chore(agents): use dsh-nu from NUR (#475)

agents/global-rules.md

@@ -143,21 +143,20 @@ For an impactful change, follow these steps in order, scaled to its risk:
   need authorization.
 - Never block a turn on CI, whatever its expected duration. After a push, report the head revision
   and the checks that started. Start a watch on the resolved run as a background job
-  (`gh run watch <id> --exit-status`, or `gh pr checks <pr> --watch` once checks exist) following
-  Keep every turn steerable under Communication; collect and report the result when it finishes. Do
+  (`gh run watch <id> --exit-status`, or `gh pr checks <pr> --watch` once checks exist), and collect
+  and report the result when it finishes. Keep the turn steerable meanwhile (see Communication); do
   not estimate the run's duration or wait it out because it looks short.
 - Create forks with only the default branch (`gh repo fork --default-branch-only`); the task adds
   its own development branch.
 
 ## Environment and shell
 
+- Shell syntax guidance belongs to the active shell plugin or project docs; these rules keep only
+  cross-agent safety and operational constraints.
 - NixOS is non-FHS: agents MUST NOT assume FHS paths or install imperatively (`apt`, `nix-env`,
   `nix profile install`, global `npm`/`pip`). Use `nix shell nixpkgs#<pkg> -c <cmd>` or `nix run`
   for one-off tools, and the project's existing toolchain (e.g. its flake, `uv`, `pnpm`) for its
   dependencies; ask before creating a flake or installing another way.
-- The user's interactive shell is **nushell**, and shell work defaults to Nushell. Bash is only
-  started from within nushell, occasionally, for tasks nushell can't do. Put shell env, aliases, and
-  per-session secrets in the Nushell config, not in `bashrc`/`zshrc`.
 - Use `gh` for authorized GitHub operations; keep SSH for GitHub Git remotes and make sure the
   Nix-managed `~/.ssh/config` is used.
 - Code layout: `~/codes` = personal, `~/work` = work code, `~/src/<repo>` = source checkouts.
@@ -175,13 +174,10 @@ For an impactful change, follow these steps in order, scaled to its risk:
 - Prefer native tool options to reduce output at the source, and the native read, grep, glob, write,
   and edit tools over their shell equivalents. A single shell dispatch is for genuinely shell work
   (git, ssh, nix, remote commands).
-- Use the shell the runtime provides, in its own dialect, and never hand a command string to another
-  shell (`bash -c`, `sh -c`). Default shell work to Nushell. Compose multi-step work with code-mode
-  (PTC) for orchestration, returned tool results, loops, and state across calls; otherwise use
-  Nushell's structured pipelines when available, Python for general local processing, one runtime
-  invocation (`python -c '<code>'`, `nu -c '<code>'`), or a script written with the write tool. Set
-  the tool's working-directory parameter instead of `cd`. A remote command usually runs under a
-  POSIX shell: keep it to one runtime invocation or a copied script.
+- Use the shell the runtime provides; dsh-nu fails closed rather than substituting another shell.
+  For genuinely shell work use the available runtime, `python -c '<code>'` for complex local
+  processing, or a script written with the write tool. A remote command usually runs under a POSIX
+  shell: keep it to one invocation or a copied script.
 - Commands MUST NOT block: disable pagers and interactive prompts (confirm with the user instead of
   making a command interactive, e.g. `rm -i`), avoid commands that wait on stdin or never exit, and
   bound waits and retries with a total time limit the waiting command enforces itself, not an outer
@@ -192,9 +188,9 @@ For an impactful change, follow these steps in order, scaled to its risk:
   when it fires; any poll MUST check the condition and exit as soon as it holds. A retry or protocol
   backoff MAY wait at most 5 seconds per attempt, never longer and never as a progress wait. Make a
   readiness check fail on an error response (e.g. `curl --fail`), not only on a refused connection.
-- When output is filtered or trimmed, agents MUST keep the producer's own exit status: capture
-  output and status together (`| complete` in Nushell, `set -o pipefail` in a POSIX shell) or in
-  code, and never report a successful filter as a successful command.
+- When output is filtered or trimmed, agents MUST keep the producer's own exit status. Capture
+  output and status together with the runtime's mechanism or in code, and never report a successful
+  filter as a successful command.
 - Start servers and watchers as runtime background jobs with their output going to logs; capture the
   job handle or PID when starting them, never by matching `ps` output or a shell `&`.
 
@@ -203,7 +199,7 @@ For an impactful change, follow these steps in order, scaled to its risk:
 - Scripts added to a project MUST follow its language and target environment, defaulting to Python
   unless the project ecosystem or data format has a clearer supported runtime.
 - Script files agents create or modify, including temporary ones, MUST pass the available checks
-  (e.g. `shellcheck`, `nu-check`, `py_compile`, `tsc --noEmit`); report any unavailable check.
+  (e.g. `py_compile`, `tsc --noEmit`); report any unavailable check.
 
 ## Communication
 

flake.lock

@@ -1027,11 +1027,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1792297214,
-        "narHash": "sha256-zRPv4X2ywq1gcBwbI2qCS7pur7oneze2eQAUPpODlnw=",
+        "lastModified": 1792330633,
+        "narHash": "sha256-ICHmCPVtJxn5E2yNzF2+c++AajG4G4YEESxmwbjqVX4=",
         "owner": "ryan4yin",
         "repo": "nur-packages",
-        "rev": "1a845e77e62f8a2a1653d994e60981c0684087f2",
+        "rev": "b96977d219e9b2dcc30c67f89a698ea961fb68c3",
         "type": "github"
       },
       "original": {

home/base/tui/agents/dsh.md

@@ -53,27 +53,25 @@ on, `$DSH_AGENTS_HOME/AGENTS.md` — so no patch row is needed; identical conten
 
 ## Nushell-only shell
 
-`nur-ryan4yin`'s `dsh.withPlugins [ ...dsh-nushell-only ]` replaces the two first-party shell
-providers with Nushell: every `ctx.shell` consumer (model shell tools, background jobs, hook
-bridges, in-process callers) runs `nu --no-config-file -c`, and a command that hands execution to
-another shell is refused before it spawns. The plugin adds Nushell rules and a syntax guide, and
-rewrites the shell-tool descriptions, so the model is told what actually runs. `nu` comes from the
-NUR package, so it does not depend on `PATH`.
+`nur-ryan4yin`'s `dsh.withPlugins [ ...dsh-nu ]` replaces the two first-party shell providers with
+Nushell: every `ctx.shell` consumer (model shell tools, background jobs, hook bridges, in-process
+callers) runs `nu --no-config-file -c`, and a command that hands execution to another shell is
+refused before it spawns. The plugin adds Nushell rules and a syntax guide, and rewrites the
+shell-tool descriptions, so the model is told what actually runs. `nu` comes from the NUR package,
+so it does not depend on `PATH`.
 
-The source is the `develop` branch of ryan4yin's fork carrying the reviewed patch set (Nu-builtin
-denial facts, test-harness fixes, the `find` hint, persistent-terminal scoping), pinned by
-`fetchFromGitHub` and `hashes.json` in `nur-packages`; nix-config locks that package set in its
-`flake.lock`. `dsh.withPlugins` wraps the binary: each invocation gets a generated `--patch <file>`
-overlay after the profile layer, while `dsh plugin` stays untouched. No `$DSH_HOME/cordis.patch.yml`
-is written, so there is no home-layer state to resolve or roll back. Boundaries: preset rows that
-spawn a shell themselves (`custom-bash.mjs`, `persistent-shell`) bypass `ctx.shell`. So does
-`@deepseek-ai/dsh-experimental-terminal-bundle`: its `terminal_*` tools use a separate
-`ctx.terminals` seam and run the platform shell (bash on the POSIX hosts this repository manages),
-so they coexist with this plugin but stay outside the Nushell-only guarantee — keep the bundle off
-for a strict Nu-only machine (the fork's `--with-terminal-bundle` integration run covers the
-coexistence). Bash hooks now run under Nushell and need rewriting; remote hosts still run their own
-POSIX shell. Rollback: install plain `dsh` or pass an empty plugin list; there is no home file to
-delete. Tested on Linux; the same package also builds for Darwin, where it has not been boot-tested.
+The source is the `dsh-nu` GitHub release tarball, pinned by `hashes.json` in `nur-packages`;
+nix-config locks that package set in its `flake.lock`. `dsh.withPlugins` wraps the binary: each
+invocation gets a generated `--patch <file>` overlay after the profile layer, while `dsh plugin`
+stays untouched. No `$DSH_HOME/cordis.patch.yml` is written, so there is no home-layer state to
+resolve or roll back. Boundaries: preset rows that spawn a shell themselves (`custom-bash.mjs`,
+`persistent-shell`) bypass `ctx.shell`. So does `@deepseek-ai/dsh-experimental-terminal-bundle`: its
+`terminal_*` tools use a separate `ctx.terminals` seam and run the platform shell (bash on the POSIX
+hosts this repository manages), so they coexist with this plugin but stay outside the Nushell-only
+guarantee — keep the bundle off for a strict Nu-only machine. Bash hooks now run under Nushell and
+need rewriting; remote hosts still run their own POSIX shell. Rollback: install plain `dsh` or pass
+an empty plugin list; there is no home file to delete. Tested on Linux; the same package also builds
+for Darwin, where it has not been boot-tested.
 
 Verify after a switch:
 

home/base/tui/agents/packages.nix

@@ -16,7 +16,7 @@ in
     # dsh from nur-packages: llm-agents.nix's dsh cannot boot on nixpkgs node
     # (node-addon-require-builtin probe), this one shims it. The Nushell-only
     # plugin rides in through the package's withPlugins wrapper.
-    (myNurPkgs.dsh.withPlugins [ myNurPkgs.dsh-nushell-only ])
+    (myNurPkgs.dsh.withPlugins [ myNurPkgs.dsh-nu ])
 
     # Docs lookup CLI behind the find-docs skill (agents/skills/find-docs). The skill's flags are
     # written against this package, not against upstream's npx instructions.