feat: default-tmux-sessions

[satyaborg]

Default tmux Sessions

Problem

An interactive devloop currently owns the invoking terminal for its entire coder and reviewer loop. Closing that terminal interrupts the run, detaching the terminal is not possible, and several concurrent devloops are difficult to identify or revisit. This hurts when a long run must continue unattended or when multiple specs are running at once across repositories.

Outcome

devloop <spec> and devloop continue create one unique, human-readable tmux session per interactive run and move the user into it. A user can detach with Ctrl-b d, close the original terminal, list the named sessions, and reattach later while the same devloop keeps running. Launching from an existing tmux client switches to the new session instead of nesting tmux. --no-tmux and non-interactive execution retain the current foreground behavior, while installation and doctor flows treat tmux as a required dependency.

Acceptance Criteria

AC1: An eligible devloop <spec> invocation outside tmux creates a new named tmux session, attaches the current terminal, and starts the loop only inside that session.
AC2: An eligible run invoked inside tmux creates a separate detached session and switches the existing client to it without nesting tmux.
AC3: A run's base session name is the normalized devloop-<repo>-<spec-slug> form, while a continued run uses the track filename as its slug source.
AC4: An occupied base session name produces the first available numeric suffix starting at -2 without attaching to the occupied session.
AC5: Detaching or disconnecting the client leaves the launched devloop running and discoverable under its allocated session name.
AC6: --no-tmux is accepted by explicit run and continue commands and preserves their existing foreground behavior without invoking tmux.
AC7: A run with non-TTY stdin or stdout preserves the existing foreground behavior without invoking tmux.
AC8: A menu-selected run creates one session after selection and passes its resolved run choices to the child without repeating the spec or PR prompts.
AC9: Explicit and menu-selected continue workflows create one new session after resolving the track and resume through the existing run_from_track behavior.
AC10: A missing tmux command makes an eligible launch fail before loop execution with actionable installation guidance.
AC11: Invalid spec or track input returns the existing validation error before any tmux session is created.
AC12: A failed new-session call exits nonzero and never falls back to a second foreground execution.
AC13: The tmux child receives the caller's working directory, current PATH, original arguments as distinct argv values, and exactly one injected --no-tmux recursion guard.
AC14: devloop spec, nightshift, status, clean, reports, doctor, and update do not enter the automatic tmux boundary, and nightshift child loops explicitly pass --no-tmux.
AC15: Both installers treat tmux as a required Homebrew formula, post-install verification checks it, and devloop doctor fails required-dependency readiness when it is absent.
AC16: Plain help, TUI help, README.md, and CONTRIBUTING.md document the tmux default, --no-tmux, required dependency, detach command, and reattach command where appropriate.
AC17: bash scripts/devloop_test.sh passes with every new project function covered and no real tmux side effect.

Review Trail

Review rounds and the final report are posted as PR comments below.

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[satyaborg]

Devloop Review Round 1

• Verdict: ACCEPT

Review 1

Verdict: ACCEPT

Acceptance matrix

Obligation	Status	Implementation evidence	Test evidence
AC1	PASS	run_command validates before delegating once to tmux_launch_session (devloop:3016-3024); the outside branch uses attached new-session with the named child (devloop:378-381).	The fake-tmux outside launch asserts new-session, -s, no -d, and no foreground execution (scripts/devloop_test.sh:541-562,609-628).
AC2	PASS	A nonempty TMUX selects detached new-session -d followed by switch-client, with no nested attach (devloop:364-375).	The inside-tmux fixture asserts detached creation, client switching, continue argv, and one recursion guard (scripts/devloop_test.sh:564-574).
AC3	PASS	tmux_session_base_name normalizes the repository basename and the supplied spec or track filename (devloop:302-319); continue callers supply the validated track (devloop:1823-1829,1989-2001).	Normalization, fallback names, run names, and both explicit and menu continue track arguments are asserted (scripts/devloop_test.sh:495-498,684-696,750-763).
AC4	PASS	tmux_allocate_session_name checks exact names and increments from -2 until free (devloop:325-336); launch uses only new-session, never attach-or-create (devloop:364-381).	Occupied base and -2 allocate -3; the launcher assertion rejects -A (scripts/devloop_test.sh:531-535,558-560).
AC5	PASS	The launcher starts the devloop child as the tmux session command and adds no cleanup or keepalive process (devloop:351-381).	The fake launcher verifies a named session and direct child command, while help and README checks verify list, detach, and reattach guidance (scripts/devloop_test.sh:541-562,85-91,116-119).
AC6	PASS	run_command and continue_command parse --no-tmux, skip the boundary, and call their existing foreground owners (devloop:1954-2004,2939-3031).	Explicit run and continue tests force interactive eligibility and assert zero launcher calls plus foreground delegation (scripts/devloop_test.sh:630-643,698-707).
AC7	PASS	devloop_tmux_interactive requires TTY stdin and stdout; otherwise run_command reaches the unchanged foreground path (devloop:298-300,3016-3031).	Separate non-TTY stdin and stdout checks reject eligibility, and a false predicate test asserts foreground run with no tmux launch (scripts/devloop_test.sh:499-500,645-657).
AC8	PASS	interactive_run_setup resolves PR mode first and serializes TUI, report, strictness, worktree, PR, shell, agents, timeout, spec, and max into one child argv (devloop:1722-1762).	The menu fixture asserts one PR prompt, one launch, resolved TUI, agent, timeout, PR, and shell values, and no foreground loop (scripts/devloop_test.sh:720-748).
AC9	PASS	Explicit and menu continue validate the track before one launch; the guarded child re-enters continue_command, which delegates to canonical run_from_track (devloop:1806-1831,1953-2004,2843-2878).	Explicit and menu-selected continue each assert one boundary call with the resolved track; foreground continue coverage exercises run_from_track (scripts/devloop_test.sh:684-707,750-763,2930-2955,3046-3050).
AC10	PASS	tmux_launch_session checks command availability before name allocation or child creation and returns actionable installation guidance (devloop:338-349).	The missing-command fixture asserts nonzero status and installer/install guidance (scripts/devloop_test.sh:598-605).
AC11	PASS	Runs call validate_spec_for_tmux, and continues call validate_track_for_run, before the launcher (devloop:1748-1762,1823-1829,1989-2004,3016-3024).	Missing spec and track cases assert the existing error and an empty launcher log (scripts/devloop_test.sh:672-682,709-718).
AC12	PASS	Both new-session branches return nonzero immediately on failure and contain no foreground fallback (devloop:364-381).	The fake new-session failure is propagated, does not switch clients, and the run-boundary failure test proves no foreground retry (scripts/devloop_test.sh:576-584,659-670).
AC13	PASS	The launcher passes -c "$PWD", an absolute env, PATH=$PATH, the runtime, and array-expanded child arguments, injecting one guard (devloop:338-378).	The fake-tmux log asserts cwd, PATH, runtime, spaces, metacharacters, and exactly one --no-tmux (scripts/devloop_test.sh:537-562,564-574).
AC14	PASS	Only run and continue entry functions call the launcher; utility dispatch remains direct, and nightshift explicitly adds --no-tmux (devloop:86-165,1722-1768,1806-1831,1953-2004,2331-2342,2921-3031).	Existing main-dispatch tests exercise menu, spec, nightshift, update, status, clean, reports, and doctor; nightshift argv explicitly includes --no-tmux (scripts/devloop_test.sh:1542-1572,1349,2028-2155,2542-2615,3044-3052).
AC15	PASS	Both installers include tmux in discovery and post-install verification, and doctor includes it in required readiness (scripts/install.sh:49-101, scripts/install.remote.sh:188-224,271-314,405-438, scripts/skill_helpers.sh:343-367).	Local and remote bootstrap fixtures assert tmux installation; doctor passes with tmux and fails without it (scripts/devloop_test.sh:1915-1916,2017-2206,2330-2354,2542-2615).
AC16	PASS	Plain help, TUI help, README, and CONTRIBUTING document the default, required dependency, override, and applicable detach/reattach workflow (devloop:183-228,231-268, README.md:27-53, CONTRIBUTING.md:11-14).	Help, TUI, README, and CONTRIBUTING string assertions cover tmux, --no-tmux, Ctrl-b d, and tmux attach -t (scripts/devloop_test.sh:70-91,113-123,451-468).
AC17	PASS	New behavior is isolated in sourceable functions and tmux execution is injectable through PATH and function overrides.	bash scripts/devloop_test.sh passed on review, ending with ok - 100% project function coverage; the tmux block uses only a fake executable (scripts/devloop_test.sh:502-529,3354).
F1	PASS	Missing tmux returns before building or executing the child (devloop:338-349).	Missing-tmux and launch-failure tests assert nonzero status, guidance, and no foreground retry (scripts/devloop_test.sh:598-605,659-670).
F2	PASS	Exact-name allocation chooses the first free suffix; no code path uses new-session -A (devloop:325-381).	The collision fixture allocates -3 after base and -2, and the launch log asserts absence of -A (scripts/devloop_test.sh:531-535,558-560).
F3	PASS	Spec and track validators run before all eligible tmux calls (devloop:1748-1762,1823-1829,1989-2004,3016-3024).	Invalid spec and track tests assert validation output and no launcher call (scripts/devloop_test.sh:672-682,709-718).
F4	PASS	Failed creation returns immediately from either inside or outside branch, with no retry (devloop:364-381).	The injected creation failure returns nonzero, reports the allocated session, skips switching, and the caller test rejects foreground retry (scripts/devloop_test.sh:576-584,659-670).
F5	PASS	Switch failure reports the allocated name and manual switch and attach commands, then returns without killing or relaunching (devloop:369-374).	The switch-failure fixture asserts all recovery guidance and exactly one new-session (scripts/devloop_test.sh:586-596).
F6	PASS	Noninteractive eligibility fails unless both standard streams are TTYs, leaving foreground ownership unchanged (devloop:298-300,3016-3031).	Non-TTY stdin, non-TTY stdout, and foreground delegation are covered (scripts/devloop_test.sh:499-500,645-657).
F7	PASS	Both parsers consume --no-tmux as control state and exclude it from normal run or track semantics (devloop:1953-2004,2921-3031).	Interactive-forced run and continue tests assert no launcher invocation and equivalent foreground arguments (scripts/devloop_test.sh:630-643,698-707).
F8	PASS	Devloop launches as the tmux session command and performs no detach cleanup, so tmux owns persistence (devloop:364-381).	The named-session argv test plus help and README detach/reattach assertions verify the intended tmux lifecycle contract (scripts/devloop_test.sh:537-562,85-91,116-119).
F9	PASS	The parent injects --no-tmux into run or continue child argv, and both child parsers bypass wrapping when it is present (devloop:351-354,1953-2004,2975-3025).	Outside and inside launcher logs each contain exactly one guard; separate guarded run and continue tests prove re-entry bypass (scripts/devloop_test.sh:561,574,630-643,698-707).
F10	PASS	Child arguments are Bash array elements passed directly after tmux --, without eval or sh -c (devloop:343-378).	Arguments containing spaces and shell metacharacters remain distinct in the fake log and do not create the marker file (scripts/devloop_test.sh:540-562).
F11	PASS	An absolute env executable sets the caller's current PATH for the direct child command (devloop:357-378).	The fake log asserts the exact current PATH assignment and resolved runtime argv (scripts/devloop_test.sh:552-556).
F12	PASS	The tmux command ends at the devloop child argv and adds no shell, prompt, sleep, or keepalive (devloop:351-381).	The launcher test asserts no shell wrapper; the direct argv layout contains only env, PATH, runtime, guard, and original arguments (scripts/devloop_test.sh:548-562).
F13	PASS	nightshift_run_spec always invokes child loops with --plain --no-tmux --no-shell (devloop:2331-2342).	Nightshift orchestration asserts all five child invocations include the headless --no-tmux flag set (scripts/devloop_test.sh:1347-1351).
I1	PASS	Each eligible caller returns immediately after one tmux_launch_session; that helper issues one new-session for the allocated name (devloop:1748-1762,1823-1829,1989-2004,3016-3024,364-381).	Explicit and menu boundaries assert one launch with no foreground loop; switch failure separately asserts one creation (scripts/devloop_test.sh:609-628,684-696,720-764,595).
I2	PASS	Allocation never mutates occupied sessions, and launcher operations are limited to listing, fresh creation, and client switching (devloop:325-381).	Collision and argv tests prove exact lookup, numeric allocation, and absence of -A; no fake operation attaches to, replaces, or kills an existing session (scripts/devloop_test.sh:531-560).
I3	PASS	Automatic wrapping is called only from explicit/menu run and continue; nightshift opts out and utilities keep their prior dispatch (devloop:86-165,1722-1768,1806-1831,1953-2004,2331-2342,2921-3031).	Main dispatch coverage plus the nightshift argv assertion exercise the excluded workflows without a tmux boundary (scripts/devloop_test.sh:1349,1542-1572,2028-2155,2542-2615,3044-3052).
I4	PASS	The child guard returns execution to the existing run_devloop and run_from_track owners without moving loop, worktree, reporting, or exit logic into tmux helpers (devloop:2843-2878,3027-3031).	Guarded foreground run/continue tests and the existing end-to-end loop/continue suite pass (scripts/devloop_test.sh:630-657,698-707,2867-2955,3014-3055).
I5	PASS	User-controlled values stay in arrays and are expanded as "${child[@]}"; no assembled shell command is used (devloop:343-378).	Space and metacharacter cases remain separate fake-tmux argv entries and are not evaluated (scripts/devloop_test.sh:540-562).
I6	PASS	Tmux calls are isolated behind a PATH-resolved command suitable for a fixture.	The suite prepends its fake tmux before launcher tests, restores PATH afterward, and the full suite passes without a real-session operation (scripts/devloop_test.sh:502-529,766-768).

Engineering quality matrix

Area	Status	Evidence
Correctness	PASS	Validation precedes launch, inside and outside tmux paths are distinct, failures do not fall back, and the full regression suite passes.
Test quality	PASS	Tests cover naming, collision allocation, direct argv, recursion guards, both tmux contexts, failure recovery, explicit/menu run and continue, installers, doctor, help, documentation, and retain 100% project-function coverage.
Maintainability	PASS	Tmux behavior is concentrated in small helpers, while entry points only validate, serialize resolved choices, and delegate.
Architecture boundaries	PASS	Existing run_devloop, run_from_track, menu selection, nightshift, installer, and doctor ownership remains intact across the new process boundary.
Simplicity	PASS	The solution uses one public recursion flag and direct tmux commands without polling, PID state, generated scripts, cleanup orchestration, or compatibility layers.
Security	PASS	Paths and user arguments remain distinct argv entries, session names are normalized, and no shell interpolation, eval, or sh -c is introduced.
Operational safety	PASS	Fresh names avoid session reuse, creation and switch failures are recoverable, existing sessions are never killed, and tests cannot reach a real tmux server through the fixture path.

Review flags

• Silent decision: absent - Session lifetime, interactive eligibility, naming sources, prompt timing, collision races, and direct argv choices are recorded in the spec and track.
• Scope drift: absent - Every changed runtime, installer, doctor, documentation, and test file is named by the implementation map and supports a listed obligation.
• Missing test: absent - Changed behavior has targeted fake-tmux, boundary, installer, doctor, help, documentation, and full-suite regression evidence.

Findings

None

Missing tests

• None

Fix instructions

None

Notes

• The prior review path named in the request was absent before this review, so there were no earlier findings to compare.
• Review verification passed: bash scripts/devloop_test.sh, Bash syntax checks, ShellCheck, and git diff --check main...HEAD.
• Real attach and detach are intentionally proven through tmux's documented command contract and fake argv assertions, preserving invariant I6.

[satyaborg]

Devloop Final Report

Field	Value
Final status	accepted
Pass count	1 / 5
Final verdict	ACCEPT
PR URL	#88
Branch	feat/default-tmux-sessions

Acceptance Matrix Summary

Acceptance matrix

Obligation	Status	Implementation evidence	Test evidence
AC1	PASS	run_command validates before delegating once to tmux_launch_session (devloop:3016-3024); the outside branch uses attached new-session with the named child (devloop:378-381).	The fake-tmux outside launch asserts new-session, -s, no -d, and no foreground execution (scripts/devloop_test.sh:541-562,609-628).
AC2	PASS	A nonempty TMUX selects detached new-session -d followed by switch-client, with no nested attach (devloop:364-375).	The inside-tmux fixture asserts detached creation, client switching, continue argv, and one recursion guard (scripts/devloop_test.sh:564-574).
AC3	PASS	tmux_session_base_name normalizes the repository basename and the supplied spec or track filename (devloop:302-319); continue callers supply the validated track (devloop:1823-1829,1989-2001).	Normalization, fallback names, run names, and both explicit and menu continue track arguments are asserted (scripts/devloop_test.sh:495-498,684-696,750-763).
AC4	PASS	tmux_allocate_session_name checks exact names and increments from -2 until free (devloop:325-336); launch uses only new-session, never attach-or-create (devloop:364-381).	Occupied base and -2 allocate -3; the launcher assertion rejects -A (scripts/devloop_test.sh:531-535,558-560).
AC5	PASS	The launcher starts the devloop child as the tmux session command and adds no cleanup or keepalive process (devloop:351-381).	The fake launcher verifies a named session and direct child command, while help and README checks verify list, detach, and reattach guidance (scripts/devloop_test.sh:541-562,85-91,116-119).
AC6	PASS	run_command and continue_command parse --no-tmux, skip the boundary, and call their existing foreground owners (devloop:1954-2004,2939-3031).	Explicit run and continue tests force interactive eligibility and assert zero launcher calls plus foreground delegation (scripts/devloop_test.sh:630-643,698-707).
AC7	PASS	devloop_tmux_interactive requires TTY stdin and stdout; otherwise run_command reaches the unchanged foreground path (devloop:298-300,3016-3031).	Separate non-TTY stdin and stdout checks reject eligibility, and a false predicate test asserts foreground run with no tmux launch (scripts/devloop_test.sh:499-500,645-657).
AC8	PASS	interactive_run_setup resolves PR mode first and serializes TUI, report, strictness, worktree, PR, shell, agents, timeout, spec, and max into one child argv (devloop:1722-1762).	The menu fixture asserts one PR prompt, one launch, resolved TUI, agent, timeout, PR, and shell values, and no foreground loop (scripts/devloop_test.sh:720-748).
AC9	PASS	Explicit and menu continue validate the track before one launch; the guarded child re-enters continue_command, which delegates to canonical run_from_track (devloop:1806-1831,1953-2004,2843-2878).	Explicit and menu-selected continue each assert one boundary call with the resolved track; foreground continue coverage exercises run_from_track (scripts/devloop_test.sh:684-707,750-763,2930-2955,3046-3050).
AC10	PASS	tmux_launch_session checks command availability before name allocation or child creation and returns actionable installation guidance (devloop:338-349).	The missing-command fixture asserts nonzero status and installer/install guidance (scripts/devloop_test.sh:598-605).
AC11	PASS	Runs call validate_spec_for_tmux, and continues call validate_track_for_run, before the launcher (devloop:1748-1762,1823-1829,1989-2004,3016-3024).	Missing spec and track cases assert the existing error and an empty launcher log (scripts/devloop_test.sh:672-682,709-718).
AC12	PASS	Both new-session branches return nonzero immediately on failure and contain no foreground fallback (devloop:364-381).	The fake new-session failure is propagated, does not switch clients, and the run-boundary failure test proves no foreground retry (scripts/devloop_test.sh:576-584,659-670).
AC13	PASS	The launcher passes -c "$PWD", an absolute env, PATH=$PATH, the runtime, and array-expanded child arguments, injecting one guard (devloop:338-378).	The fake-tmux log asserts cwd, PATH, runtime, spaces, metacharacters, and exactly one --no-tmux (scripts/devloop_test.sh:537-562,564-574).
AC14	PASS	Only run and continue entry functions call the launcher; utility dispatch remains direct, and nightshift explicitly adds --no-tmux (devloop:86-165,1722-1768,1806-1831,1953-2004,2331-2342,2921-3031).	Existing main-dispatch tests exercise menu, spec, nightshift, update, status, clean, reports, and doctor; nightshift argv explicitly includes --no-tmux (scripts/devloop_test.sh:1542-1572,1349,2028-2155,2542-2615,3044-3052).
AC15	PASS	Both installers include tmux in discovery and post-install verification, and doctor includes it in required readiness (scripts/install.sh:49-101, scripts/install.remote.sh:188-224,271-314,405-438, scripts/skill_helpers.sh:343-367).	Local and remote bootstrap fixtures assert tmux installation; doctor passes with tmux and fails without it (scripts/devloop_test.sh:1915-1916,2017-2206,2330-2354,2542-2615).
AC16	PASS	Plain help, TUI help, README, and CONTRIBUTING document the default, required dependency, override, and applicable detach/reattach workflow (devloop:183-228,231-268, README.md:27-53, CONTRIBUTING.md:11-14).	Help, TUI, README, and CONTRIBUTING string assertions cover tmux, --no-tmux, Ctrl-b d, and tmux attach -t (scripts/devloop_test.sh:70-91,113-123,451-468).
AC17	PASS	New behavior is isolated in sourceable functions and tmux execution is injectable through PATH and function overrides.	bash scripts/devloop_test.sh passed on review, ending with ok - 100% project function coverage; the tmux block uses only a fake executable (scripts/devloop_test.sh:502-529,3354).
F1	PASS	Missing tmux returns before building or executing the child (devloop:338-349).	Missing-tmux and launch-failure tests assert nonzero status, guidance, and no foreground retry (scripts/devloop_test.sh:598-605,659-670).
F2	PASS	Exact-name allocation chooses the first free suffix; no code path uses new-session -A (devloop:325-381).	The collision fixture allocates -3 after base and -2, and the launch log asserts absence of -A (scripts/devloop_test.sh:531-535,558-560).
F3	PASS	Spec and track validators run before all eligible tmux calls (devloop:1748-1762,1823-1829,1989-2004,3016-3024).	Invalid spec and track tests assert validation output and no launcher call (scripts/devloop_test.sh:672-682,709-718).
F4	PASS	Failed creation returns immediately from either inside or outside branch, with no retry (devloop:364-381).	The injected creation failure returns nonzero, reports the allocated session, skips switching, and the caller test rejects foreground retry (scripts/devloop_test.sh:576-584,659-670).
F5	PASS	Switch failure reports the allocated name and manual switch and attach commands, then returns without killing or relaunching (devloop:369-374).	The switch-failure fixture asserts all recovery guidance and exactly one new-session (scripts/devloop_test.sh:586-596).
F6	PASS	Noninteractive eligibility fails unless both standard streams are TTYs, leaving foreground ownership unchanged (devloop:298-300,3016-3031).	Non-TTY stdin, non-TTY stdout, and foreground delegation are covered (scripts/devloop_test.sh:499-500,645-657).
F7	PASS	Both parsers consume --no-tmux as control state and exclude it from normal run or track semantics (devloop:1953-2004,2921-3031).	Interactive-forced run and continue tests assert no launcher invocation and equivalent foreground arguments (scripts/devloop_test.sh:630-643,698-707).
F8	PASS	Devloop launches as the tmux session command and performs no detach cleanup, so tmux owns persistence (devloop:364-381).	The named-session argv test plus help and README detach/reattach assertions verify the intended tmux lifecycle contract (scripts/devloop_test.sh:537-562,85-91,116-119).
F9	PASS	The parent injects --no-tmux into run or continue child argv, and both child parsers bypass wrapping when it is present (devloop:351-354,1953-2004,2975-3025).	Outside and inside launcher logs each contain exactly one guard; separate guarded run and continue tests prove re-entry bypass (scripts/devloop_test.sh:561,574,630-643,698-707).
F10	PASS	Child arguments are Bash array elements passed directly after tmux --, without eval or sh -c (devloop:343-378).	Arguments containing spaces and shell metacharacters remain distinct in the fake log and do not create the marker file (scripts/devloop_test.sh:540-562).
F11	PASS	An absolute env executable sets the caller's current PATH for the direct child command (devloop:357-378).	The fake log asserts the exact current PATH assignment and resolved runtime argv (scripts/devloop_test.sh:552-556).
F12	PASS	The tmux command ends at the devloop child argv and adds no shell, prompt, sleep, or keepalive (devloop:351-381).	The launcher test asserts no shell wrapper; the direct argv layout contains only env, PATH, runtime, guard, and original arguments (scripts/devloop_test.sh:548-562).
F13	PASS	nightshift_run_spec always invokes child loops with --plain --no-tmux --no-shell (devloop:2331-2342).	Nightshift orchestration asserts all five child invocations include the headless --no-tmux flag set (scripts/devloop_test.sh:1347-1351).
I1	PASS	Each eligible caller returns immediately after one tmux_launch_session; that helper issues one new-session for the allocated name (devloop:1748-1762,1823-1829,1989-2004,3016-3024,364-381).	Explicit and menu boundaries assert one launch with no foreground loop; switch failure separately asserts one creation (scripts/devloop_test.sh:609-628,684-696,720-764,595).
I2	PASS	Allocation never mutates occupied sessions, and launcher operations are limited to listing, fresh creation, and client switching (devloop:325-381).	Collision and argv tests prove exact lookup, numeric allocation, and absence of -A; no fake operation attaches to, replaces, or kills an existing session (scripts/devloop_test.sh:531-560).
I3	PASS	Automatic wrapping is called only from explicit/menu run and continue; nightshift opts out and utilities keep their prior dispatch (devloop:86-165,1722-1768,1806-1831,1953-2004,2331-2342,2921-3031).	Main dispatch coverage plus the nightshift argv assertion exercise the excluded workflows without a tmux boundary (scripts/devloop_test.sh:1349,1542-1572,2028-2155,2542-2615,3044-3052).
I4	PASS	The child guard returns execution to the existing run_devloop and run_from_track owners without moving loop, worktree, reporting, or exit logic into tmux helpers (devloop:2843-2878,3027-3031).	Guarded foreground run/continue tests and the existing end-to-end loop/continue suite pass (scripts/devloop_test.sh:630-657,698-707,2867-2955,3014-3055).
I5	PASS	User-controlled values stay in arrays and are expanded as "${child[@]}"; no assembled shell command is used (devloop:343-378).	Space and metacharacter cases remain separate fake-tmux argv entries and are not evaluated (scripts/devloop_test.sh:540-562).
I6	PASS	Tmux calls are isolated behind a PATH-resolved command suitable for a fixture.	The suite prepends its fake tmux before launcher tests, restores PATH afterward, and the full suite passes without a real-session operation (scripts/devloop_test.sh:502-529,766-768).

Engineering Quality Summary

Engineering quality matrix

Area	Status	Evidence
Correctness	PASS	Validation precedes launch, inside and outside tmux paths are distinct, failures do not fall back, and the full regression suite passes.
Test quality	PASS	Tests cover naming, collision allocation, direct argv, recursion guards, both tmux contexts, failure recovery, explicit/menu run and continue, installers, doctor, help, documentation, and retain 100% project-function coverage.
Maintainability	PASS	Tmux behavior is concentrated in small helpers, while entry points only validate, serialize resolved choices, and delegate.
Architecture boundaries	PASS	Existing run_devloop, run_from_track, menu selection, nightshift, installer, and doctor ownership remains intact across the new process boundary.
Simplicity	PASS	The solution uses one public recursion flag and direct tmux commands without polling, PID state, generated scripts, cleanup orchestration, or compatibility layers.
Security	PASS	Paths and user arguments remain distinct argv entries, session names are normalized, and no shell interpolation, eval, or sh -c is introduced.
Operational safety	PASS	Fresh names avoid session reuse, creation and switch failures are recoverable, existing sessions are never killed, and tests cannot reach a real tmux server through the fixture path.

Implementation Summary

• Final branch: feat/default-tmux-sessions
• Final commit: 7632883
• Commit message: feat: default-tmux-sessions

Commit References

• pass 1 7632883 feat: default-tmux-sessions (CONTRIBUTING.md, README.md, devloop, scripts/devloop_test.sh, scripts/install.remote.sh, scripts/install.sh, scripts/skill_helpers.sh)

Tests Run

• Verification hook log: not configured
• Review test evidence: see the acceptance matrix summary above.

Residual Risk

• No blocking residual risk was recorded by the final review.