Module bootstrap 

CLI bootstrap: argv → resolved mode + runtime handle, or short-circuit exit.

Ports the ordered pipeline of .references/pi/packages/coding-agent/src/ main.ts into a testable orchestrator. Everything that touches the process (env vars, TTY status, stdin, stdout/stderr) flows through an injected BootstrapIo trait; everything that builds the agent-session runtime flows through an injected RuntimeFactory trait. Pure helpers (resolve_app_mode, validators) are public so the integrator and tests can drive them directly.

Pipeline order (matches main.ts:472-858)

1. Reset timings (no-op here; the timings module is a sibling concern).
2. Offline mode: args.contains("--offline") || PI_OFFLINE → set PI_OFFLINE=1, PI_SKIP_VERSION_CHECK=1.
3. Package/config short-circuit (pi install …, pi config …).
4. parse_args + report diagnostics (errors exit 1, warnings continue).
5. --version → print version, exit 0.
6. --export → export session file, exit 0/1.
7. resolve_app_mode + take_over_stdout (unless interactive or plain runtime metadata command).
8. RPC + @file guard.
9. Fork / session-id flag validation.
10. run_migrations (records migrated_providers + deprecation_warnings).
11. Startup settings + first-time setup (interactive only — gated, the UI surface itself is a sibling slice).
12. Session-dir resolution + create_session_manager.
13. --name append + validation.
14. Trust store + resource paths.
15. Build runtime via factory.
16. --help (with extension flags) → exit 0.
17. --list-models → exit 0.
18. Read piped stdin (skip RPC); demote interactive→print when stdin present.
19. Prepare initial message.
20. Report runtime diagnostics (errors exit 1, with extension hint when relevant).
21. Non-interactive requires session.model, else no-models message + exit 1.
22. PI_STARTUP_BENCHMARK guard.
23. Return BootstrapOutcome::Dispatch with the resolved mode + handle.

Structs

BootstrapInputs

Inputs to run_bootstrap.

Dispatched

A bootstrap that reached the dispatch stage.

FlagValidationError

Error returned by validate_fork_flags / validate_session_id_flags.

RuntimeFactoryOptions

Inputs to RuntimeFactory::create.

RuntimeHandle

Result of a successful runtime construction.

Enums

AppMode

Resolved application mode.

BootstrapOutcome

Result of running the bootstrap pipeline.

Traits

BootstrapIo

Process-level I/O surface the bootstrap needs.

RuntimeFactory

Injected factory that turns a session manager + CLI args into a live AgentSessionRuntime.

Functions

is_plain_runtime_metadata_command

Whether --help/--list-models should run without taking over stdout.

is_truthy_env_flag

Truthy env-flag test matching isTruthyEnvFlag (main.ts:94-97).

resolve_app_mode

Resolve the application mode from parsed args and TTY status.

run_bootstrap

Run the bootstrap pipeline.

validate_fork_flags

--fork cannot combine with --session/--continue/--resume/--no-session.

validate_name

Validate --name/-n post-parse.

validate_session_id_flags

--session-id cannot combine with --session/--continue/--resume.