## Summary `cargo test` has entails both running standard Rust tests and doctests. It turns out that the doctest discovery is fairly slow, and it's a cost you pay even for crates that don't include any doctests. This PR disables doctests with `doctest = false` for crates that lack any doctests. For the collection of crates below, this speeds up test execution by >4x. E.g., before this PR: ``` Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml Time (mean ± σ): 1.849 s ± 4.455 s [User: 0.752 s, System: 1.367 s] Range (min … max): 0.418 s … 14.529 s 10 runs ``` And after: ``` Benchmark 1: cargo test -p codex-utils-absolute-path -p codex-utils-cache -p codex-utils-cli -p codex-utils-home-dir -p codex-utils-output-truncation -p codex-utils-path -p codex-utils-string -p codex-utils-template -p codex-utils-elapsed -p codex-utils-json-to-toml Time (mean ± σ): 428.6 ms ± 6.9 ms [User: 187.7 ms, System: 219.7 ms] Range (min … max): 418.0 ms … 436.8 ms 10 runs ``` For a single crate, with >2x speedup, before: ``` Benchmark 1: cargo test -p codex-utils-string Time (mean ± σ): 491.1 ms ± 9.0 ms [User: 229.8 ms, System: 234.9 ms] Range (min … max): 480.9 ms … 512.0 ms 10 runs ``` And after: ``` Benchmark 1: cargo test -p codex-utils-string Time (mean ± σ): 213.9 ms ± 4.3 ms [User: 112.8 ms, System: 84.0 ms] Range (min … max): 206.8 ms … 221.0 ms 13 runs ``` Co-authored-by: Codex <noreply@openai.com>
codex-tools
codex-tools is intended to become the home for tool-related code that is
shared across multiple crates and does not need to stay coupled to
codex-core.
Today this crate is intentionally small. It currently owns the shared tool
schema and Responses API tool primitives that no longer need to live in
core/src/tools/spec.rs or core/src/client_common.rs:
JsonSchemaAdditionalPropertiesToolDefinitionToolSpecConfiguredToolSpecResponsesApiToolFreeformToolFreeformToolFormatLoadableToolSpecResponsesApiWebSearchFiltersResponsesApiWebSearchUserLocationResponsesApiNamespaceResponsesApiNamespaceTool- code-mode
ToolSpecadapters andexec/waitspec builders - MCP resource and
test_sync_toolspec builders - local host tool spec builders for shell/exec/request-permissions/view-image
- collaboration and agent-job
ToolSpecbuilders for spawn/send/wait/close,request_user_input, and CSV fanout/reporting - discoverable-tool models, client filtering, and
ToolSpecbuilders fortool_searchandrequest_plugin_install parse_tool_input_schema()parse_dynamic_tool()parse_mcp_tool()create_tools_json_for_responses_api()mcp_call_tool_result_output_schema()tool_definition_to_responses_api_tool()dynamic_tool_to_loadable_tool_spec()dynamic_tool_to_responses_api_tool()mcp_tool_to_responses_api_tool()mcp_tool_to_deferred_responses_api_tool()augment_tool_spec_for_code_mode()tool_spec_to_code_mode_tool_definition()
That extraction is the first step in a longer migration. The goal is not to
move all of core/src/tools into this crate in one shot. Instead, the plan is
to peel off reusable pieces in reviewable increments while keeping
compatibility-sensitive orchestration in codex-core until the surrounding
boundaries are ready.
Vision
Over time, this crate should hold tool-facing primitives that are shared by multiple consumers, for example:
- schema and spec data models
- tool input/output parsing helpers
- tool metadata and compatibility shims that do not depend on
codex-core - other narrowly scoped utility code that multiple crates need
The corresponding non-goals are just as important:
- do not move
codex-coreorchestration here prematurely - do not pull
Session/TurnContext/ approval flow / runtime execution logic into this crate unless those dependencies have first been split into stable shared interfaces - do not turn this crate into a grab-bag for unrelated helper code
Migration approach
The expected migration shape is:
- Move low-coupling tool primitives here.
- Switch non-core consumers to depend on
codex-toolsdirectly. - Leave compatibility-sensitive adapters in
codex-corewhile downstream call sites are updated. - Only extract higher-level tool infrastructure after the crate boundaries are clear and independently testable.
That means it is normal for codex-core to temporarily re-export types or
helpers from codex-tools during the transition.
Crate conventions
This crate should start with stricter structure than core/src/tools so it
stays easy to grow:
src/lib.rsshould remain exports-only.- Business logic should live in named module files such as
foo.rs. - Unit tests for
foo.rsshould live in a siblingfoo_tests.rs. - The implementation file should wire tests with:
#[cfg(test)]
#[path = "foo_tests.rs"]
mod tests;
If this crate starts accumulating code that needs runtime state from
codex-core, that is a sign to revisit the extraction boundary before adding
more here.