# Actual Self Probe Island

> A fixture containing only a command that deliberately closes its own stdout, so closed-stream-check.py must count it as an own-probe and return NOTHING PROBED rather than re-probing shell redirection syntax. Never distributed; exists as a regression for command-position parsing. Trigger phrases - "actual self probe fixture", "redirection position regression".

- Skill: `island-dev-crew/actual-self-probe-island` (Agent Skill)
- Install (CLI): `npx skillmds@latest add island-dev-crew/actual-self-probe-island`
- Raw SKILL.md: https://api.skillmd.com/api/skills/island-dev-crew/actual-self-probe-island/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: Island-Dev-Crew (https://skillmd.com/u/island-dev-crew)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/island-dev-crew/actual-self-probe-island

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# Actual self-probe island

This command closes its own stdout in the actual gate position. Re-closing it would test the
harness, so the checker must exclude it explicitly and return 3 because nothing else ran.

- `enforced`: closed-stream-check.py reports one own-probe, zero probes, and exit 3.
- `advisory`: nothing else here is real.

```bash
python3 -c "import sys; sys.exit(0)" 1>&-   # exit 0
```