## Why
The migration away from `SandboxPolicy` needs new configs to start from
permissions profiles instead of deriving profiles from legacy sandbox
modes. Existing users can have empty `config.toml` files, and we should
not rewrite user-owned config files that may live in shared
repositories.
This PR introduces built-in profile names so an empty config can resolve
to a canonical `PermissionProfile`, while explicit named `[permissions]`
profiles still behave predictably.
## What changed
- Adds built-in `default_permissions` profile names:
- `:read-only` maps to `PermissionProfile::read_only()`.
- `:workspace` maps to the workspace-write profile, including
project-root metadata carveouts.
- `:danger-no-sandbox` maps to `PermissionProfile::Disabled`, preserving
the distinction between no sandbox and a broad managed sandbox.
- Reserves the `:` prefix for built-in profiles so user-defined
`[permissions]` profiles cannot collide with future built-ins.
- Allows `default_permissions` to reference a built-in profile without
requiring a `[permissions]` table.
- Makes an otherwise empty config choose a built-in profile by
trust/platform context: trusted or untrusted project roots use
`:workspace` when the platform supports that sandbox, while roots
without a trust decision use `:read-only`.
- Keeps legacy `sandbox_mode` configs on the legacy path, and still
rejects user-defined `[permissions]` profiles that omit
`default_permissions` so we do not silently guess among custom profiles.
- Preserves compatibility behavior for implicit defaults: bare
`network.enabled = true` allows runtime network without starting the
managed proxy, explicit profile proxy policy still starts the proxy, and
implicit workspace/add-dir roots keep legacy metadata carveouts.
## Verification
- `cargo test -p codex-core builtin --lib`
- `cargo test -p codex-core profile_network_proxy_config`
- `cargo test -p codex-core
implicit_builtin_workspace_profile_preserves_add_dir_metadata_carveouts`
- `cargo test -p codex-core
permissions_profiles_network_enabled_allows_runtime_network_without_proxy`
- `cargo test -p codex-core
permissions_profiles_proxy_policy_starts_managed_network_proxy`
## Documentation
Public Codex config docs should mention these built-in names when the
`[permissions]` config format is ready to document as stable.
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19900).
* #20041
* #20040
* #20037
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* #20008
* __->__ #19900
## Why
Managed sessions use `NO_PROXY` to keep a small set of destinations on
the direct path by default. The old default also bypassed all IPv4
link-local addresses in `169.254.0.0/16`, which includes metadata
endpoints such as `169.254.169.254`. Because `NO_PROXY` is evaluated by
the client before the request reaches the managed proxy, requests to
that range could skip proxy-side allowlist and local-binding checks
entirely. On hosts where a link-local metadata service is reachable,
that creates a path to sensitive environment metadata or credentials
outside the intended enforcement point.
## What changed
- remove the default IPv4 link-local `169.254.0.0/16` bypass from the
managed proxy environment
- keep the existing loopback and private-network defaults unchanged
- update the regression assertion to lock in the narrower default
## Security impact
Link-local requests now stay on the managed-proxy path by default, so
the proxy can apply configured policy before they reach metadata-style
endpoints or other link-local services.
## Verification
- `cargo test -p codex-network-proxy`
Co-authored-by: Codex <noreply@openai.com>
## Summary
This extends external agent detection/import beyond config artifacts so
Codex can detect recent sessions files from the external agent home and
import them into Codex rollout history.
## What changed
- Added a focused `external_agent_sessions` module for:
- session discovery
- source-record parsing
- rollout construction
- import ledger tracking
- Wired session detection/import into the app-server external agent
config API.
- Added compaction handling so large imported sessions can be resumed
safely before the first follow-up turn.
## Testing
Added coverage for:
- recent-session detection
- custom-title handling
- recency filtering
- dedupe and re-detect-after-source-change behavior
- visible imported turn construction
- backward-compatible import payload deserialization
- end-to-end RPC import flow
- rejection of undetected session paths
- repeat-import behavior
- large-session compaction before first follow-up
Ran:
- `cargo test -p codex-app-server external_agent_config_import_ --test
all`
## Summary
- exit shell mode when `Esc` is pressed while the absorbed `!` is the
only input
- add direct regression coverage plus a composer snapshot for the
restored normal prompt state
## Root cause
Shell mode stores the leading `!` outside the editable textarea. After
typing only `!`, the textarea is empty but the composer is still in bash
mode, so the existing empty-composer `Esc` handling never runs.
## Validation
- `just fmt`
- `cargo test -p codex-tui
bottom_pane::chat_composer::tests::esc_exits_empty_shell_mode`
- `cargo test -p codex-tui
bottom_pane::chat_composer::tests::footer_mode_snapshots`
- `cargo insta pending-snapshots`
`cargo test -p codex-tui` still reports unrelated existing `/status`
snapshot drift in this local environment because the rendered
permissions text is `workspace-write with network access` instead of the
older `read-only` fixture text.
Move local resume and fork cwd filtering to `thread/list` instead of
filtering in the TUI. This makes the `/resume` menu feel slightly faster
to load when working in repos with many historical threads, and
centralizes the cwd filtering in app-server.
**Affected:**
- /resume from inside the TUI.
- codex resume with no session ID and without --last
- codex resume --all
- codex fork with no session ID and without --last
- codex fork --all
**Not affected:**
- codex resume <id>
- codex fork <id>
- codex resume --last
- codex fork --last
Steps to test performance improvement in a real Codex environment:
- Launch `codex resume` using compiled binary in a directory that has
seen many threads.
- Launch `codex resume` using release binary in same directory.
- Observe difference in time-to-full-page as threads load.
