From f8a007258616fbb4228223641eb5aad281ef4d64 Mon Sep 17 00:00:00 2001
From: Julian Noble <julian@precisium.com.au>
Date: Tue, 21 Jul 2026 10:08:34 +1000
Subject: [PATCH] Document punkshell stdin script mode

Clarify that ad-hoc working-tree snippets should use bin/punk91 src script rather than live src shell mode.

Assisted-by: harness=pi; primary-model=unknown; api-location=unknown
---
 AGENTS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/AGENTS.md b/AGENTS.md
index 10dcf40e..28c6ae91 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -96,6 +96,7 @@ When the user requests a durable behavior change, record it here or in the relev
 - cmd.exe PATH truncation (this machine, and any Windows machine with a heavily populated PATH): cmd.exe truncates a long PATH, so a tool that resolves fine in PowerShell may be "not found" when invoked via `cmd.exe /c`. Use absolute executable paths inside any `cmd /c` command line, and prefer PowerShell-native invocation unless a console host is specifically required (e.g. hidden-console test harnesses). If a tool is missing only under cmd.exe, suspect truncation before absence.
 - Agent-authored text is plain ASCII by default: no em/en dashes, curly quotes, arrow or ellipsis characters, or other typographic Unicode - use ASCII equivalents (" - ", straight quotes, "->", "..."). This applies with extra force to outward-bound artifacts (ticket drafts, bug reports, emails, commit messages, anything likely to be pasted into an external system): those must be pure ASCII, verified before handover (e.g. grep for `[^\x00-\x7F]`). Legitimate exceptions: content whose subject matter is itself non-ASCII (encoding/Unicode/ANSI-art test data, or documentation demonstrating such behaviour), verbatim quotes of existing material, and cases where the user explicitly requests non-ASCII. Existing files are not to be bulk-retrofitted - the rule governs newly written text.
 - Tcl has no `-e`/`-c` one-liner flag (a reflex agents carry over from perl/python/node). Stock `tclsh`/`tclsh86`/`tclsh90` recognise only `-encoding name` as a leading option; any other argument starting with `-` is NOT treated as a script file - all arguments land in `$argv` and tclsh reads commands from stdin. On a console that hangs forever at an interactive prompt; with piped/redirected stdin it exits 0 having silently ignored the supposed one-liner and executed stdin instead. (The punk kits differ: they treat `-e` as a script filename and error out immediately - no hang, but still no one-liner.) To run ad-hoc Tcl: write a temp `.tcl` file and run `tclsh path/to/file.tcl`, or pipe the script to stdin (`echo 'puts hi' | tclsh`, or a bash heredoc). Defensive habit regardless: when exec'ing tclsh non-interactively, redirect stdin (`</dev/null`, `< NUL`) so a mis-invocation exits at EOF instead of hanging.
+- For ad-hoc punkshell scripts that need working-tree modules, use `bin/punk91 src script` for stdin scripts or `bin/punk91 src script path/to/file.tcl` for script files. Do not use `bin/punk91 src` for piped/redirected snippets: `src` alone starts the live shell on the repo source tree and may execute stdin input but then remain in shell/eof handling instead of exiting cleanly. Keep `src` before `script` so the working-tree modules are loaded.
 - VCS ignore rules are dual-tracked (git + fossil). An agent that changes ignore rules in one VCS must make the equivalent change in the other in the same work unit: `.gitignore` is the canonical statement of intent and `.fossil-settings/ignore-glob` is hand-derived from it, never the reverse - so a `.gitignore` edit includes deriving the ignore-glob translation, and an ignore-glob-only edit is wrong unless it is purely catching up to `.gitignore`. Fossil globs differ semantically (no negation - tracked exceptions need explicit `fossil add`; case-sensitive; `*` crosses `/`): translate per the derivation rules in `.fossil-settings/AGENTS.md` and run its verification checks before committing.
 - Throwaway fossil repositories (test/experiment repos an agent creates, e.g. in a session scratchpad) must not register in the user's real global fossil config-db: `fossil init`/`fossil open` write persistent `repo:`/`ckout:` rows into `%LOCALAPPDATA%\_fossil`, which is the enumeration source for `dev projects.work` project discovery (G-016/G-017). Set `FOSSIL_HOME` to a disposable scratch directory for the duration of such fossil commands (both fossil and `punk::repo::fossil_get_configdb` honour it first). If pollution has already occurred: `fossil all ignore <repo-path>`, delete the directory, then any `fossil all` command prunes the orphaned `ckout:` row.
 - Fossil checkout branch discipline: in fossil, `tip` means the newest check-in on ANY branch - not the trunk tip. A `fossil open ... tip` or `fossil update tip` run shortly after an upstream feature-branch commit silently parks the checkout on that branch, and every later plain `fossil update` keeps following it. When opening or refreshing any fossil checkout (including reference checkouts such as `TEMP_REFERENCE/tcl9`), name the branch explicitly (`fossil update trunk`), never `tip`, and confirm the `tags:` line of `fossil status` shows the intended branch afterwards.