## Thinking Path > - Paperclip is the open source app people use to manage AI agents for work. > - When someone messages an agent, the turn must start fast. Time to first token (TTFT) is a first-class metric. > - The Phase 0 baseline (#19846) found that every local turn launches a new runner and loads the provider session again, because `per_turn` is the default lifecycle. That made a follow-up message slower than a new task. > - Warm runners keep the runner and provider session alive between runs. #19874 fixed the defect that broke warm OpenCode follow-ups, and #19879 bounds an idle warm runner whose controller dies. > - This pull request makes warm the default for local Codex and OpenCode agents, and migrates existing agents that only carried the old creation default. > - The benefit: follow-up TTFT p50 drops from 12.0 s to 4.7 s (Codex) and from 21.7 s to 4.2 s (OpenCode), with no new restart-chaos failures. ## Linked Issues or Issue Description Refs #19846 (TTFT baseline), #19852 (startup sub-spans), #19874 (warm completion contract), #19879 (warm reconnect grace). **What existing behavior does this improve?** The default runner lifecycle for native agents, and how a follow-up message starts. **Current behavior** Agent creation writes `lifecycleMode: "per_turn"` into every native agent. Every follow-up launches a new runner and restores the provider session: 4.2 s (Codex) and 16.3 s (OpenCode) at p50 before the turn starts. **Proposed behavior** New native agents store no lifecycle. On a local target, an unset lifecycle resolves to `warm` with the default 5-minute idle window for Codex and OpenCode. Other harnesses, remote targets and managed providers without warm support stay `per_turn`. An explicit choice always wins. Migration 0443 clears the stored creation default from existing agents, except where an edit set "Turn by turn" explicitly. **Reason and benefit** Measured locally (`doc/plans/2026-11-07-warm-follow-up-ttft.md`). Warm follow-ups are 2.6–5× faster for Codex and OpenCode, and restart recovery latency is equal or lower. ## What Changed - `native-lifecycle.ts`: an unset `agentMode` resolves to warm (5-minute idle window) for local `codex_app_server` and `opencode_server` agents. `runtime-selection.ts` passes `localTarget`. Explicit `per_turn` or `warm` wins. An admitted session keeps its persisted policy. ACPX Claude stays `per_turn`: it relaunches its provider process on every follow-up by design, so warm did not shorten its follow-up (10.7 s warm vs 10.5 s per_turn). - Creation and configuration writes no longer store `lifecycleMode: "per_turn"` for Codex, Claude or OpenCode. This covers `normalizePaperclipRunnerAdapterConfig` (runs on every create and update), `paperclipRunnerTransitionConfig` (switching to the native runner), `agent-runner-selection.ts`, `codex-local` `build-config.ts`, and the simplified new-agent setup (`paperclipRunnerCreationLifecycle` in `@paperclipai/shared`). Grok, Pi and Cursor keep their explicit value. - Agent form: the Runner lifecycle field shows the unset state as "Automatic". "Turn by turn" and "Warm session" remain. - Migration `0443_native_warm_follow_up_default.sql`: clears `lifecycleMode = 'per_turn'` from native Codex, OpenCode and Claude agents unless `agent_config_revisions` shows an edit that set it to `per_turn`. Each migrated agent gets an `agent.updated` activity entry with the old value (`actor_id = migration:native-warm-follow-up-default`). Creation records no revision, so a "Turn by turn" pick made at creation cannot be told apart from the old default. The product owner approved migrating those agents. Claude agents follow the default, which is `per_turn` today. - Restart chaos harness and TTFT driver: `--lifecycle per_turn|warm|default` (saved in the wave plan). `default` removes the catalog's pinned lifecycle, so a wave exercises the real default path. - Docs: `doc/DEVELOPING.md` "Runner lifecycle default", and the results in `doc/plans/2026-11-07-warm-follow-up-ttft.md`, which also documents baseline finding 4 (Claude's resumed turn-start gap is ACPX's per-turn process generation, not the provider). ## Verification - `server`: `native-lifecycle.test.ts` (new default cases: local Codex and OpenCode warm, Claude, remote, unknown target, unmeasured harness, managed Claude, admitted per-turn session, explicit choices, non-native adapter), `agent-runner-selection.test.ts`, `runtime-selection.test.ts` (335 pass). - `packages/db`: `native-warm-follow-up-default-migration.test.ts` on embedded Postgres. Default agents are cleared, the explicit edit is kept, other harnesses and legacy adapters are untouched, audit rows are written once, and a rerun is a no-op. Without the explicit-edit filter the test fails. `check:migrations` passes. - `codex-local` `build-config.test.ts` (65), `ui` `config-fields.test.tsx` (40), restart-chaos unit tests (134), `tsc --noEmit` for `server`. - `adapter-utils` `paperclip-runner-lifecycle-default.test.ts`: configuration writes and adapter conversion store no lifecycle for Codex, OpenCode and Claude, keep `per_turn` for the others, and preserve explicit choices. It fails without the fix. - End-to-end default check on this branch (`ttft-baseline.ts --lifecycle default`, codex and opencode, 2 samples): the agents read back with no stored lifecycle, and every follow-up reused the runner and provider session (no `runner.process.launch`). Follow-up TTFT was 3.6–4.8 s. This check found the per-write `per_turn` injection fixed here. - Restart chaos (codex and opencode, A1/B1/B5, K1/K2/K6, seed 4242), 8/8 PASS each with no open signatures: forced warm, forced per_turn, and `--lifecycle default` on this branch (agents created without a lifecycle). - `pnpm verify` selects broader CI (harness config is a global input), so required CI supplies the broad coverage. ## Risks - Behavior change: local Codex and OpenCode agents keep a runner and provider process for up to 5 minutes after a run. Instance sleep waits for that idle window. The process is reaped by the idle timer, by graceful shutdown, or by the #19879 reconnect grace if its controller dies. - Migration: agents whose "Turn by turn" was chosen at creation become Automatic. The activity entry records the old value; choosing "Turn by turn" restores it. - Previous-release story (`rules/upgrade-safe-run-state.mdc`): a task session keeps the lifecycle policy it was admitted with, so sessions saved before this change stay `per_turn`. New sessions get the default. No run, checkpoint or launch state changes shape. > For core feature work, check [`ROADMAP.md`](ROADMAP.md) first and discuss it in `#dev` before opening the PR. Feature PRs that overlap with planned core work may need to be redirected — check the roadmap first. See `CONTRIBUTING.md`. ## Model Used - Anthropic Claude Opus 5.5 (`claude-opus-5-5`) in Claude Code, with tool use (shell, file edit, test execution). ## Checklist - [x] I have included a thinking path that traces from project context to this change - [x] I have specified the model used (with version and capability details) - [x] I have checked ROADMAP.md and confirmed this PR does not duplicate planned core work - [x] I have searched GitHub for duplicate or related PRs and linked them above - [x] I have either (a) linked existing issues with `Fixes: #` / `Closes #` / `Refs #` OR (b) described the issue in-PR following the relevant issue template - [x] I have not referenced internal/instance-local Paperclip issues or links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip` URLs) - [x] My branch name describes the change (e.g. `docs/...`, `fix/...`) and contains no internal Paperclip ticket id or instance-derived details - [x] I have run tests locally and they pass - [x] I have added or updated tests where applicable - [x] I have updated relevant documentation to reflect my changes - [x] I have considered and documented any risks above - [ ] All Paperclip CI gates are green - [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups - [x] I will address all Greptile and reviewer comments before requesting merge 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
@paperclipai/adapter-utils
Shared utilities for Paperclip adapters: process spawning, environment injection, sandbox/SSH transport, workspace sync, and the round-trip helpers that move code between the local execution-workspace cwd and wherever the agent actually runs.
For the adapter-author guide see
docs/adapters/creating-an-adapter.md
and the in-repo notes at packages/adapters/AUTHORING.md.
Sandbox bridge deadlines
Command-managed bridge control operations (queue reads, input delivery, setup, and cleanup) have a host-enforced deadline of at most 30 seconds per shell command. A shorter configured timeout still applies. These operations cannot inherit the agent run's hours-long lifetime or wait forever on a provider that ignores its timeout. Long-lived agent session commands keep their own limits.
A control timeout reports a transport failure. It does not prove that the remote command stopped and does not replay an uncertain write. The process session closes failed input delivery and uses its existing shutdown path; normal execution settlement must still verify termination.
Native archive transfer deadlines
Native syncIn and syncOut calls accept an optional minimumTimeoutMs budget. The
server validates this budget and extends the worker RPC deadline. Providers can
honor this field for file transfers without changing their configuration. Daytona
uses the larger of this minimum and its configured timeout. Other providers keep
their existing behavior. The minimum is limited to 30 minutes and does not change
sandbox lifetimes, stored settings or the timeout for other commands.
The remote-workspace archive path uses the verified capture size for downloads and the local archive size for uploads. Large archives get one second per MiB plus 60 seconds, capped at 30 minutes. Small archives keep the existing provider timeout when that calculation is no greater than five minutes. Archive size, checksum, confinement and host space checks still apply.
An exact retained-sandbox resume keeps its recorded provider timeout and RPC overhead. It uses the normal one-minute fallback only when no timeout was recorded. A five-minute cold restore must not be cut off by that fallback. Resume still targets the recorded allocation and does not acquire a replacement.
No-remote-git contract
The local execution-workspace cwd is the only persistence boundary across runs. No adapter may depend on a git remote for cross-run state.
Adapters that run the agent on a different host should use the SSH round-trip
helpers in src/ssh.ts:
prepareWorkspaceForSshExecution({ spec, localDir, remoteDir })— bundles the local cwd (tracked files, dirty edits, untracked additions, and the git history needed to reconstruct it) toremoteDirbefore the run starts. Runs with nogit remoteconfigured.restoreWorkspaceFromSshExecution({ spec, localDir, remoteDir, ... })— syncs the remote cwd back intolocalDirafter the run, including any new commits the agent created. Also runs with nogit remoteconfigured.
prepareRemoteManagedRuntime in
src/remote-managed-runtime.ts wraps both
calls for adapters that want a per-run remote workspace and an automatic
restoreWorkspace() finally hook.
The invariant is pinned by the no-remote-git contract case in
src/ssh-fixture.test.ts, which asserts that a
remote-only commit propagates to the local worktree through the
prepare → restore round-trip with no git remote configured at any point. Do
not regress that test.