heartbeatRunId ? await computers.admit({ companyId: input.companyId, environmentId: input.environment.id,
         agentId: input.agentId, runId: input.heartbeatRunId, idleTimeoutMs,
-        sessionKey: createHash("sha256").update(JSON.stringify([input.agentId, input.executionWorkspaceId ?? input.issueId, input.adapterType])).digest("hex") });
+        sessionKey: createHash("sha256").update(JSON.stringify([input.agentId, input.executionWorkspaceId ?? input.issueId, input.adapterType])).digest("hex") })
+        : await computers.admitProbe({ companyId: input.companyId, environmentId: input.environment.id,
+          agentId: input.agentId, probeId: randomUUID(), idleTimeoutMs });
       try {
         // The durable owner advanced generation; prior retained bookkeeping no
         // longer owns the process and must not be reaped as an allocation.