## Summary
This PR fully reverts the previously merged Agent Identity runtime
integration from the old stack:
https://github.com/openai/codex/pull/17387/changes
It removes the Codex-side task lifecycle wiring, rollout/session
persistence, feature flag plumbing, lazy `auth.json` mutation,
background task auth paths, and request callsite changes introduced by
that stack.
This leaves the repo in a clean pre-AgentIdentity integration state so
the follow-up PRs can reintroduce the pieces in smaller reviewable
layers.
## Stack
1. This PR: full revert
2. https://github.com/openai/codex/pull/18871: move Agent Identity
business logic into a crate
3. https://github.com/openai/codex/pull/18785: add explicit
AgentIdentity auth mode and startup task allocation
4. https://github.com/openai/codex/pull/18811: migrate auth callsites
through AuthProvider
## Testing
Tests: targeted Rust checks, cargo-shear, Bazel lock check, and CI.
## Summary
Introduces a single background/control-plane agent task for ChatGPT
backend requests that do not have a thread-scoped task, with
`AuthManager` owning the default ChatGPT backend authorization decision.
Callers now ask `AuthManager` for the default ChatGPT backend
authorization header. `AuthManager` decides whether that is bearer or
background AgentAssertion based on config/internal state, while
low-level bootstrap paths can explicitly request bearer-only auth.
This PR is stacked on PR4 and focuses on the shared background task auth
plumbing plus the first tranche of backend/control-plane consumers. The
remaining callsite wiring is split into PR4.2 to keep review size down.
## Stack
- PR1: https://github.com/openai/codex/pull/17385 - add
`features.use_agent_identity`
- PR2: https://github.com/openai/codex/pull/17386 - register agent
identities when enabled
- PR3: https://github.com/openai/codex/pull/17387 - register agent tasks
when enabled
- PR3.1: https://github.com/openai/codex/pull/17978 - persist and
prewarm registered tasks per thread
- PR4: https://github.com/openai/codex/pull/17980 - use task-scoped
`AgentAssertion` for downstream calls
- PR4.1: this PR - introduce AuthManager-owned background/control-plane
`AgentAssertion` auth
- PR4.2: https://github.com/openai/codex/pull/18260 - use background
task auth for additional backend/control-plane calls
## What Changed
- add background task registration and assertion minting inside
`codex-login`
- persist `agent_identity.background_task_id` separately from
per-session task state
- make `BackgroundAgentTaskManager` private to `codex-login`; call sites
do not instantiate or pass it around
- teach `AuthManager` the ChatGPT backend base URL and feature-derived
background auth mode from resolved config
- expose bearer-only helpers for bootstrap/registration/refresh-style
paths that must not use AgentAssertion
- wire `AuthManager` default ChatGPT authorization through app listing,
connector directory listing, remote plugins, MCP status/listing,
analytics, and core-skills remote calls
- preserve bearer fallback when the feature is disabled, the backend
host is unsupported, or background task registration is not available
## Validation
- `just fmt`
- `cargo check -p codex-core -p codex-login -p codex-analytics -p
codex-app-server -p codex-cloud-requirements -p codex-cloud-tasks -p
codex-models-manager -p codex-chatgpt -p codex-model-provider -p
codex-mcp -p codex-core-skills`
- `cargo test -p codex-login agent_identity`
- `cargo test -p codex-model-provider bearer_auth_provider`
- `cargo test -p codex-core agent_assertion`
- `cargo test -p codex-app-server remote_control`
- `cargo test -p codex-cloud-requirements fetch_cloud_requirements`
- `cargo test -p codex-models-manager manager::tests`
- `cargo test -p codex-chatgpt`
- `cargo test -p codex-cloud-tasks`
- `just fix -p codex-core -p codex-login -p codex-analytics -p
codex-app-server -p codex-cloud-requirements -p codex-cloud-tasks -p
codex-models-manager -p codex-chatgpt -p codex-model-provider -p
codex-mcp -p codex-core-skills`
- `just fix -p codex-app-server`
- `git diff --check`
## Summary
- move skill loading and management into codex-core-skills
- leave codex-core with the thin integration layer and shared wiring
## Testing
- CI
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Co-authored-by: Codex <noreply@openai.com>