nix-config-ryan4yin/home/base/tui/agents/dsh.md

dsh configuration

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
1	bundles	shipped with the profile	upstream
2	profile	$DSH_HOME/profiles/<name>/cordis.patch.yml	dsh, at runtime
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 nur-ryan4yin with dsh.withPlugins, which adds a --patch overlay after the profile layer.

Three behaviours that are easy to get wrong:

• A patch row's config replaces the row's config object instead of deep-merging into it. Repeat every key you mean to keep; the shipped agent-loop row repeats agents: [] for this reason.
• The web and desktop surfaces give each agent preset its own compaction service, so a top-level compaction-basic row never reaches a session. Compact by setting the route's model contextWindow and maxTokens instead.
• dsh-llm-pi-ai registers its providers once, so mount only one instance: a second one fails with provider "..." is already declared.

To see what your own patches actually change:

dsh <profile> --dump-config          # composed tree with every layer applied
dsh <profile> --dump-default-config  # the same tree without the home layer or --patch overlays

The dsh-base bundle sets agent-default-model to the API-key route (deepseek-official / deepseek-flash). The account route never falls back to an API key, so a host holding only DEEPSEEK_API_KEY fails new sessions with ACCOUNT_SIGN_IN_REQUIRED.

In this repository, just dsh-web boots the web profile through mihomo's mixed port.

Global rules

dsh-base already mounts dsh-agent-instructions (maxBytes: 65536) and rules.nix links agents/global-rules.md into both scopes it reads — $DSH_HOME/AGENTS.md and, from 0.2.1-alpha.2 on, $DSH_AGENTS_HOME/AGENTS.md — so no patch row is needed; identical content renders once.

• 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 is tested with Nushell 0.115.1 and warns at evaluation time when the resolved Nushell differs; drop the follows to build against its own pin instead. 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:

dsh --profile web --dump-config | grep -n "nu-executor\|nu-teaching"
# expect the first-party shell rows disabled, nu-executor and nu-teaching inserted
dsh --profile web o+e>| grep "disabling profile plugin"
# a dsh bump can disable a row whose manifest no longer matches; nothing prints when healthy