## Why
Private IP destinations always bypassed inherited upstream proxies, preventing their use for private networks reachable through an upstream VPN proxy.
## What changed
- Add `codex exec-server --proxy-private-ips-via-upstream`, also configurable with `CODEX_EXEC_SERVER_PROXY_PRIVATE_IPS_VIA_UPSTREAM=true`. The setting defaults to disabled.
- Allow permitted RFC 1918, carrier-grade NAT, and IPv6 unique-local destinations to use an applicable upstream proxy. Loopback and link-local destinations retain direct routing, and destination access policy still applies.
- Keep connections direct when no valid upstream proxy applies or `allow_upstream_proxy=false`. Errors after selecting an upstream proxy do not trigger a direct retry.
- Rename `ExecServerRuntimePaths` to `ExecServerRuntimeOptions` and carry the routing setting from executor startup into the managed network proxy.
## Testing
Add routing coverage for private address ranges, special-use addresses, and public targets with the option enabled and disabled. Verify that HTTP and CONNECT requests still enforce destination allowlists and denylists, and update the CLI help snapshot.
GitOrigin-RevId: b7c9cc7da0e0f545694a6521b74c9b36b7b92769
## What changed
- Route remote-control enrollment, pairing, client management, and WebSocket connections through the authenticated HTTP client factory. Keep policy denials distinct from authentication failures and wait for policy changes before reconnecting.
- Preserve policy denials through exec-server connection failures so later connection attempts and capability discovery can recover. Keep direct executors running through temporary policy outages while rejecting permanent policy failures.
- Build cached HTTP transports on blocking workers, serialize construction, and retain successful builds after callers time out so request deadlines cover queued construction.
## Testing
Add regression coverage for policy recovery during remote startup, direct registration, accepted WebSocket reconnection, and capability discovery; queued transport construction timeouts; and remote-control WebSocket fallback with invalid custom CA files.
GitOrigin-RevId: c81db18e83de957175bb213d165281ac701089dd
## What changed
- Report `windows_mxc` from native MXC availability on Windows.
- Allow MXC TTY launches and managed networking, using dedicated proxy listeners without requiring a shared-ingress restricting SID.
- Reject MXC custom `argv0` and private-desktop launches, and continue failing closed when native MXC is unavailable.
## Testing
Extend the Windows remote sandbox process-write test to cover MXC with both pipes and ConPTY. Retain coverage for rejecting MXC requests when native support is unavailable.
GitOrigin-RevId: 80c5f319b9066d06b26f0a7eb7119a109e6ebef7
## Why
Allow remote exec servers to connect directly to AWS-hosted registries that
authenticate registry requests and WebSocket handshakes with AWS SigV4.
## What changed
- Add `--remote-transport direct` with SigV4 profile, region, and service
options while keeping Noise as the default transport.
- Register the `direct_jsonrpc_v1` transport and carry plain exec-server
JSON-RPC messages over the authenticated WebSocket.
- Reuse direct registrations across transient disconnects, refresh them after
a `409 Conflict`, and require TLS for non-loopback endpoints.
## Testing
- Cover CLI validation and SigV4 request signing.
- Exercise direct registration, handshake retry behavior, JSON-RPC
interoperability, and process recovery after reconnecting.
GitOrigin-RevId: 0755df330ba3abe5db0a516fdaa49338d9bbe2d2
## Why
Exec-server process and network-policy events need stable attribution to the
launching tool call and executor without recording process payloads.
## What changed
- Add optional `ExecMetadata` to `ExecParams` and propagate the thread and tool
call IDs from unified exec.
- Emit bounded OpenTelemetry events for process start, spawn failure, sandbox
denial, and exit. Correlate them with the launch trace and registry-issued
executor identity while excluding arguments, paths, environment values,
output, and error text.
- Preserve launch attribution across long-running processes and reconnects, and
attach the same metadata to network-policy audit events.
- Keep the protocol backward compatible when metadata is omitted, and prevent
invalid trace headers from inheriting an unrelated active span.
## Testing
Add coverage for metadata serialization and propagation, lifecycle event
fields, trace relationships, reconnect behavior, spawn failures, sandbox
denials, and network-policy attribution.
GitOrigin-RevId: 7aa480a7289c73cb95e2c124c35500bb6f0d5084
## What changed
- Include `environmentInfo` in the exec-server `initialize` response and seed the Rust client's metadata cache from it.
- Fall back to one lazy `environment/info` request when connecting to older servers that omit initialization metadata, then share the cached result across client clones and session recovery.
- Keep app-server `environment/info` requests uncached so they continue to probe the executor.
## Testing
- Cover initialization metadata, the legacy-server fallback, shared caching, accepted WebSocket environments, and repeated uncached app-server probes.
GitOrigin-RevId: 380132d9db183998d73e8c6b0954e4d70c7e8406
## What changed
- Add `EnvironmentManager::from_accepted_websocket` so embedding hosts can
construct a remote environment from an already accepted and authenticated
Axum WebSocket.
- Add `replace_accepted_websocket` to retire the current transport and resume
the same exec-server session on a host-supplied replacement connection.
- Serialize replacement handoffs, reject overlapping replacements, and release
the handoff claim when a replacement attempt is cancelled or fails.
## Testing
- Cover initial connection validation and immediate environment readiness.
- Verify replacement retry behavior and recovery of a running process and its
output after reconnecting.
GitOrigin-RevId: 1f2ab7bcf7b5abbbece5c101801432dc84a8058d
open-matt