## Why
`features.multi_agent_v2.max_concurrent_threads_per_session` is meant to
be the MultiAgentV2-specific session thread cap: it counts the root
thread and all open subagent threads. The previous implementation kept
this surface tied to `agents.max_threads`, which made it a global
subagent-only cap and allowed the legacy setting to coexist with
MultiAgentV2.
## What Changed
- Added `max_concurrent_threads_per_session` to
`[features.multi_agent_v2]` with default `4`.
- Removed the `[agents] max_concurrent_threads_per_session` alias to
`agents.max_threads`.
- When MultiAgentV2 is enabled, reject `agents.max_threads` and derive
the existing internal subagent slot limit as
`max_concurrent_threads_per_session - 1`.
- Regenerated `core/config.schema.json` and added coverage for the new
config semantics.
## Result
```
➜ codex git:(jif/clean-multi-agent-v2-config) codex -c features.multi_agent_v2.enabled=true -c features.multi_agent_v2.max_concurrent_threads_per_session=3
╭────────────────────────────────────────────────────╮
│ >_ OpenAI Codex (v0.0.0) │
│ │
│ model: gpt-5.5 xhigh fast /model to change │
│ directory: ~/code/codex │
╰────────────────────────────────────────────────────╯
Tip: Update Required - This version will no longer be supported starting May 8th. Please upgrade to the latest version (https://github.com/openai/codex/releases/latest) using your preferred package manager.
› Can you try to spawn 4 agents
• I’ll try to start four lightweight agents at once and report exactly what the runtime accepts.
• Spawned Russell [no-apps] (gpt-5.5 xhigh)
└ Spawn probe 1: reply briefly that you started, then wait for further instructions. Do not do any repo work.
• Spawned Descartes [no-apps] (gpt-5.5 xhigh)
└ Spawn probe 2: reply briefly that you started, then wait for further instructions. Do not do any repo work.
• Agent spawn failed
└ Spawn probe 3: reply briefly that you started, then wait for further instructions. Do not do any repo work.
• Agent spawn failed
└ Spawn probe 4: reply briefly that you started, then wait for further instructions. Do not do any repo work.
• The runtime accepted the first two and rejected the next two with agent thread limit reached. I’m checking whether the two accepted probes have returned cleanly, then I’ll close them if needed.
```
---------
Co-authored-by: Codex <noreply@openai.com>
Addresses #17353
Problem: Codex rate-limit fetching failed when the backend returned the
new `prolite` subscription plan type.
Solution: Add `prolite` to the backend/account/auth plan mappings, keep
unknown WHAM plan values decodable, and regenerate app-server plan
schemas.
## Summary
- split `models-manager` out of `core` and add `ModelsManagerConfig`
plus `Config::to_models_manager_config()` so model metadata paths stop
depending on `core::Config`
- move login-owned/auth-owned code out of `core` into `codex-login`,
move model provider config into `codex-model-provider-info`, move API
bridge mapping into `codex-api`, move protocol-owned types/impls into
`codex-protocol`, and move response debug helpers into a dedicated
`response-debug-context` crate
- move feedback tag emission into `codex-feedback`, relocate tests to
the crates that now own the code, and keep broad temporary re-exports so
this PR avoids a giant import-only rewrite
## Major moves and decisions
- created `codex-models-manager` as the owner for model
cache/catalog/config/model info logic, including the new
`ModelsManagerConfig` struct
- created `codex-model-provider-info` as the owner for provider config
parsing/defaults and kept temporary `codex-login`/`codex-core`
re-exports for old import paths
- moved `api_bridge` error mapping + `CoreAuthProvider` into
`codex-api`, while `codex-login::api_bridge` temporarily re-exports
those symbols and keeps the `auth_provider_from_auth` wrapper
- moved `auth_env_telemetry` and `provider_auth` ownership to
`codex-login`
- moved `CodexErr` ownership to `codex-protocol::error`, plus
`StreamOutput`, `bytes_to_string_smart`, and network policy helpers to
protocol-owned modules
- created `codex-response-debug-context` for
`extract_response_debug_context`, `telemetry_transport_error_message`,
and related response-debug plumbing instead of leaving that behavior in
`core`
- moved `FeedbackRequestTags`, `emit_feedback_request_tags`, and
`emit_feedback_request_tags_with_auth_env` to `codex-feedback`
- deferred removal of temporary re-exports and the mechanical import
rewrites to a stacked follow-up PR so this PR stays reviewable
## Test moves
- moved auth refresh coverage from `core/tests/suite/auth_refresh.rs` to
`login/tests/suite/auth_refresh.rs`
- moved text encoding coverage from
`core/tests/suite/text_encoding_fix.rs` to
`protocol/src/exec_output_tests.rs`
- moved model info override coverage from
`core/tests/suite/model_info_overrides.rs` to
`models-manager/src/model_info_overrides_tests.rs`
---------
Co-authored-by: Codex <noreply@openai.com>
