Add an explicit --network flag for read-only tasks

[naniastudios]

Title

Add an explicit network flag for read-only mandates

Problem

In Codex CLI 0.147.0, the read-only sandbox has no network access. As a
result, read-only mandates that need to reach the network fail with a
misleading DNS error. The existing --write flag cannot express a mandate
that needs network access but must not write to the workspace.

Solution

Add an explicit --network boolean flag, separate from --write. When
--network is selected, task startup uses workspace-write and explicitly
enables sandbox_workspace_write.network_access; --write remains
independent, and the default behavior is unchanged when neither flag is
provided.

Verification

• Red: before the patch, a task started without --network uses the
  read-only sandbox and a network probe fails with the sandbox's DNS error.
• Green: after the patch, a task started with --network uses
  workspace-write with network access enabled and the same network probe
  succeeds; a task without --network remains network-disabled.
• node --check passes for scripts/codex-companion.mjs and
  scripts/lib/codex.mjs.

[sylvesterkaczmarek]

This makes --network violate the read-only guarantee it is intended to preserve. When network=true and write=false, executeTaskRun() selects the workspace-write sandbox, and the added config only enables network access inside that sandbox; it does not remove workspace write permission. A read-only task that asks for network can therefore modify the workspace. I would not use workspace-write as the transport for this flag unless the permission profile explicitly denies writes. If Codex 0.147.0 cannot express read-only plus network directly, this should fail closed or use a request-scoped filesystem profile that keeps the workspace read-only while enabling network. A regression should attempt an actual workspace write under --network without --write and require it to fail.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Preserve read-only isolation when enabling network

For every task --network invocation without --write, this selects workspace-write, so the agent can modify the repository despite the flag being intended for mandates that “must not write.” Because thread startup also uses approvalPolicy: "never", those writes are not gated by an approval prompt, and the job is still recorded as write: false; use a sandbox/policy that combines read-only filesystem access with networking, or reject this mode until one is available.

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