Martin Au-Yeung ee46c5ba0e Negotiate MCP extensions per app-server session (#36910) ...

## Why

App-server clients need to advertise structured MCP extension settings, including supported MCP App UI MIME types, rather than only opting into OpenAI form elicitation with a boolean.

## What changed

- Add an `extensions` map to initialize capabilities and preserve `mcpServerOpenaiFormElicitation` as a legacy alias for `openai/form`.
- Capture the declared extension profile when a thread is started, resumed, or forked, propagate it to subagents, and advertise it to downstream MCP servers during initialization.
- Keep the profile stable for the lifetime of the loaded session instead of changing it on later turns or direct tool calls.

## Testing

- Cover extension conversion, downstream MCP initialization, session isolation, legacy form support, and subagent inheritance.

GitOrigin-RevId: fbcedbb74ce788e574b0f884a4c45c4cedb9de54

2026-08-04 15:23:43 +00:00

..

snapshots

Identify agents by name in token budget context (#36815)

2026-08-04 00:51:53 +00:00

abort_tasks.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

additional_context.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

agent_execution.rs

Support leaf models in multi-agent v2 (#36892)

2026-08-04 12:36:14 +00:00

agent_websocket.rs

Include code-mode tool names in Responses Lite metadata (#35271)

2026-07-25 01:05:33 +00:00

agents_md.rs

Consolidate thread startup around StartThreadOptions (#34814)

2026-07-22 19:31:54 +00:00

apply_patch_cli.rs

Render turn diffs for foreign environment paths (#34654)

2026-07-22 02:19:45 +00:00

approvals.rs

Avoid reinjecting permissions after command approvals (#36800)

2026-08-03 21:37:17 +00:00

audio_truncation.rs

Consolidate thread startup around StartThreadOptions (#34814)

2026-07-22 19:31:54 +00:00

auto_review.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

catalog_permission_messages.rs

Use model catalog collaboration mode messages (#36351)

2026-07-31 15:40:52 +00:00

cli_stream.rs

Update models.json (#31684)

2026-07-09 03:40:08 +00:00

client_websockets.rs

Track parent turns for nested Codex requests (#35835)

2026-07-28 21:58:33 +00:00

client.rs

Move skill catalog rendering out of core (#36364)

2026-07-31 17:12:10 +00:00

code_mode_elicitation.rs

code-mode: make all approvals trigger elicitation pause (#31650)

2026-07-08 15:27:04 -07:00

code_mode.rs

Support custom tools in namespaces (#36857)

2026-08-04 08:28:43 +00:00

codex_delegate.rs

Remove obsolete ignored tests (#34558)

2026-07-21 14:57:39 +00:00

collaboration_instructions.rs

Enforce single-writer ownership for all thread histories (#36389)

2026-07-31 20:49:08 +00:00

compact_remote_parity.rs

Always assign response item IDs (#34645)

2026-07-22 01:23:44 +00:00

compact_remote.rs

Add a realtime delegation acknowledgement control (#36413)

2026-08-01 01:17:26 +00:00

compact_resume_fork.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

compact.rs

Enforce single-writer ownership for all thread histories (#36389)

2026-07-31 20:49:08 +00:00

current_time_reminder.rs

Refresh environment dates from the configured clock (#36187)

2026-07-30 16:44:18 +00:00

deprecation_notice.rs

Add indexed web search mode (#28489)

2026-06-19 05:35:57 -07:00

exec_policy.rs

Propagate approval rejection reasons (#34400)

2026-07-20 19:23:21 +00:00

exec.rs

Add network environment ID plumbing (#28766)

2026-06-18 14:09:38 +02:00

extension_sandbox.rs

Skip missing paths in filesystem sandbox entries (#34598)

2026-07-21 19:17:18 +00:00

external_auth.rs

Remove codex-core's direct reqwest dependency (#36076)

2026-07-30 04:03:33 +00:00

fork_thread.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

git_enrichment.rs

Stabilize the startup Git enrichment integration test (#36769)

2026-08-03 15:59:00 +00:00

guardian_review.rs

Add Guardian session reuse and interruption tests (#36782)

2026-08-03 19:02:26 +00:00

hooks_mcp.rs

Add per-surface MCP tool exposure controls (#36781)

2026-08-03 18:51:46 +00:00

hooks.rs

Use Git repositories as pre-tool hook test markers (#36411)

2026-08-01 01:03:42 +00:00

image_rollout.rs

Always assign response item IDs (#34645)

2026-07-22 01:23:44 +00:00

items.rs

Include item start times in completion events (#35363)

2026-07-25 16:06:54 +00:00

json_result.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

live_cli.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

mcp_auth_elicitation.rs

Add keyed shell environment policy filters (#34590)

2026-07-21 18:23:26 +00:00

mcp_auth_refresh.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

mcp_refresh_cleanup.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

mcp_startup_refresh_http_proxy.rs

Add per-surface MCP tool exposure controls (#36781)

2026-08-03 18:51:46 +00:00

mcp_tool_cache.rs

Keep MCP tool calls bound to their thread (#36355)

2026-07-31 16:12:46 +00:00

mcp_tool_exposure.rs

Raise the host-owned Codex Apps catalog limit (#36772)

2026-08-03 17:06:46 +00:00

mcp_turn_metadata.rs

Expose MCP read-only hints in tool call items (#36055)

2026-07-30 01:37:41 +00:00

mod.rs

Add acknowledged user message submission to core (#36385)

2026-07-31 20:17:25 +00:00

model_overrides.rs

[5 of 7] Replace OverrideTurnContext with ThreadSettings (#22508)

2026-05-18 21:03:51 -07:00

model_runtime_selectors.rs

Run code mode exclusively through the standalone host (#36217)

2026-07-30 20:24:29 +00:00

model_switching.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

model_visible_layout.rs

Enforce single-writer ownership for all thread histories (#36389)

2026-07-31 20:49:08 +00:00

models_cache_ttl.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

models_etag_responses.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

multi_agent_mode.rs

Enforce single-writer ownership for all thread histories (#36389)

2026-07-31 20:49:08 +00:00

multi_agent_resume.rs

Support leaf models in multi-agent v2 (#36892)

2026-08-04 12:36:14 +00:00

multi_exec_server_sandbox.rs

Test workspace write isolation across exec servers (#33861)

2026-07-17 16:07:24 +00:00

network_approval.rs

Test remote Guardian network approval scoping (#36177)

2026-07-30 15:50:04 +00:00

openai_file_mcp.rs

Resolve MCP file uploads with environment-native paths (#36002)

2026-07-29 18:06:14 +00:00

otel.rs

Propagate approval rejection reasons (#34400)

2026-07-20 19:23:21 +00:00

override_updates.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

pending_input.rs

Wake sleeping threads for queued agent mail (#34852)

2026-07-23 01:04:01 +00:00

permissions_messages.rs

Consolidate model instructions in ModelMessages (#36787)

2026-08-03 19:30:40 +00:00

personality.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

plugins.rs

Move skill catalog rendering out of core (#36364)

2026-07-31 17:12:10 +00:00

prompt_cache_key.rs

Use session IDs for prompt cache keys (#33035)

2026-07-14 10:37:23 +00:00

prompt_caching.rs

Consolidate model instructions in ModelMessages (#36787)

2026-08-03 19:30:40 +00:00

prompt_debug_tests.rs

Enable git attribution across Codex entry points (#34819)

2026-07-22 20:23:35 +00:00

quota_exceeded.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

realtime_conversation.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

realtime_initial_items.rs

Add a realtime delegation acknowledgement control (#36413)

2026-08-01 01:17:26 +00:00

remote_env.rs

Restrict shell_command to a single local environment (#36329)

2026-07-31 14:01:29 +00:00

remote_models.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

request_compression.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

request_permissions_tool.rs

Isolate apply-patch permission test variants (#36138)

2026-07-30 11:41:47 +00:00

request_permissions.rs

Propagate approval rejection reasons (#34400)

2026-07-20 19:23:21 +00:00

request_plugin_install.rs

Prepare MCP and plugin recommendations concurrently (#35675)

2026-07-27 21:43:27 +00:00

request_user_input.rs

Make user input blocking behavior explicit (#36410)

2026-08-01 00:38:10 +00:00

responses_api_proxy_headers.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

responses_lite.rs

Include code-mode tool names in Responses Lite metadata (#35271)

2026-07-25 01:05:33 +00:00

responses_system_proxy.rs

Migrate login HTTP construction to HttpClient (#34643)

2026-07-22 00:50:28 +00:00

resume_warning.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

resume.rs

Enforce single-writer ownership for all thread histories (#36389)

2026-07-31 20:49:08 +00:00

review.rs

Propagate updated permissions to review threads (#36901)

2026-08-04 14:29:24 +00:00

rmcp_client.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

rollout_budget.rs

Use provider-reported rollout budget units (#36715)

2026-08-03 09:46:38 +00:00

rollout_list_find.rs

Honor the configured SQLite home across state consumers (#34994)

2026-07-23 19:19:35 +00:00

safety_buffering.rs

[codex] Read retry model from buffering events (#31262)

2026-07-06 17:04:26 +00:00

safety_check_downgrade.rs

Update models.json (#21818)

2026-07-08 16:24:12 -07:00

search_tool.rs

Add per-surface MCP tool exposure controls (#36781)

2026-08-03 18:51:46 +00:00

shell_command.rs

Require explicit sandbox permissions with shell justifications (#36350)

2026-07-31 15:34:03 +00:00

shell_serialization.rs

test: branch on target OS instead of runner flavor (#29712)

2026-06-23 14:27:13 -07:00

shell_snapshot.rs

Wait for patch events before reading shell snapshots (#36757)

2026-08-03 14:14:41 +00:00

skill_approval.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

skills_extension.rs

Preserve discovery order for host skill path aliases (#36327)

2026-07-31 13:47:46 +00:00

skills.rs

core tests: rename automatic environment builder (#29728)

2026-06-23 21:45:06 +00:00

spawn_agent_description.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

sqlite_state.rs

Add per-surface MCP tool exposure controls (#36781)

2026-08-03 18:51:46 +00:00

stream_error_allows_next_turn.rs

Allow custom providers to opt into standalone web search (#34846)

2026-07-23 00:02:15 +00:00

stream_no_completed.rs

Allow custom providers to opt into standalone web search (#34846)

2026-07-23 00:02:15 +00:00

subagent_notifications.rs

Support leaf models in multi-agent v2 (#36892)

2026-08-04 12:36:14 +00:00

token_budget.rs

Identify agents by name in token budget context (#36815)

2026-08-04 00:51:53 +00:00

tool_harness.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

tool_parallelism.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

tools.rs

Retain attempted tool metadata across prompts (#36507)

2026-08-01 17:36:39 +00:00

truncation.rs

Add per-surface MCP tool exposure controls (#36781)

2026-08-03 18:51:46 +00:00

turn_state.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

unified_exec_process_events.rs

Enable network policy callbacks for remote exec (#35652)

2026-07-27 18:07:31 +00:00

unified_exec_zsh_fork_approvals.rs

Skip missing paths in filesystem sandbox entries (#34598)

2026-07-21 19:17:18 +00:00

unified_exec.rs

Honor per-environment login shell policy (#36811)

2026-08-03 23:33:05 +00:00

unstable_features_warning.rs

Negotiate MCP extensions per app-server session (#36910)

2026-08-04 15:23:43 +00:00

user_message_admission.rs

Add acknowledged user message submission to core (#36385)

2026-07-31 20:17:25 +00:00

user_notification.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

user_shell_cmd.rs

[codex] Warn clearly when code mode output is truncated (#28467)

2026-06-16 10:37:06 -07:00

view_image.rs

Gate plugin usage instructions by model capability (#36792)

2026-08-03 19:51:43 +00:00

web_search.rs

Update models.json (#21818)

2026-07-08 16:24:12 -07:00

websocket_fallback.rs

Pair thread environment settings (#26687)

2026-06-08 13:55:15 -07:00

window_headers.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

windows_sandbox.rs

Skip missing paths in filesystem sandbox entries (#34598)

2026-07-21 19:17:18 +00:00

workspace_roots.rs

Test workspace-root patch protection for metadata (#36171)

2026-07-30 14:34:10 +00:00