## What changed
- Add the default-disabled `code_mode_tool_search` feature to expose `await tools.tool_search({query: "...", limit: 8})` in code mode when the model supports tool search.
- Return BM25-ranked deferred tools as `{tools: [{name, description}]}`, including callable names and TypeScript declarations for use in later code cells.
- Filter results through the current step's nested-tool policy before applying the limit, preserving namespace restrictions, normalized identities, description prefixes, and schema budgets.
- Add ranked-search guidance while retaining `ALL_TOOLS` catalog discovery and description overrides.
## Testing
Add coverage for feature and model-capability gating, namespace restrictions, argument validation, schema budgets, and discovery followed by deferred MCP and dynamic tool calls. Extend the scenario snapshot to cover search, invocation, yielding, and completion through `wait`.
GitOrigin-RevId: 092a29dd5f0773c518f53a001b9cafb917422f13
## Why
Tool availability can change between calls. Conditioning discovery guidance on whether deferred tools are currently present changes the `exec` description when the catalog changes.
## What changed
Always include the configured discovery guidance in the Code Mode `exec` description, even when no deferred tools are present. The default guidance explains how to find tools in `ALL_TOOLS` and notes that availability can change between calls. Custom guidance and explicit empty overrides remain supported.
## Testing
Add regression coverage for stable guidance with empty and populated deferred tool catalogs in both Code Mode configurations, including custom and empty overrides. Update tool-description assertions and request snapshots.
GitOrigin-RevId: 086ea19a48e3c51ec8c429a619676a936d658721
## Why
Changing a deferred tool's output schema could add or remove the shared MCP type preamble from the `exec` description.
## What changed
Include the default or configured MCP TypeScript preamble whenever `code_mode_only` is enabled, regardless of the available tools' output schemas. Preserve an empty preamble override as a way to omit the section.
## Testing
Add a regression test that checks description stability when a deferred tool gains an MCP output schema, covering default, custom, and empty preambles. Update description expectations, request snapshots, and two Guardian context-budget test thresholds for the added preamble.
GitOrigin-RevId: 725035d6159e9da3c4beff5482c426c082e768b4
## Why
Fixed schema budgets can strip parameter descriptions from large MCP tools or render their Code Mode input types as `unknown`. Allow larger budgets to preserve that guidance.
## What changed
- Add `mcp_servers.<name>.tool_input_schema_max_bytes` to configure the UTF-8 byte threshold for best-effort input schema compaction, retaining the 5,000-byte default.
- Add `features.code_mode.tool_input_schema_max_bytes` for rendered input types. Use the largest of the 16,000-byte default, the Code Mode setting, and the ordinary MCP server's explicit setting.
- Apply rendering budgets to prompt declarations and the runtime tool catalog, and avoid reusing cached declarations after the Code Mode budget changes.
## Testing
Add coverage for UTF-8 compaction thresholds, budget precedence, configuration round trips, and preservation of parameter guidance in both the Code Mode prompt and `ALL_TOOLS`.
GitOrigin-RevId: 0ef2823a614d4794e636f518b09c0b03a5239b45
## What changed
- Add `tools.code_mode` catalog messages for `exec`, `wait`, deferred-tool guidance, and shared MCP TypeScript definitions.
- Render `{{ default_exec_yield_time_ms }}` and `{{ image_helper }}` in `exec` descriptions while preserving runtime tool declarations and the freeform grammar.
- Resolve `wait` descriptions and parameter schemas independently, falling back to bundled parameters for invalid or unsupported schemas.
- Use the active model's Code Mode messages, including after mid-turn model changes. Missing overrides retain bundled defaults; empty text overrides suppress the corresponding text.
## Testing
Add coverage for literal template substitution, runtime section preservation, independent `wait` overrides and fallback behavior, mid-turn model changes, and a yielded cell completing through `wait` with catalog messages.
GitOrigin-RevId: e542a0cd47a7138a414871192cee47790ed1214e
## Why
Code Mode rendered document-local `$ref` values as `unknown`, hiding referenced
input and structured-output shapes from generated TypeScript declarations.
## What changed
- Resolve fragment-only JSON Pointer references against the root schema,
including escaped and percent-encoded pointer segments.
- Preserve `$ref` siblings as intersections and parenthesize unions used in
`allOf` intersections.
- Bound recursive and repeated expansion, intermediate rendering work, and
final output size, falling back to `unknown` when a limit is reached or a
reference cannot be resolved safely.
## Testing
Add unit coverage for recursive, escaped, nested-resource, dangling, and
oversized references, plus integration coverage for generated Code Mode tool
descriptions and MCP structured output types.
GitOrigin-RevId: 95c6aa32e25325b5be9359dfac3b3328e5e7a499
## What changed
- Add the gated `unified_image_budget` feature for models that support original image detail or Responses Lite.
- Apply one 6,000-pixel, 10,000-patch preprocessing limit regardless of legacy image detail hints.
- Hide detail controls from `view_image` and code mode while continuing to accept existing hints for compatibility.
- Preserve detail-based resizing and tool contracts for unsupported models.
## Testing
- Cover unified resizing limits, Responses Lite, legacy detail hints, unsupported models, and `view_image` integration in code mode.
GitOrigin-RevId: cb07bff1669a96599fdfd076b3d9ec80f2b6fff7
## What changed
- Add the experimental `code_mode_buffered_exec` feature.
- When enabled, default code-mode `exec` calls without an explicit
`yield_time_ms` to 30 seconds instead of 10 seconds.
- Report the effective default in the model-visible `exec` tool description.
## Testing
- Verify that the generated tool description advertises the 30-second default
when the feature is enabled.
GitOrigin-RevId: 0eea4d0105137f09050ce31aad18c25c79df6b2a
## Why
When MCP tools are deferred behind `tool_search`, Code mode keeps them
callable but omits their individual declarations from the initial `exec`
description. The shared MCP `CallToolResult` types were derived only
from directly rendered tools, so deferring every MCP tool also removed
the common response contract that models need to interpret MCP results.
This restores that contract without undoing the context savings from
deferred tool definitions. This is a follow-up to #29486.
## What changed
- Track deferred Code-mode tool definitions separately from directly
rendered definitions.
- Render the shared MCP type preamble when either direct or deferred MCP
tools are available.
- Keep deferred tool declarations out of the initial prompt.
- Add unit and integration coverage for deferred MCP tools.
## Testing
- `just test -p codex-code-mode-protocol`
- `just test -p codex-core
code_mode_only_guides_all_tools_search_and_calls_deferred_app_tools`
## Summary
- reject HTTP(S) image URLs from the shared code-mode output-image
normalization path
- return a concise model-visible tool error so the model can recover on
its next turn
- apply the targeted rejection to both `image()` and `generatedImage()`
- leave other non-empty image URL values to existing downstream handling
The returned error is:
> Tool call failed: remote image URLs are not supported in tool outputs.
Pass a base64 data URI instead
## Why
Responses Lite cannot lower a remote image URL emitted from a structured
tool output. Rejecting HTTP(S) values in the Codex harness preserves the
tool-call metadata and gives the model a recoverable next turn instead
of invalidating the sample.
## Test coverage
The regression is covered primarily by a `test_codex()` agent
integration test that simulates the Responses API exchange and asserts
the failed model-visible exec output. A supplemental runtime test covers
both `http://` and `https://` inputs across both image output helpers.
## Test plan
- `cd codex-rs && just test -p codex-code-mode`
- `cd codex-rs && just test -p codex-code-mode-protocol`
- `cd codex-rs && just test -p codex-core
code_mode_image_helper_rejects_remote_url`
- `cd codex-rs && just fmt`
- `git diff --check origin/main...HEAD`
Related context: https://github.com/openai/openai/pull/1022346
This is phase 1 of a 4 phase stack:
1. **Add protocol and host crates for new IPC code mode implementation**
2. Create the new standalone binary
3. Create a new IPC `CodeModeSessionProvider` to use new binary
4. Remove v8 from core and only use IPC provider
## Add protocol and host crates for new IPC code mode implementation
Establish a clean process boundary without changing the existing
in-process behavior.
- Add the codex-code-mode-protocol crate for shared session, runtime,
response, and tool-definition types.
- Move protocol-facing code out of the V8-backed implementation.
- Add a buildable codex-code-mode-host crate as the foundation for the
standalone process.
- Keep the existing in-process runtime as the active implementation.
Alex Zamoshchin