refactor(agents): link dsh shared policy as a home-layer patch (#388)

dsh rewrites a profile's cordis.patch.yml at runtime, so linking the web
profile put GUI state in the checkout and let runtime writes clobber manual
edits. Link the stable policy as the $DSH_HOME home layer instead: dsh applies
it after every profile and only reads it.

The host-plane compaction-basic row is disabled on the web surface and each
agent preset owns its own copy, so the top-level override was inert. Drop it;
the model contextWindow/maxTokens are the effective knobs.

- add home/base/tui/agents/dsh/cordis.patch.yml, linked from default.nix
- drop the ~/.dsh/profiles/web link and the tracked web/ profile
- keep runtime state and private/local model routes in the profile patch
- update the eval test and README

home/base/tui/agents/README.md

@@ -13,8 +13,8 @@ Nix dependency; this module only wires it into place.
 - `packages.nix`: agent CLIs (`codex`, `opencode2`, `pi`) from the `llm-agents` flake input, plus
   `pkgs.mcp-grafana` for the Grafana MCP server.
 - `env.nix`: telemetry and auto-update opt-outs for the agents.
-- `dsh/`: the dsh `web` profile that lives in `~/.dsh`. See [dsh/README.md](./dsh/README.md) for the
-  link granularity, the tracked members and which hosts import it.
+- `dsh/`: the shared dsh home-layer patch linked to `~/.dsh/cordis.patch.yml`. See
+  [dsh/README.md](./dsh/README.md) for why the shared layer is linked and the profile patch is not.
 
 ## Deployed rule targets
 

home/base/tui/agents/dsh/README.md

@@ -1,26 +1,21 @@
 # dsh
 
-The dsh (DeepSeek Harness) `web` profile, linked into `~/.dsh/profiles/web` from the checked-in
-files under [`web/`](./web).
+Shared dsh (DeepSeek Harness) policy, linked into `~/.dsh/cordis.patch.yml`.
 
-## Why the link targets the directory
+## Layers
 
-dsh persists Settings through `cordis.patch.yml` with an atomic write (a random-suffix sibling, then
-a rename), and that rename replaces a symlinked target instead of writing through to its referent. A
-file-level link — store or out-of-store — is destroyed by the first Settings save, while a directory
-link keeps the write inside the checkout. Same reasoning as `home/base/tui/tuios`, one level up.
+dsh composes a profile from bundle patches, the profile's own `cordis.patch.yml`, then
+`$DSH_HOME/cordis.patch.yml` (the "home" layer) and `--patch` overlays. The home layer is the only
+one shared by every profile and surface, so the stable policy lives here.
 
-| Profile member        | Tracked | Role                                       |
-| --------------------- | ------- | ------------------------------------------ |
-| `cordis.patch.yml`    | yes     | the user patch layer the Settings UI edits |
-| `package.json`        | yes     | the profile's `dsh.profile.bundles` list   |
-| `pnpm-workspace.yaml` | yes     | the profile's pnpm settings                |
-| `cordis.yml`          | no      | rewritten on every boot                    |
-| `node_modules/`       | no      | written by `dsh plugin --profile web ...`  |
+| Layer   | Path                                      | Writer                        | Tracked |
+| ------- | ----------------------------------------- | ----------------------------- | ------- |
+| home    | `~/.dsh/cordis.patch.yml`                 | nix-config; dsh only reads it | yes     |
+| profile | `~/.dsh/profiles/<name>/cordis.patch.yml` | dsh, at runtime               | no      |
 
-`web/.gitignore` owns the untracked rows. As with the rules links in the parent module, the
-trade-off is a config that stays writable in the checkout: a Settings change and a commit are the
-same edit, and the configuration is shared by every host that deploys the profile.
+dsh writes the profile patch but only reads the home layer, so linking the home layer is safe while
+linking the profile patch would put runtime state in the checkout. Declared settings are edited
+here, not in the Settings UI.
 
 ## Which hosts deploy it
 
@@ -31,11 +26,34 @@ host that ships dsh needs one of those two wirings.
 
 ## Default model route
 
-`web/cordis.patch.yml` pins `agent-default-model` to the API-key route (`deepseek-official`). The
+`cordis.patch.yml` pins `agent-default-model` to the API-key route (`deepseek-official`). The
 account route (`deepseek-account`) never falls back to an API key, so a host holding only
 `DEEPSEEK_API_KEY` fails every freshly created session with `ACCOUNT_SIGN_IN_REQUIRED`. A host that
-signs in instead can select an account model per session, or override the field in its own
-`$DSH_HOME/cordis.patch.yml`, which the home layer applies last and which therefore wins.
+signs in instead can select an account model per session.
+
+## Compaction
+
+The web and desktop surfaces give each agent preset its own compaction service, so a top-level
+`compaction-basic` row here never reaches a session. The effective knobs are the model
+`contextWindow` and `maxTokens`: the `400000`/`32000` values set here place the first compaction
+near 300k tokens.
+
+## Private and local model routes
+
+Endpoints that must not enter this repository — LAN/self-hosted servers and staging gateways — do
+not belong in the home layer. Declare them locally as a separate pi-ai instance in the profile
+patch, which dsh does not deploy from here:
+
+```yaml
+# ~/.dsh/profiles/<name>/cordis.patch.yml
+- insert:
+    - id: llm-pi-ai-private
+      name: "@deepseek-ai/dsh-llm-pi-ai"
+      config:
+        providers: { ... }
+```
+
+The private instance coexists with the shared one under its own id.
 
 ## Running it
 

home/base/tui/agents/dsh/cordis.patch.yml

@@ -0,0 +1,70 @@
+# Shared dsh policy. Linked to ~/.dsh/cordis.patch.yml and applied as the
+# $DSH_HOME ("home") layer, after each profile's own patch, so it covers every
+# profile and surface. dsh only reads it — keep runtime preferences and local
+# model routes in the profile patch (see README.md).
+- id: agent-default-model
+  name: "@deepseek-ai/dsh-agent-default-model"
+  config:
+    provider: deepseek-official
+    model: deepseek-flash
+    reasoningEffort: high
+- id: locale
+  name: "@deepseek-ai/dsh-client-locale"
+  config:
+    preference: zh
+- id: agent-preset-registry
+  name: "@deepseek-ai/dsh-agent-preset-registry"
+  config:
+    default: standard
+    selectedDefault: ptc
+- id: llm-deepseek
+  name: "@deepseek-ai/dsh-llm-deepseek-api-key"
+  config:
+    models:
+      - id: deepseek-flash
+        name: DeepSeek-V41-Flash
+        inputModalities:
+          - text
+          - image
+        systemPromptUpdate: in-history
+        toolUpdate: addition-only
+        contextWindow: 400000
+        maxTokens: 32000
+      - id: deepseek-v4-pro
+        name: DeepSeek-V4-Pro
+        description:
+          Stronger agentic coding, knowledge, and difficult reasoning; suited to complex or
+          quality-critical tasks at higher cost.
+        contextWindow: 500000
+        inputModalities:
+          - text
+- id: llm-deepseek-account
+  name: "@deepseek-ai/dsh-llm-deepseek-account"
+  config:
+    models:
+      - id: deepseek-flash
+        name: DeepSeek-V41-Flash
+        inputModalities:
+          - text
+          - image
+        systemPromptUpdate: in-history
+        toolUpdate: addition-only
+        contextWindow: 400000
+        maxTokens: 32000
+      - id: deepseek-v4-pro
+        name: DeepSeek-V4-Pro
+        description:
+          Stronger agentic coding, knowledge, and difficult reasoning; suited to complex or
+          quality-critical tasks at higher cost.
+        contextWindow: 500000
+        inputModalities:
+          - text
+- id: agent-loop
+  name: "@deepseek-ai/dsh-agent-loop"
+  config:
+    agents: []
+    maxParallelToolCalls: 8
+- id: subagent
+  name: "@deepseek-ai/dsh-subagent"
+  config:
+    maxActiveSubagents: 3

home/base/tui/agents/dsh/default.nix

@@ -3,19 +3,10 @@
   ...
 }:
 let
-  # dsh persists Settings through the profile's cordis.patch.yml with an atomic
-  # write (a random-suffix sibling, then a rename), and that rename replaces a
-  # symlinked target instead of writing through to its referent. A file-level
-  # link, store or out-of-store, therefore survives only until the first save.
-  # Linking the whole profile directory keeps the write inside the checkout and
-  # leaves the directory symlink intact. Same reasoning as
-  # `home/base/tui/tuios`, one level up; the checkout path is hardcoded like the
-  # repo's other out-of-store links.
-  profileDir = "${config.home.homeDirectory}/nix-config/home/base/tui/agents/dsh/web";
+  # Out-of-store so repo edits apply without a rebuild (see README.md).
+  sharedPatch = "${config.home.homeDirectory}/nix-config/home/base/tui/agents/dsh/cordis.patch.yml";
 in
 {
-  # The `web` profile's configuration, owned by hand and by the Settings UI.
-  # Generated members of the profile (cordis.yml, node_modules, lock files) are
-  # gitignored inside that directory rather than tracked.
-  home.file.".dsh/profiles/web".source = config.lib.file.mkOutOfStoreSymlink profileDir;
+  # The shared dsh policy, read as $DSH_HOME/cordis.patch.yml.
+  home.file.".dsh/cordis.patch.yml".source = config.lib.file.mkOutOfStoreSymlink sharedPatch;
 }

home/base/tui/agents/dsh/web/.gitignore

@@ -1,10 +0,0 @@
-# Regenerated by dsh on every boot (always the empty root entry list).
-cordis.yml
-
-# Written by `dsh plugin --profile web ...`.
-node_modules/
-pnpm-lock.yaml
-
-# Transient siblings of the atomic-write and file-lock protocols.
-*.tmp
-*.lock

home/base/tui/agents/dsh/web/cordis.patch.yml

@@ -1,77 +0,0 @@
-# Your patch layer for this dsh profile, applied after every bundle layer:
-# a top-level YAML array of loader patch entries (id-targeted config
-# overrides, disables, and insert lists; `!!js` expressions allowed).
-- id: ui-settings-general
-  name: "@deepseek-ai/dsh-client-ui-settings-general"
-  config:
-    welcomeNoticeVersion: 2026-09-28.1
-- id: agent-default-model
-  name: "@deepseek-ai/dsh-agent-default-model"
-  config:
-    provider: deepseek-official
-    model: deepseek-flash
-    reasoningEffort: high
-- id: ui-settings-account
-  name: "@deepseek-ai/dsh-client-ui-settings-account"
-  config:
-    version: 1
-    step: done
-    purpose: development
-    process: standard
-    completion: completed
-    usage: detailed
-    developerTools: true
-- id: ui-chat
-  name: "@deepseek-ai/dsh-client-ui-chat"
-  config:
-    transcriptView: standard
-    performanceUsage: detailed
-- id: ui-settings
-  name: "@deepseek-ai/dsh-client-ui-settings"
-  config:
-    enabled: true
-- id: locale
-  name: "@deepseek-ai/dsh-client-locale"
-  config:
-    preference: zh
-- id: agent-preset-registry
-  name: "@deepseek-ai/dsh-agent-preset-registry"
-  config:
-    default: standard
-    selectedDefault: ptc
-- id: llm-deepseek-account
-  name: "@deepseek-ai/dsh-llm-deepseek-account"
-  config:
-    models:
-      - id: deepseek-flash
-        name: DeepSeek-V41-Flash
-        inputModalities:
-          - text
-          - image
-        systemPromptUpdate: in-history
-        toolUpdate: addition-only
-        contextWindow: 1000000
-      - id: deepseek-v4-pro
-        name: DeepSeek-V4-Pro
-        description: Stronger agentic coding, knowledge, and difficult reasoning; suited to complex or quality-critical tasks at higher cost.
-        contextWindow: 500000
-        inputModalities:
-          - text
-- id: agent-loop
-  name: "@deepseek-ai/dsh-agent-loop"
-  config:
-    agents: []
-    maxParallelToolCalls: 8
-- id: subagent
-  name: "@deepseek-ai/dsh-subagent"
-  config:
-    maxActiveSubagents: 3
-- id: compaction-basic
-  name: "@deepseek-ai/dsh-compaction-basic"
-  config:
-    thresholdRatio: 0.35
-    retainRatio: 0.16
-    headroomTokens: 65536
-    compactionRetries: 1
-    maxOverflowRetries: 1
-    auto: true

home/base/tui/agents/dsh/web/package.json

@@ -1,14 +0,0 @@
-{
-  "name": "dsh-profile-web",
-  "private": true,
-  "dependencies": {},
-  "dsh": {
-    "profile": {
-      "bundles": [
-        "@deepseek-ai/dsh-base",
-        "@deepseek-ai/dsh-web-app",
-        "@deepseek-ai/dsh-experimental-auto-review"
-      ]
-    }
-  }
-}

home/base/tui/agents/dsh/web/pnpm-workspace.yaml

@@ -1,5 +0,0 @@
-packages:
-  - .
-
-nodeLinker: hoisted
-autoInstallPeers: false