## Summary
- update the self-serve business usage-based limit message to direct
users to their admin for additional credits
- add a focused unit test for the self_serve_business_usage_based plan
branch
Added also:
If you are at a rate limit but you still have credits, codex cli would
tell you to switch the model. We shouldnt do this if you have credits so
fixed this.
## Test
- launched the source-built CLI and verified the updated message is
shown for the self-serve business usage-based plan

Send input now sends messages as assistant message and with this format:
```
author: /root/worker_a
recipient: /root/worker_a/tester
other_recipients: []
Content: bla bla bla. Actual content. Only text for now
```
This PR add an URI-based system to reference agents within a tree. This
comes from a sync between research and engineering.
The main agent (the one manually spawned by a user) is always called
`/root`. Any sub-agent spawned by it will be `/root/agent_1` for example
where `agent_1` is chosen by the model.
Any agent can contact any agents using the path.
Paths can be used either in absolute or relative to the calling agents
Resume is not supported for now on this new path
- Split the feature system into a new `codex-features` crate.
- Cut `codex-core` and workspace consumers over to the new config and
warning APIs.
Co-authored-by: Ahmed Ibrahim <219906144+aibrahim-oai@users.noreply.github.com>
Co-authored-by: Codex <noreply@openai.com>
Add a representation of the agent graph. This is now used for:
* Cascade close agents (when I close a parent, it close the kids)
* Cascade resume (oposite)
Later, this will also be used for post-compaction stuffing of the
context
Direct fix for: https://github.com/openai/codex/issues/14458
Make `interrupted` an agent state and make it not final. As a result, a
`wait` won't return on an interrupted agent and no notification will be
send to the parent agent.
The rationals are:
* If a user interrupt a sub-agent for any reason, you don't want the
parent agent to instantaneously ask the sub-agent to restart
* If a parent agent interrupt a sub-agent, no need to add a noisy
notification in the parent agen
## Why
PR #13783 moved the `codex.rs` unit tests into `codex_tests.rs`. This
applies the same extraction pattern across the rest of `codex-rs/core`
so the production modules stay focused on runtime code instead of large
inline test blocks.
Keeping the tests in sibling files also makes follow-up edits easier to
review because product changes no longer have to share a file with
hundreds or thousands of lines of test scaffolding.
## What changed
- replaced each inline `mod tests { ... }` in `codex-rs/core/src/**`
with a path-based module declaration
- moved each extracted unit test module into a sibling `*_tests.rs`
file, using `mod_tests.rs` for `mod.rs` modules
- preserved the existing `cfg(...)` guards and module-local structure so
the refactor remains structural rather than behavioral
## Testing
- `cargo test -p codex-core --lib` (`1653 passed; 0 failed; 5 ignored`)
- `just fix -p codex-core`
- `cargo fmt --check`
- `cargo shear`