Stacked on #27365.
## Stack note
[#27365](https://github.com/openai/codex/pull/27365) kept `thread/start`
unchanged and converted its input in `thread_processor`. This PR updates
`thread/start` to accept explicit functions and namespaces directly.
Legacy per-tool arrays are still accepted and converted while reading
the request. As a result, `thread_processor` can validate and pass the
tools through directly, which is why some code added in #27365 is
removed here.
## Why
`thread/start.dynamicTools` still repeats namespace data on each
function even though core now stores explicit namespace groups. The
request API should use the same shape so each namespace has one
description and one member list.
## What changed
- Accept top-level functions and explicit namespace objects in
`dynamicTools`.
- Continue accepting fully legacy flat arrays, including
`exposeToContext`.
- Reject arrays that mix legacy and canonical entries.
- Reuse the protocol types directly and remove the temporary app-server
adapter.
- Update validation, docs, the test client, and generated schemas.
## Test plan
- `just test -p codex-app-server-protocol`
- `just test -p codex-app-server
dynamic_tool_call_round_trip_sends_text_content_items_to_model`
- `just test -p codex-app-server
thread_start_normalizes_legacy_dynamic_tools_into_model_request`
- `just test -p codex-app-server
thread_start_rejects_mixed_dynamic_tool_formats`
- `just test -p codex-app-server
thread_start_rejects_hidden_dynamic_tools_without_namespace`
Follow-up to #27356.
## Stack note
This PR changes Codex's internal dynamic-tool shape while leaving
`thread/start` unchanged. App-server therefore converts the existing
per-tool input into explicit functions and namespaces before passing it
to core.
[#27371](https://github.com/openai/codex/pull/27371) updates
`thread/start` to use the same explicit shape and removes this temporary
conversion.
## Why
Dynamic tools repeat namespace metadata on every function. Core should
keep one explicit namespace with its member tools so descriptions and
membership stay consistent across sessions and runtime planning.
## What changed
- Represent dynamic tools as top-level functions or explicit namespaces
in protocol and session state.
- Read old flat rollout metadata and write the canonical hierarchy.
- Flatten namespace members only when registering callable tools.
- Keep `thread/start.dynamicTools` flat for now and normalize it at the
app-server boundary.
New builds can read old rollout metadata. Older builds cannot read newly
written hierarchical metadata.
## Test plan
- `just test -p codex-app-server
thread_start_normalizes_legacy_dynamic_tools_into_model_request`
- `just test -p codex-protocol
session_meta_normalizes_legacy_dynamic_tools`
- `just test -p codex-core
resume_restores_dynamic_tools_from_rollout_with_sqlite_enabled`
- `just test -p codex-core
tool_search_returns_deferred_dynamic_tool_and_routes_follow_up_call`
- `just test -p codex-core code_mode_can_call_hidden_dynamic_tools`
- `just test -p codex-tools`
## Why
Tool families already disagree on what their existing `duration` fields
mean, so lifecycle latency should live on the shared item envelope
instead of being inferred from per-tool execution fields. Carrying that
envelope through app-server notifications gives downstream consumers one
reusable timing signal without pretending every tool has the same
execution semantics.
## What changed
- Adds `started_at_ms` to core `ItemStartedEvent` values and
`completed_at_ms` to core `ItemCompletedEvent` values.
- Populates those timestamps in the shared session lifecycle emitters,
so protocol-native items get timing without each producer tracking its
own clock state.
- Exposes `startedAtMs` on app-server `item/started` notifications and
`completedAtMs` on `item/completed` notifications.
- Maps the lifecycle timestamps through the app-server boundary while
leaving legacy-converted notifications nullable when no lifecycle
timestamp exists.
- Regenerates the app-server JSON schema and TypeScript fixtures for the
notification-envelope change and updates downstream fixtures that
construct those notifications directly.
- Extends the existing web-search and image-generation integration flows
to assert the new lifecycle timestamps on the native item events.
## Verification
- `cargo check -p codex-protocol -p codex-core -p
codex-app-server-protocol -p codex-app-server -p codex-tui -p codex-exec
-p codex-app-server-client`
- `cargo test -p codex-core --test all web_search_item_is_emitted`
- `cargo test -p codex-core --test all
image_generation_call_event_is_emitted`
- `cargo test -p codex-app-server-protocol`
---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/20514).
* #18748
* #18747
* #17090
* #17089
* __->__ #20514
Deferred dynamic tools need to round-trip a namespace so a tool returned
by `tool_search` can be called through the same registry key that core
uses for dispatch.
This change adds namespace support for dynamic tool specs/calls,
persists it through app-server thread state, and routes dynamic tool
calls by full `ToolName` while still sending the app the leaf tool name.
Deferred dynamic tools must provide a namespace; non-deferred dynamic
tools may remain top-level.
It also introduces `LoadableToolSpec` as the shared
function-or-namespace Responses shape used by both `tool_search` output
and dynamic tool registration, so dynamic tools use the same wrapping
logic in both paths.
Validation:
- `cargo test -p codex-tools`
- `cargo test -p codex-core tool_search`
---------
Co-authored-by: Sayan Sisodiya <sayan@openai.com>
This extends dynamic_tool_calls to allow us to hide a tool from the
model context but still use it as part of the general tool calling
runtime (for ex from js_repl/code_mode)
Took over the work that @aaronl-openai started here:
https://github.com/openai/codex/pull/10397
Now that app-server clients are able to set up custom tools (called
`dynamic_tools` in app-server), we should expose a way for clients to
pass in not just text, but also image outputs. This is something the
Responses API already supports for function call outputs, where you can
pass in either a string or an array of content outputs (text, image,
file):
https://platform.openai.com/docs/api-reference/responses/create#responses_create-input-input_item_list-item-function_tool_call_output-output-array-input_image
So let's just plumb it through in Codex (with the caveat that we only
support text and image for now). This is implemented end-to-end across
app-server v2 protocol types and core tool handling.
## Breaking API change
NOTE: This introduces a breaking change with dynamic tools, but I think
it's ok since this concept was only recently introduced
(https://github.com/openai/codex/pull/9539) and it's better to get the
API contract correct. I don't think there are any real consumers of this
yet (not even the Codex App).
Old shape:
`{ "output": "dynamic-ok", "success": true }`
New shape:
```
{
"contentItems": [
{ "type": "inputText", "text": "dynamic-ok" },
{ "type": "inputImage", "imageUrl": "data:image/png;base64,AAA" }
]
"success": true
}
```
## Summary
Add dynamic tool injection to thread startup in API v2, wire dynamic
tool calls through the app server to clients, and plumb responses back
into the model tool pipeline.
### Flow (high level)
- Thread start injects `dynamic_tools` into the model tool list for that
thread (validation is done here).
- When the model emits a tool call for one of those names, core raises a
`DynamicToolCallRequest` event.
- The app server forwards it to the client as `item/tool/call`, waits
for the client’s response, then submits a `DynamicToolResponse` back to
core.
- Core turns that into a `function_call_output` in the next model
request so the model can continue.
### What changed
- Added dynamic tool specs to v2 thread start params and protocol types;
introduced `item/tool/call` (request/response) for dynamic tool
execution.
- Core now registers dynamic tool specs at request time and routes those
calls via a new dynamic tool handler.
- App server validates tool names/schemas, forwards dynamic tool call
requests to clients, and publishes tool outputs back into the session.
- Integration tests
sayan-oai ·
rhan-oai ·
pash-openai ·
Channing Conger ·
Owen Lin ·
jif-oai ·