## What changed
- Add a multi-turn scenario covering `request_user_input_async`, continued work while awaiting an answer, and delivery of the answer into the active turn.
- Add a scenario covering plugin configuration reload in an existing thread, including discovery and use of newly installed skills and MCP tools across turns.
- Render explicit tool output names and namespaces in context snapshots, with a regression test ensuring outputs do not inherit metadata from their calls.
GitOrigin-RevId: 64fca8cb51a3a697fa84bf444ce55b8408961ab5
## What changed
- Use literal model instruction templates and the standard fallback prompt, ignoring legacy personality variables. Retain catalog decoding compatibility and report `supports_personality` as `false` for generated model presets.
- Stop emitting `<personality_spec>` developer messages and assigning an implicit Pragmatic configuration default.
- Filter Friendly/Pragmatic overrides from TUI requests while preserving explicit `personality = "none"`. With `features.personality` enabled, this opt-out still strips the model's personality section.
- Refresh inherited model instructions for agent roles only when the personality opt-out changes, preserving custom instructions.
## Testing
Update coverage for literal legacy templates, deprecated overrides on turn start and resume, role instruction refresh, and forwarding the explicit opt-out through thread start, resume, and fork requests.
GitOrigin-RevId: 1391db4e565e010569f0885f80013d1f86b45825
## What changed
Add two integration scenarios for `gpt-6-astra` that snapshot request history and settings:
- A multi-turn conversation with local and plugin skills, remote compaction, and a follow-up containing an image.
- A release check combining direct collaboration calls with Code Mode shell commands, MCP calls, image viewing, and patch application, including reading back the edited file.
GitOrigin-RevId: 9b8a48a817c3dba4b139d1b0d015e8084dcb219b
## What changed
- Use one renderer for captured requests, raw request bodies, and input items. Show only appended items when inputs extend the previous request and settings match; start a new snapshot window otherwise and explain the boundary.
- Add optional request settings and tool inventory deltas. Normalize volatile values with stable labels, preserve multiline content, and fingerprint omitted content so changes remain visible.
- Migrate existing context snapshots and expand compaction snapshots to include request history.
## Testing
Add focused tests for window boundaries, cache key changes, tool deltas, shared item rendering, stable normalization, and fingerprints. Assert that the follow-up request after pre-turn compaction includes the working directory override.
GitOrigin-RevId: 6445b014081208ea432b1f3e2ac835c5e4955cb0
## What changed
Replace the selectable personality templates in the bundled `gpt-5.4` and `gpt-5.5` definitions with fixed friendly instructions. Personality selection becomes unavailable for these models in the TUI, and submitted turns omit the personality override. Remove personality overrides from Python SDK examples and the walkthrough notebook.
## Testing
Update core and TUI tests to cover fixed friendly instructions, ignored pragmatic updates, unavailable personality selection, and omitted turn overrides. Preserve coverage for selectable personalities in legacy catalogs, and add coverage for resumed legacy sessions and explicit empty instruction overrides.
GitOrigin-RevId: 869a71445584272405fcbd1325efc31c224808c8
## What changed
Remove `thread/rollback`, its request and response types, generated bindings, and the core `Op::ThreadRollback` operation. Requests now follow the generic unknown-method rejection path. Document `thread/revert` as the alternative for paginated threads.
Keep historical `ThreadRolledBack` markers and legacy error deserialization so existing rollouts remain compatible with replay and migration.
## Testing
Adapt retained-context and Guardian history tests to append legacy rollback markers and resume threads, preserving coverage of surviving instructions, answers, and review history.
GitOrigin-RevId: b3da1becdf86b1869275aacb0ffc2817cee5af2e
## What changed
- Accept `disabledPluginIds` in `thread/settings/update` and `turn/start`. A supplied list replaces the saved selection; omission or `null` preserves it, and `[]` clears it.
- Return the selection in thread start, resume, and fork responses and `thread/settings/updated` notifications. Update generated schemas and client types.
- Restore disabled plugin IDs from the history retained at the requested fork boundary, preserving explicit overrides.
The selection persists across resume but does not yet filter plugin capabilities.
## Testing
Add coverage for replacing, preserving, and clearing selections without inference; turn-start notifications; resume; and fork boundaries across legacy and paginated history, with loaded and restarted parents. Add a core regression test for history restoration and explicit clearing.
GitOrigin-RevId: 654a8c2a0527228d422c0dd4919228447e2663db
## What changed
Carry optional `available_access_programs` metadata through model information, presets, caches, and the TUI, and expose it as `availableAccessPrograms` in app-server `model/list` responses. Update the generated JSON schemas, TypeScript types, and Python models.
Preserve the distinction between missing metadata and an empty `cyber` list. Ignore unknown cyber program names when reading the catalog so new server programs do not prevent older clients from loading it. Discovery metadata does not grant access; inference still enforces authorization.
## Testing
Add coverage for absent, null, empty, and populated metadata, unknown program names, and app-server serialization. Extend cache tests and verify that online refreshes persist changed access metadata even when the catalog ETag stays unchanged.
GitOrigin-RevId: b3ef5805c1c61b8d64b9b896c9c0a79120143667
## What changed
After resolving startup configuration and model defaults, reject `features.token_budget.use_history_notes_extension` when the starting model lacks `supports_experimental_context`. Return an error directing users to disable the option or select a compatible model.
## Testing
Add startup coverage for explicit configuration and model defaults, verifying rejection for unsupported models and successful activation for supported models and standalone token budgets. Update history-notes test fixtures to declare experimental context support.
GitOrigin-RevId: abf1a024efc5acf97cfc858fbb93821363769dc0
## Why
A yielded code mode cell can emit a notification after the session switches models. Its output should retain the originating model's truncation budget instead of using the receiving model's budget.
## What changed
Carry the cell's output token limit, including the serialization allowance, through notification dispatch and attach it as `history_truncation_token_limit` metadata. Allow `inject_if_running` to accept response item envelopes so queued notifications preserve this metadata in history and rollouts.
## Testing
Add regression coverage for delayed notifications across a model switch, verifying per-cell truncation budgets, full notification text in raw events, and persisted rollout metadata. Add a task-completion test that checks notification budgets are preserved alongside queued user input.
GitOrigin-RevId: 28380a039a6d41ea324401fcf1f611d81a279477
## Why
A code-mode cell can outlive its turn. Nested tool calls dispatched during a later turn need the original step's tools and context, while approval handling must still work across that turn boundary.
## What changed
- Retain each cell's originating `StepContext` for nested tool dispatch and cancel queued calls whose context has been released.
- Keep MCP approval metadata available for the lifetime of the running invocation, keyed by server and call ID.
- Apply Guardian denial accounting and interruption to the active turn, including reviews from an earlier cell.
- Carry `turn_id` in legacy MCP begin/end events so history reconstruction and rollout migration assign late completions to their original turn. Preserve the current-turn fallback for older records without it.
## Testing
Add regression coverage for originating tool selection across turns, callback and metadata cleanup, delayed MCP elicitation review, Guardian interruption of the active turn, and late MCP completion attribution with legacy compatibility.
GitOrigin-RevId: 4533379aae6e4ecb4aabe5a25e4aca5d65385d76
## Why
ChatGPT derives Responses cache affinity from the `session-id` header. Ephemeral forks need to reuse their parent's cache routing while retaining their own session and thread identities.
## What changed
- Inherit the parent session ID as the `prompt_cache_key` for ephemeral root forks.
- Use the prompt cache key for root-agent Responses `session-id` headers, including WebSocket handshakes. Preserve the actual session identity in turn metadata and leave non-root-agent routing unchanged.
- Keep enabled goal tool definitions visible on ephemeral threads, but reject execution with `Goal tools require a persistent thread.` and disable automatic goal continuation without persistent state.
## Testing
Add regression coverage for inherited cache routing with distinct fork identities, matching parent and fork tool definitions, WebSocket session headers, and rejection of ephemeral goal tool execution.
GitOrigin-RevId: d235e97630068b27f7ebd562dd23ac6266ebc1b9
## Why
Enterprise MCP authorization must remain controlled by host, user, or managed configuration. Project settings and plugin declarations must not redirect enterprise credentials or downgrade the selected authentication mode.
## What changed
- Add `auth = "ema_auth"`, shared `mcp_enterprise_managed_auth` IdP configuration, and per-plugin enterprise registration settings.
- Require enterprise registrations to come from one non-project configuration layer, preserve managed IdP precedence, and reject project overrides that change authorization or re-enable disabled enterprise servers.
- Add the disabled-by-default `use_xaa` feature flag and require non-project opt-in or a managed requirement.
- Reject plugin declarations that select `ema_auth`. Keep EMA connections unsupported and block ordinary MCP OAuth login and credential fallback for this mode.
- Extend the configuration schema and serialization for the new settings.
## Testing
Add coverage for IdP precedence, incomplete registrations, alternate credential validation, project-only opt-in, plugin self-declaration rejection, configuration round-tripping, and trusted-project attempts to downgrade enterprise auth to OAuth or ChatGPT auth.
GitOrigin-RevId: f193bdfda74208c98e496a23bf2916955b131a1c
## What changed
- Expose `ThreadInstructionsProvider` through `StartThreadOptions`. Load its snapshot at startup and model-request boundaries, composing it after global instructions and before repository instructions. Empty or blank output clears only the thread contribution.
- Reject thread instructions exceeding 10,000 estimated tokens independently of the repository instruction budget. Allow host-provided instructions without a filesystem source and rename the shared future type to `LoadInstructionsFuture`.
- Retain the provider across warm resumes; require hosts to supply it again for cold resumes and offline forks. Live forks and subagents inherit applied snapshots without inheriting the source thread's provider, including when the parent is unloaded during setup or reload.
- Include thread instructions in guardian reviewer inheritance and reuse decisions.
## Testing
Add coverage for composition and clearing, refresh within an active turn, size rejection before sampling, cancellation-safe refresh, fork and resume behavior, parent eviction, and reviewer reuse invalidation.
GitOrigin-RevId: 7be9a523cbbfd67704067dfd526188dad89a3c88
## Why
Running root threads retained their startup global instructions, so edits to global `AGENTS.md` files did not take effect during an active session.
## What changed
- Reload global instructions when capturing model-request context, including after tools within the same turn. Apply changes without repeating unchanged instructions or rediscovering repository instructions when the environment and trust level are unchanged.
- Preserve the last successful global instructions on read failures, suppress recurring warnings until recovery, and clear instructions when their source is removed or blank.
- Serialize refreshes and allow cancellation without blocking subsequent requests.
- Give new subagents the parent's applied instruction snapshot and update Guardian reviewer reuse to account for refreshed instructions.
## Testing
Add regression coverage for live edits and removal, read failures and recovery, warning suppression, cancellation, subagent inheritance, and Guardian reviewer reuse. Update resume, fork, and compaction tests to verify refreshed instructions.
GitOrigin-RevId: f7e9b399740fa4f45e482c070f6e901ee7cf85cd
## Why
Delegated usage should retain the trigger of the turn that initiated it, including composer input and scheduled automation.
## What changed
Propagate `turn_trigger` through agent spawning and follow-up messages in both multi-agent tool implementations. Apply the supplied trigger when pending mailbox work starts a new turn.
## Testing
Extend tests to verify trigger propagation to spawned and nested agents, updated triggers on reused agents and peer follow-ups, and preservation of the active turn's trigger when steering.
GitOrigin-RevId: e8fea208587c633fec7cb3f1c0815ff91d1a44e5
## What changed
- Apply `disabled_plugin_ids` to plugin skills, recommendations, hooks, and MCP servers without modifying shared plugin state.
- Activate selection changes when the next task starts, keeping pending settings from changing the active runtime.
- Hide app tools contributed only by disabled plugins from model tool catalogs and search. Preserve connectors shared with enabled plugins and existing direct Apps RPC behavior.
- Include plugin identity in MCP approval keys and use that identity when persisting plugin tool approvals.
## Testing
Add regression coverage for disabling and re-enabling plugin skills and tools, deferred activation of settings, shared connector ownership, selected plugin servers, executor hooks, and plugin-specific approval keys and persistence.
GitOrigin-RevId: 1153ff6aa7ab6953d50e838da05203904ecd2956
## What changed
- Support `model_provider` and `model_providers` in managed requirements. Required selection overrides local and session configuration; each required provider definition replaces the corresponding local entry, including its authentication and headers.
- Merge provider requirement fragments before validation, preserving source-relative `auth.cwd` paths. Reject invalid cloud provider definitions before replacing the cached bundle, including unsupported Bedrock overrides.
- Expose `modelProvider` and `modelProviders` through the configuration requirements API and generated schemas. Reject writes to managed provider settings and omit their local origins, including for provider IDs containing dots.
## Testing
Add tests for requirement precedence, authentication fragment merging, path resolution, cloud cache preservation, and read-only configuration RPCs. Integration tests verify that model discovery and inference use the required gateway and ChatGPT authentication without leaking local headers, and that provider requirements survive configuration rebuilds.
GitOrigin-RevId: d1448604d4ef5662ebb5df7b693712d3b8ad6d54
## Why
An enabled shared analytics client could override a thread's explicit opt-out.
Delegated threads also emitted initialization events through the parent's client,
bypassing the child's analytics setting.
## What changed
- Use a disabled analytics client when `config.analytics_enabled` is `Some(false)`,
without disabling analytics for sibling threads or overriding a disabled host client.
- Emit delegated thread initialization events through the child's analytics client.
- Expose the effective analytics state through `CodexThread::analytics_enabled()`.
## Testing
Add regression tests for explicit and unset thread settings with enabled, disabled,
and absent shared clients, plus delegated child opt-outs with an enabled parent.
Update compaction and rollout-budget rollback tests to wait for thread idle after
turn completion and fail immediately on rollback errors.
GitOrigin-RevId: 547852909af1a6822b95c0bcd2336b0d6bc7aad1
## Why
The offline sandbox's non-loopback firewall block covered only outbound traffic. Add a matching inbound block for the offline sandbox user.
## What changed
- Configure an inbound firewall rule scoped to the offline user's SID, blocking all protocols and ports for non-loopback remote addresses.
- Make firewall rule direction explicit while preserving the existing outbound rules.
- Remove the new inbound rule during uninstall.
## Testing
Extend the elevated Windows sandbox integration test to inspect effective inbound and outbound rules, asserting their uniqueness, direction, block action, enabled state, profiles, address and port filters, protocol, and user scope.
GitOrigin-RevId: cbc1ca0d8d08a31fc53da5ad5be6ee5d51afa63d
## What changed
Add an optional `analytics_enabled` boolean to `x-codex-turn-metadata`, sourced from the session's selected analytics client. It reports collection state independently of event eligibility or delivery and is omitted without initialized session analytics context.
Reserve `analytics_enabled` so configured or client-supplied metadata cannot override it. Continue accepting existing configurations containing this key while filtering their values from request metadata.
## Testing
Add coverage for the selected analytics client's state taking precedence over turn configuration, reserved-key filtering and compatibility, enabled state in HTTP headers and body metadata, and disabled state in WebSocket prewarm and turn requests.
GitOrigin-RevId: d95375c5ebc27e9d763a7e1a98687a27e4a8d99c
## Why
Persisted turn-start events lack the originating root turn ID, so they cannot directly associate child turns with the root turn that initiated them.
## What changed
- Add optional `root_turn_id` to `TurnStartedEvent`. Use the inherited root turn ID when available, otherwise the turn's own ID.
- Centralize turn-start emission for regular turns, shell commands, and manual compaction so they record attribution consistently.
- Carry attribution into `ThreadHistoryTurnChange` when processing turn-start events and retain it through completion in the history builder.
- Keep older records compatible by defaulting missing attribution to `None`.
## Testing
Add coverage for root and child turn attribution, persistence when tool collisions fail a turn before sampling, history change propagation, and deserialization of older turn-start records.
GitOrigin-RevId: 54a80b828ca7d1c4c19f13d468c01d052e1b9130
## Why
Background commands can outlive their launching turn. Their network reviews need the original execution environment even when current turn settings change, and pending reviews must stop when the execution is cancelled.
## What changed
- Capture the execution's environment snapshot for Guardian network reviews while continuing to use current review settings.
- Deny requests from already cancelled executions before checking session host grants, and resolve pending approvals as denied when execution cancellation interrupts review.
- Preserve accepted review results and session grants when cancellation happens after acceptance.
## Testing
Add regression coverage for same-turn and later-turn settings changes, the original review working directory, cancellation before and after review acceptance, late callbacks, background process termination, and reuse of accepted session grants by new executions.
GitOrigin-RevId: 29487488da9ab43700ba6684c61eea86f30a03a8
## Why
Model changes during a turn and catalog refreshes can leave Guardian reviews using settings or metadata that do not match the action being reviewed.
## What changed
- Use the action's captured model, reasoning effort, reasoning summary, and personality when configuring reviews.
- Preserve captured model metadata when falling back to the parent model, while resolving a separate reviewer against the current catalog on each attempt.
- Evaluate live managed review requirements against the action's model and use its metadata for computer-use review behavior.
- Include personality in the review session reuse key so personality changes invalidate cached sessions.
## Testing
Add regression coverage for delayed and new actions across model changes and catalog refreshes, required-review routing, and session reuse when policy or personality changes. Extend integration tests to cover reviewer reuse across parent model changes and verify that interrupted reviews cannot execute commands after a delayed approval arrives.
GitOrigin-RevId: 5b434568e113e44bf7177780f2ae13192b55e942
## Why
Extension-owned HTTP MCP servers previously inherited the default protocol mode. Extensions need to select a mode for their own server independently of other HTTP servers.
## What changed
- Add `McpServerContribution::SetWithProtocolMode` and re-export `McpProtocolMode` through the extension API.
- Carry the winning registration's protocol override through catalog resolution and materialization, and apply it to Streamable HTTP connections.
- Preserve existing defaults when no override is present. Selecting a protocol mode does not grant host-owned Apps cache access or environment authority.
## Testing
Add coverage for registration precedence and materialization, and extend cache isolation tests to cover explicit protocol selection. Add an integration test verifying that extension servers can select either the legacy or newer protocol while other HTTP servers retain the default mode.
GitOrigin-RevId: 606cecc03094a93258ffc433849f575020b81473
## Why
Transcript limits could shorten user instructions or omit later messages before Guardian evaluated the complete request budget, losing restrictions or prior approvals even when they would fit.
## What changed
- Keep user messages and manual approvals complete and in source order through transcript collection and retention.
- Preserve historical instructions while synchronous review can still compact history. If the final request still cannot fit, discard optional evidence before shortening older historical entries with truncation markers, preserving later restrictions where possible.
- Warn that shortened instructions and approvals are incomplete and that missing evidence does not authorize actions.
- Let asynchronous review defer to synchronous review when complete instructions exceed its budget.
## Testing
Add coverage for complete instruction retention, approval and restriction ordering, marked truncation of oversized Unicode text, compaction before truncation, and asynchronous fallback when instructions do not fit.
GitOrigin-RevId: e6159e876231347986b937ee7e07f944b83bfbe6
## Why
Truncating action arguments can leave approval reviewers evaluating incomplete actions. Large actions need complete review input and explicit handling when they exceed the review budget.
## What changed
- Remove action truncation and the fixed synchronous action byte limit. Admit complete actions against the whole-request budget, splitting long text losslessly into bounded transport parts and accounting for their framing.
- Route actions exceeding the asynchronous action budget to synchronous review. Prevent cached scores from covering oversized calls, including expanded approval arguments, while allowing later small actions to recover score reuse.
- Request user approval when optional review exhausts its local input budget. Keep required review and compaction service failures closed to approval, and retire exhausted review sessions.
## Testing
Add coverage for complete large-action delivery, optional user fallback, required-review denial, subsequent review recovery, async overflow through MCP approval routing, and lossless text splitting with budget accounting.
GitOrigin-RevId: 08f06e68a94b2f779480dd6b6cf5bc30b241f6dd
## Why
Codex Apps applies resource MIME filters to each request separately, so continuation requests must include the filter as well as the cursor.
## What changed
Add `McpResourceClient::list_codex_apps_resources` with a required `mime_type` and optional cursor. Send the filter as a top-level `mimeType` parameter in `resources/list` requests and return resources with the next cursor.
Require a host-owned `codex_apps` registration before sending filtered requests, rejecting extension servers that use the same name.
## Testing
Add integration tests covering MIME filters on both pagination requests, returned resource pages, and rejection of extension name collisions without sending a resource request.
GitOrigin-RevId: 4fb33da56c6ef99286564ead7f74b77d8b337335
## Why
MCP tool and connector descriptions were included in required action JSON, consuming review input budget even though they are optional metadata.
## What changed
Move `tool_description` and `connector_description` into an optional, explicitly untrusted `guardian_tool_descriptions` fragment. Limit each description to 400 estimated tokens, escape closing tags, and allow budget enforcement to omit the fragment while retaining the required action JSON. Preserve nested arguments such as `arguments.description` and mention tool descriptions in the budget omission notice.
## Testing
Add regression coverage for oversized descriptions, escaped closing markers, and budget eviction without changing action arguments. Update MCP approval and elicitation tests to verify descriptions appear separately from the action JSON.
GitOrigin-RevId: 30734567c2ebc4b180110276c83d79ddb315ceab
## Why
Switching accounts could reuse a Responses WebSocket connection and incremental response state belonging to the previous account.
## What changed
Track auth ownership for cached WebSocket sessions and reconnect when it changes, including across turns. Clear incremental response state and `x-codex-turn-state` so the next request sends the full input with fresh routing state. Apply the same connection handling to prewarm requests and build request metadata after checking ownership.
## Testing
Add a regression test for account switches within a turn and between turns. Verify new account credentials on reconnect, full input without `previous_response_id` or stale routing state after the switch, and subsequent connection and incremental response reuse.
GitOrigin-RevId: 83b0636c0afec8b21b5d837a9937db32fb448237
## Why
Pre-turn compaction runs before incoming input is recorded, so failures could leave an accepted prompt out of conversation history. Reporting the error before prompt hooks finish also lets clients steer follow-up input into a turn still preserving its prompt.
## What changed
Record input and run prompt hooks on every pre-turn compaction failure. Defer local and remote compaction error events to `run_turn`, after prompt preservation completes, while retaining the remote error prefix.
## Testing
Extend the remote compaction output-validation test to trigger automatic compaction and assert that the prompt is emitted before the error, saved exactly once, and followed by no additional model request. Retain the assertion that usage is recorded for invalid compaction output.
GitOrigin-RevId: ab7ccb259836c084173e0e81dbbd4c610e95a6c8
## Why
Transient rate limits can end automatic approval reviews prematurely, and review failures currently report high risk even when no assessment completed.
## What changed
- Retry rate limits and recoverable exhausted-stream errors, while excluding non-transient HTTP failures.
- Preserve server retry delays after stream retries are exhausted and honor them within the review deadline. Scope retry advice to the current turn so reused sessions cannot apply stale delays.
- Keep failed reviews denied, but leave risk and authorization unset and explain that the review could not complete without declaring the action unsafe.
## Testing
Add an integration test covering rate-limit recovery through approval and tool execution, asserting that the action executes exactly once after approval. Update failure assertions to check absent assessment fields and the review-failure explanation.
GitOrigin-RevId: 1163cfde35c6b8eb23b6f24f1f24461b86ded838
## Why
Reused call IDs, ambiguous exec/wait associations, and missing history can make tool-call completeness claims unreliable. Truncating one cell's recorded calls should also preserve completeness for unrelated cells.
## What changed
- Track observed call and runtime cell IDs with bounded memory, including call IDs from initial history, and withhold completeness when evidence is missing or ambiguous.
- Validate exec/wait input-output associations and keep invalidated completeness from returning on retries. Withhold wait completeness after resume or fork, where runtime cell IDs can be reused.
- Keep truncation markers and omission counts local to each output, clearing completeness across the affected cell while preserving unrelated cells within the metadata budget.
- Refresh recording enablement from runtime configuration without changing execution features, and preserve the live recorder during legacy configuration reloads.
## Testing
Add regression coverage for reused IDs, compaction, resumed waits, mismatched wrappers, runtime recording changes, and metadata budgeting that preserves unrelated complete calls.
GitOrigin-RevId: 0bc85964bee079879620ec0664eea530a13b61fb
## What changed
Add the default-off `api_key_model_discovery` feature and expose it through app-server experimental feature enablement, respecting user configuration overrides.
When enabled, fetch OpenAI API-key model metadata from the Codex backend, honoring explicit provider base URLs. Treat remote catalogs containing visible models as authoritative. When disabled at startup, skip discovery requests and cached catalogs and retain bundled models.
## Testing
Add coverage for feature enablement and user overrides, cached catalogs across sessions, provider routing, and API-key `model/list` results. Extend coverage for remote instructions and auth-specific cache isolation.
GitOrigin-RevId: 4b189c37c615a7f808cb6ff5f0858a9a55f36ebc
## Why
Forked threads reported `startup`, causing startup hooks to run again even when their context was inherited from the parent. Resuming with supplied history also reported `startup` instead of `resume`.
## What changed
- Add `fork` as a `SessionStart` source and expose it in the hook input schema.
- Report `fork` for histories with a fork parent and `resume` for supplied histories without one.
- Continue dispatching `SubagentStart` for spawned subagents with either fresh or forked context.
## Testing
Add regression coverage for fork hook matching without duplicate startup context, resume hooks with supplied history, and `SubagentStart` context injection for fresh and forked subagents.
GitOrigin-RevId: 5ac1ae4ab8adcbbbceb8cb0ffb9b32b6402c585b
## What changed
- Add host-recorded `tool_result_metadata` snapshots with size limits, redacted debug output, and protection against deserialization from untrusted input. MCP capture remains disabled.
- Preserve accepted metadata across retries and delayed Code Mode results. Shed raw metadata before source evidence, calls, or completion markers when the request budget is exceeded.
- Send raw metadata only to allowed OpenAI and ChatGPT HTTPS endpoints, filtering by the resolved destination for HTTP and WebSocket requests.
- Encode source parse failures as an array entry with type `parse_failed` and an empty ID.
## Testing
Add coverage for metadata bounds and redaction, retained-call updates, budget shedding, disabled MCP capture, and HTTP/WebSocket destination filtering.
GitOrigin-RevId: b1a396323ad0623167cdd9e20ff9453f0d01bbf7
## What changed
- Add `disabled_plugin_ids` to thread startup options, settings overrides, snapshots, and persisted turn contexts. Omitted overrides preserve the current list; an empty list clears it.
- Restore the selection on resume and capture it before truncating history for a fork. Prefer the owning thread's latest settings snapshot, falling back only to the latest turn context so stale history cannot resurrect an older selection.
- Freeze the selection at turn admission and retain compatibility with histories that lack the new fields.
## Testing
Add coverage for owned settings, explicit clears, latest-turn fallback, and legacy snapshots. Extend settings tests to cover plugin selection during runtime restoration and compaction, and verify initial turn persistence without extra settings checkpoints in both history modes.
GitOrigin-RevId: 75ffbff5763cd93cc5ac69d73b08b237f59bc009
## Why
The elevated Windows sandbox requires effective `:root` read access and cannot safely enforce policies that deny reads at the filesystem root.
## What changed
- Validate root read access before elevated setup, service provisioning, and setup refresh, rejecting root-denying globs before expansion.
- Reject filesystem-root deny-read ACL targets after canonicalization and check the opened handle before applying an ACL, so aliases cannot bypass the root guard.
- Read and update deny ACLs through the same handle, and allow an existing deny ACE to be recognized when write access to the ACL is unavailable.
## Testing
Add regression coverage for default root denial, root-denying globs, allowed root reads with narrower deny rules, handle-based root detection, and reading existing deny ACEs without `WRITE_DAC`.
GitOrigin-RevId: b904e7cdbc09ee0147e1818c898b0382b5820c1b
## Why
Hosted Codex Apps shared the `mcp_2026_07_28` protocol setting with other MCP servers, preventing independent protocol selection.
## What changed
- Add `features.codex_apps_mcp_2026_07_28`, disabled by default, for the host-owned HTTP `codex_apps` server. Enabling it attempts 2026-07-28 discovery with Legacy fallback.
- Keep other servers, including third-party registrations with Apps-like names or URLs and local stdio servers, governed by `mcp_2026_07_28`.
- Support the new flag through `experimentalFeature/enablement/set` and refresh protocol settings in existing sessions. Track protocol mode per server when deciding whether to reuse connections.
## Testing
Add coverage for independent feature and protocol selection, hosted event-stream protocol selection, standalone Legacy defaults and discovery fallback, and runtime enablement refreshing an existing app-server thread.
GitOrigin-RevId: 640e8e251f0c45e5f4829cc2b73c3082cf42f715
## Why
Async classifications need to account for the complete request, including parent compaction checkpoints and images, before sending it to the classifier.
## What changed
- Resolve the input allowance from the classifier's model metadata, independently of parent-model context-window overrides.
- Reject requests whose estimated input exceeds that allowance minus a 256-token reserve. Record `input_too_large` and defer to synchronous review without sending the oversized request or dropping evidence to make it fit.
## Testing
Add integration coverage for checkpoint and image budgets, verifying that oversized inputs defer to synchronous review and inputs that fit retain their evidence. Update Guardian context-budget tests to exercise V2 remote compaction.
GitOrigin-RevId: 765060e08d2d5f3028ef5207508d256d4bf8d856
## Why
Initial history replay and rollback before the first turn could clear the reasoning-effort baseline established by startup prewarm, preventing the first request from preserving that baseline when the selected effort changes.
## What changed
Preserve the reasoning-effort pin during history reconstruction. Clear it on rollback only after startup prewarm has been consumed. With reasoning-effort overrides enabled, a prewarmed `medium` baseline remains on the request while a subsequent `high` selection is sent as a `configuration_update`.
## Testing
Add regression coverage for prewarm completing before initial replay on resume and fork. Expand WebSocket tests to cover resumed and forked threads with overrides enabled and disabled, plus rollback before the first turn.
GitOrigin-RevId: 2e2d0e8a06b24f01b717458ca0576d63107c7697
## Why
Review evidence can fit its own limits while exceeding the reviewer context window once history, tools, output format, and reminders are included. Tool continuations can also push an existing review over budget.
## What changed
- Select evidence after tools and turn context are resolved, reserving request overhead and a 256-token margin. Omit optional evidence while preserving required sections, and reject required evidence that cannot fit.
- Keep incoming evidence pending until budget selection succeeds so cancellation and compaction cannot record unselected input in reusable history.
- Check the assembled prompt before sampling, including retries and tool continuations. Retry budget failures with summary compaction once per model step, and retire reviewers whose budgets remain exhausted. Avoid history-resetting token-budget compaction for this recovery.
- Record section costs after budget selection.
## Testing
Add unit and integration coverage for required-evidence rejection, optional-evidence omission, reminder overhead, cancellation safety, incoming-review and tool-continuation compaction, and reviewer retirement after ineffective compaction.
GitOrigin-RevId: 2f7ef191b3f46032d295ad363eb7debf9d7a9684
## Why
Failed environments were omitted from environment context, and `wait_for_environment` returned a generic failure or treated an already-failed environment as unselected. The model needs the failure reason to explain problems such as an empty repository.
## What changed
- Preserve the selected environment and error when startup or configuration fails.
- Include failed status and XML-escaped error details in environment context, and return the reason from `wait_for_environment` for failures detected before or during a wait.
- Limit error details to 256 bytes per environment and 512 bytes total in context, preserving UTF-8 boundaries. Limit wait failure details to 256 bytes.
## Testing
Add coverage for failures before a turn and while waiting, verifying that the model receives the reason and the turn completes. Add unit tests for XML escaping, incremental context updates, clearing errors on recovery, and UTF-8-safe truncation.
GitOrigin-RevId: 093ab9b447c7b3243fbb53b665180db95479f2a7
## Why
Recovering a suspended turn can append a duplicate reasoning effort update when history already ends with a matching trusted update but the runtime has not established its effort pin.
## What changed
Reuse a matching harness-authored `ConfigurationUpdate` at the end of history even when the runtime effort pin is unset.
## Testing
Add a regression test that suspends and recovers a turn without WebSocket prewarming, then verifies the recovered request contains exactly one effort update and retains `high` reasoning effort.
GitOrigin-RevId: 2e49073eb5e8d4fae39a8dc1d9d2b07f77802adb
## Why
Remote compaction already uses the normal Responses API, leaving the legacy `/responses/compact` runner unused.
## What changed
- Remove the legacy runner, endpoint client, request types, analytics variant, and obsolete test helpers and snapshots.
- Move tool-output trimming and its metadata tests into `compact_remote_history` for reuse by remote compaction v2.
- Consolidate retained-history filtering in the v2 implementation and remove redundant `RemoteCompactionV2` settings from tests.
## Testing
Extend the retained-history unit test to explicitly check that hook prompts survive compaction.
GitOrigin-RevId: 999bb1391aa22c3c281d6a96f98817d6c9e46ed9
## What changed
- Route manual and automatic remote compaction through the v2 implementation.
- Retire the `remote_compaction_v2` feature toggle while continuing to advertise it in the model client beta features header.
- Migrate compaction tests from `/responses/compact` to streamed `/responses` requests with `compaction_trigger` items and remove legacy parity coverage.
## Testing
Add streamed compaction coverage for tool search output trimming and session base instruction token estimates. Update app-server tests to verify started/completed notifications for both local and streamed remote compaction.
GitOrigin-RevId: cea392a6166a9b116ff83708fd9126d5546476e4
## Why
Saved model selections can outlive their bundled catalog entries and still need migration guidance.
## What changed
- Remove `gpt-5.2` and `gpt-5.4-mini` from the bundled model catalog.
- Preserve migration from saved `gpt-5.4-mini` selections to `gpt-5.6-luna` when the old model is absent, while respecting catalog-provided migration metadata.
- Update tests and snapshots to use current models or explicit test fixtures, and remove the obsolete prompt fixture.
## Testing
Extend migration tests to cover catalog metadata precedence, saved selections, replacement model and reasoning-effort persistence, acknowledged prompts, and missing or hidden migration targets.
GitOrigin-RevId: 82beea504cc4a15699677c28a61ec0939af3069c
## Why
Switching models can send images from conversation history with `detail: original` to a model that does not support it.
## What changed
Normalize image details on request copies using the receiving model's capabilities. Downgrade `original` to `high` when unsupported, covering user messages and function and custom tool outputs. Preserve stored image details so switching back to a supporting model retains `original`, and continue stripping details for Responses Lite.
## Testing
Expand unit coverage across image detail values and model capabilities. Extend integration coverage for model switches within and between turns, text-only models, and resumed and forked threads, including assertions that persisted tool outputs remain unchanged.
GitOrigin-RevId: 2561651ea74f045e00f708ae53771a41dcd49c94
## Why
Replaying tool outputs under a different model can expand or shrink the history shown to the model if truncation uses the new model's budget.
## What changed
Save the originating history truncation budget on function and custom tool outputs and reuse it during replay, preserving existing tool-specific overrides. Include the existing 20% serialization allowance once, before converting byte budgets to tokens.
Rename the metadata field to `history_truncation_token_limit` while retaining `fallback_token_limit_override` as its serialized name for compatibility.
## Testing
Add regression coverage for resume and fork with different model budgets, including custom tool outputs. Extend unit coverage for existing overrides and byte-budget conversion.
GitOrigin-RevId: a62c8fd3e43198e2252b150fba72f022939c1070