Tasks: the tmux session name the-loop records and posts is the name tmux gave the session

Phase 3 of 3 (requirements → design → tasks). Derived from the approved design.md. TDD per task (tdd.mode: standard): the test is written first and watched red before the production change.

Task list

• [x] 1. tmux_session_name() — mirror tmux's session_check_name()

  • Add the pure helper to cli/the_loop/sessions/registry.py (./: → _), export it from the_loop.sessions.
  • Depends on: none
  • Requirements: R1 (AC1, AC2)
  • Test: pytest cli/tests/test_tmux_runner.py -k TestTmuxSessionName — plain names pass through, dotted/colon'd names are rewritten, idempotent (red→green)

• [x] 2. TmuxRunner.target_for mints only names tmux keeps

  • Apply the helper; update the docstring to say why (tmux rewrites them, and re-parses them as session:window.pane on the way back).
  • Depends on: 1
  • Requirements: R1 (AC1, AC2)
  • Test: pytest cli/tests/test_tmux_runner.py -k "target_for" — test_target_for_strips_tmux_target_syntax and test_target_for_unchanged_for_plain_slugs (red→green)

• [x] 3. Session.__post_init__ normalises tmux_target

  • Every construction path (from_dict on a legacy record, the dispatcher's direct construction, tests) lands on the name tmux uses; "" stays "".
  • Depends on: 1
  • Requirements: R2 (AC3)
  • Test: pytest cli/tests/test_tmux_runner.py -k legacy_tmux_target (red→green)

• [x] 4. The announced attach command names a session tmux can find

  • No code change expected in announce.py — the test proves the fix reaches the human-facing surface the issue is about.
  • Depends on: 3
  • Requirements: R2 (AC4)
  • Test: pytest cli/tests/test_announce.py -k real_tmux_session (red→green)

• [x] 5. Every tmux argv addresses the normalised target

  • deliver / kill / probes built from a legacy dotted record name the underscore session.
  • Depends on: 3
  • Requirements: R2 (AC5)
  • Test: pytest cli/tests/test_tmux_runner.py -k normalised_target (red→green)

• [x] 6. Security: _LOOP_TARGET_RE rejects tmux target syntax

  • Drop . from the charset (: was never in it) so the guard authorising terminate_harness to signal pane pids cannot admit a string tmux re-parses as session:window.pane.
  • Depends on: none
  • Requirements: R3 (AC6)
  • Test (negative, abuse case):pytest cli/tests/test_tmux_runner.py -k only_the_loops_own_sessions — a hand-edited loop-other.session / loop-other:0.1 is refused and no signal is sent (red→green)

• [x] 7. Security: pin the ./_ aliasing as known and non-destructive

  • Amend _clear_target's docstring so its "an occupant is always this work item's own agent" reasoning states the alias exception instead of misleading the next reader.
  • Depends on: 2
  • Requirements: R3 (AC6), design.md § Security design (abuse-case coverage)
  • Test: pytest cli/tests/test_tmux_runner.py -k aliases_dot_and_underscore (documents the alias; fails if a future change makes it destructive)

• [x] 8. Teach the stub tmux tmux's own rename

  • cli/tests/test_tmux_runner_integration.py: new-session creates name.replace('.','_').replace(':','_'); has-session/list-panes/ kill-session answer about that name.
  • Depends on: none
  • Requirements: R4 (AC8)
  • Test: the existing integration suite stays green with the stub change alone

• [x] 9. Integration test — the reporter's scenario, end to end

  • Gherkin scenario: a work item whose repo name contains a dot is spawned; the name recorded, logged and announced is the name the stub tmux created, and a second event pastes into it instead of respawning.
  • Depends on: 2, 3, 8
  • Requirements: R4 (AC7, AC8)
  • Test: pytest cli/tests/test_tmux_runner_integration.py -k dotted (red→green)

• [x] 10. Capability docs + execution log

  • docs/capabilities/interactive-sessions.md: the session-naming behaviour and its history row.
  • Depends on: 1–9
  • Requirements: all
  • Test: markdownlint clean; the-loop check issue-154 --recompute --fail-on block

• [x] 11. Full gate + PR with the reviewer briefing

  • ruff (check + format), pyright, pytest, markdownlint — the same commands the pre-commit hooks and CI run — then the PR and its briefing.
  • Depends on: 10
  • Requirements: all
  • Test: the full suite, plus the-loop check issue-154 --recompute --fail-on block

Dependency graph (DAG)

flowchart LR
  T1["1 tmux_session_name()"] --> T2["2 target_for"]
  T1 --> T3["3 Session.__post_init__"]
  T3 --> T4["4 announce"]
  T3 --> T5["5 tmux argv"]
  T6["6 _LOOP_TARGET_RE"] --> T10["10 capability docs"]
  T2 --> T7["7 alias docstring"]
  T8["8 stub tmux rename"] --> T9["9 integration scenario"]
  T2 --> T9
  T3 --> T9
  T4 --> T10
  T5 --> T10
  T7 --> T10
  T9 --> T10
  T10 --> T11["11 gate + PR"]

1 → 2 → 7, 1 → 3 → {4, 5}, 8 → 9, 6, all → 10 → 11.

Checkpoints

• After tasks 1–3: pytest cli/tests/test_tmux_runner.py — the naming unit tests are green and nothing else in the runner regressed.
• After tasks 4–7: full pytest, plus ruff/pyright on the touched files.
• After task 9: full pytest — the stub's new rename must not have broken any existing integration scenario.
• After task 10: markdownlint + the-loop check issue-154 --recompute --fail-on block.
• After task 11: the self/critic review rounds and the security review gate (security.review), recorded in execution-log.md, before the work item is marked ready.

Review comments

Appended by the-loop's record-feedback hook when a human gate approves with comments (issue-109).