chore(agents): drop the dsh-nu plugin

dsh-nu replaced every shell command with Nushell and refused bash/pwsh
syntax before it spawned; in practice the refusals were too noisy. Drop
the flake input, install plain dsh, and remove the docs describing the
Nushell-only shell.

Assisted-by: DeepSeek Harness (deepseek-flash)

agents/global-rules.md

@@ -119,9 +119,9 @@ For an impactful change, follow these steps in order, scaled to its risk:
   Agents MUST NOT delete config the task did not ask about; when config merely appears unused,
   report it instead. Ask before a breaking change.
 - Minimality is not a reason to encode a local workaround for an upstream defect. Fix the owning
-  upstream project first and consume the fixed revision; if a local stopgap is genuinely unavoidable,
+  upstream project first and consume the fixed revision; if a local stopgap is genuinely
-  stop and ask the user before adding it. "Minimal" means the smallest change that follows existing
+  unavoidable, stop and ask the user before adding it. "Minimal" means the smallest change that
-  best practice, not the smallest diff at any cost.
+  follows existing best practice, not the smallest diff at any cost.
 - Documentation should describe current behavior for readers without the conversation history; give
   each fact one home per audience and link instead of repeating. Comments explain contracts or
   non-obvious constraints, not obvious code, and preserve safety, license, and workaround
@@ -182,7 +182,7 @@ 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; dsh-nu fails closed rather than substituting another shell.
+- Use the shell the runtime provides; never hand work to another shell (`bash -c`, `sh -c`, `pwsh`).
   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.

flake.lock

@@ -145,27 +145,6 @@
         "type": "github"
       }
     },
-    "dsh-nu": {
-      "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ],
-        "nur-ryan4yin": "nur-ryan4yin"
-      },
-      "locked": {
-        "lastModified": 1793290908,
-        "narHash": "sha256-EXQpNeSoiLhk3NsfETZxuWbMwZT/01l/uP5maVziiCI=",
-        "owner": "ryan4yin",
-        "repo": "dsh-nu",
-        "rev": "b3a7c6eb7383aea56fe1ebbfbf06e5592952713a",
-        "type": "github"
-      },
-      "original": {
-        "owner": "ryan4yin",
-        "repo": "dsh-nu",
-        "type": "github"
-      }
-    },
     "fcitx5-vinput": {
       "inputs": {
         "nixpkgs": [
@@ -778,27 +757,6 @@
       }
     },
     "nur-ryan4yin": {
-      "inputs": {
-        "nixpkgs": [
-          "dsh-nu",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1793285532,
-        "narHash": "sha256-srlNGg3/PBb3DfaC9ROlYl68VjxJfKPJoddFSU89oOQ=",
-        "owner": "ryan4yin",
-        "repo": "nur-packages",
-        "rev": "4687255272d66973ee4a8c1b025ca9f84371b9a6",
-        "type": "github"
-      },
-      "original": {
-        "owner": "ryan4yin",
-        "repo": "nur-packages",
-        "type": "github"
-      }
-    },
-    "nur-ryan4yin_2": {
       "inputs": {
         "nixpkgs": [
           "nixpkgs"
@@ -899,7 +857,6 @@
         "catppuccin": "catppuccin",
         "colmena": "colmena",
         "disko": "disko",
-        "dsh-nu": "dsh-nu",
         "fcitx5-vinput": "fcitx5-vinput",
         "haumea": "haumea",
         "home-manager": "home-manager",
@@ -923,7 +880,7 @@
         "nixpkgs-patched": "nixpkgs-patched",
         "nixpkgs-stable": "nixpkgs-stable",
         "nu_scripts": "nu_scripts",
-        "nur-ryan4yin": "nur-ryan4yin_2",
+        "nur-ryan4yin": "nur-ryan4yin",
         "ponytail": "ponytail",
         "pre-commit-hooks": "pre-commit-hooks",
         "preservation": "preservation",

flake.nix

@@ -203,12 +203,5 @@
       url = "github:ryan4yin/nur-packages";
       inputs.nixpkgs.follows = "nixpkgs";
     };
-
-    # The Nushell-only shell bundle. Its flake builds the plugin from the
-    # repository, so a release needs only `nix flake update dsh-nu`.
-    dsh-nu = {
-      url = "github:ryan4yin/dsh-nu";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
   };
 }

home/base/tui/agents/README.md

@@ -15,9 +15,7 @@ Markdown with no Nix dependency; this module only wires it into place.
   [agents/skills/README.md](../../../../agents/skills/README.md).
 - `packages.nix`: agent CLIs (`codex`, `opencode`, `qwen-code`, `pi`) from the `llm-agents` flake
   input, dsh from `nur-ryan4yin`, `pkgs.ctx7` for the `find-docs` skill, and `pkgs.mcp-grafana` for
-  the Grafana MCP server. dsh's Nushell-only shell is selected when the package is built, via
+  the Grafana MCP server. Profile patches live in `~/.dsh/profiles/<name>/cordis.patch.yml`. See
-  `dsh.withPlugins` with the plugin from the `dsh-nu` flake input, so it is a derivation choice
-  rather than runtime state; profile patches live in `~/.dsh/profiles/<name>/cordis.patch.yml`. See
   [dsh.md](./dsh.md) for the layer order and the settings that bite.
 - `env.nix`: telemetry and auto-update opt-outs for the agents.
 

home/base/tui/agents/dsh.md

@@ -3,19 +3,18 @@
 dsh is installed by this module (`packages.nix`) and configured at runtime, not by Nix. It boots a
 profile: an ordered stack of patch layers over an empty root entry list, where later layers win.
 
-| #   | Layer     | Path                                         | Writer          |
+| #   | Layer   | Path                                         | Writer          |
-| --- | --------- | -------------------------------------------- | --------------- |
+| --- | ------- | -------------------------------------------- | --------------- |
-| 1   | bundles   | shipped with the profile                     | upstream        |
+| 1   | bundles | shipped with the profile                     | upstream        |
-| 2   | profile   | `$DSH_HOME/profiles/<name>/cordis.patch.yml` | dsh, at runtime |
+| 2   | profile | `$DSH_HOME/profiles/<name>/cordis.patch.yml` | dsh, at runtime |
-| 3   | home      | `$DSH_HOME/cordis.patch.yml`                 | you             |
+| 3   | home    | `$DSH_HOME/cordis.patch.yml`                 | you             |
-| 4   | `--patch` | whatever the launcher passes                 | package wrapper |
 
 `$DSH_HOME` defaults to `~/.dsh`. Settings UI changes are written to the profile patch; a home-layer
 row outranks it, so the UI rejects that setting with
 `Configuration for "..." is overridden by a home patch`. This repository ships no home layer:
 profile patches remain machine-local runtime state, the place for private endpoints (LAN servers,
-staging gateways) too. The shell swap is a package concern instead: Nix installs `dsh` from
+staging gateways) too. Nix installs plain `dsh` from `nur-ryan4yin`, with no package wrapper and no
-`nur-ryan4yin` with `dsh.withPlugins`, which adds a `--patch` overlay after the profile layer.
+`--patch` overlay.
 
 Three behaviours that are easy to get wrong:
 
@@ -50,42 +49,3 @@ on, `$DSH_AGENTS_HOME/AGENTS.md` — so no patch row is needed; identical conten
 - The scopes come from the environment: `0.2.1-alpha.2` removed the row's `dshHome` / `agentsHome`.
 - Nested `AGENTS.md` files are discovered by `read` / `write` / `edit`, not by `cd` inside `bash`,
   and nothing is watched: an external edit lands on the next such call, or on resume.
-
-## Nushell-only shell
-
-`dsh-nu`'s flake builds the bundle and `nur-ryan4yin`'s `dsh.withPlugins` applies it: every
-`ctx.shell` consumer (model shell tools, background jobs, hook bridges, in-process callers) runs
-`nu --no-config-file -c`, and a command that hands execution to another shell is refused before it
-spawns. The plugin adds Nushell rules and a syntax guide, and rewrites the shell-tool descriptions,
-so the model is told what actually runs. `nu` is the Nushell `dsh-nu`'s flake resolves — Nixpkgs',
-through `inputs.nixpkgs.follows` — substituted into the rendered patch at build time, so it does not
-depend on `PATH`. The bundle still records Nushell 0.115.1 as its tested release; nix-config follows
-the main nixpkgs and rewrites that manifest field to the resolved Nushell in `outputs/default.nix`
-until dsh-nu retests, rather than pinning an older nixpkgs for the whole plugin. A command that
-hands a script file to a shell (`bash scripts/build.sh`) is refused, and the refusal names the
-direct `./scripts/build.sh` spelling; the guard itself is unchanged.
-
-`home/base/tui/agents/packages.nix` calls `dsh-nu.lib.mkDshNuPackage { inherit pkgs dsh; }` and
-passes the result to `withPlugins`; `flake.lock` pins both inputs. `dsh.withPlugins` wraps the
-binary: each invocation gets a generated `--patch <file>` overlay after the profile layer, while
-`dsh plugin` stays untouched. No `$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:
-
-```sh
-dsh --profile web --dump-config | grep -nE 'nu-executor|nu-teaching'
-# expect the first-party shell rows disabled, nu-executor and nu-teaching inserted
-```
-
-A dsh bump can disable a row whose manifest no longer matches. That compatibility check runs only
-when a profile boots, not under the boot-free `--dump-config`, so read the stderr of the next boot
-(for example `just dsh-web`) for `disabling profile plugin`; nothing prints when healthy.

home/base/tui/agents/packages.nix

@@ -1,17 +1,10 @@
 {
   pkgs,
   llm-agents,
-  dsh-nu,
   ...
 }:
 let
   agentPackages = llm-agents.packages.${pkgs.stdenv.hostPlatform.system};
-  # dsh-nu's flake builds the plugin from its own checkout; this repository
-  # supplies the dsh installation it plugs into.
-  dshNu = dsh-nu.lib.mkDshNuPackage {
-    inherit pkgs;
-    inherit (pkgs) dsh;
-  };
   # llm-agents.nix still exposes OpenCode V2 as `opencode2` so it can coexist
   # with the v1 package. Re-expose its binary under the normal command name.
   opencode = pkgs.linkFarm "opencode" [
@@ -29,9 +22,8 @@ in
     agentPackages.qwen-code
     agentPackages.pi
     # 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
+    # (node-addon-require-builtin probe), this one shims it.
-    # plugin rides in through the package's withPlugins wrapper.
+    pkgs.dsh
-    (pkgs.dsh.withPlugins [ dshNu ])
 
     # 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.