Model Switch
September 1, 2026 · View on GitHub
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Choose one explicit route for Main, Subagents, Web Search, image generation, the active conversation, and Plan execution in DeepSeek Harness. Model Switch uses public DSH services and provider-owned adapters; it does not patch DSH Core or manage provider credentials.

Routes
| Route | Behavior |
|---|---|
| Main model | Default provider, model, and optional effort for newly created sessions. Existing sessions are not migrated. |
| Subagent | Follow the active parent route, or use a fixed provider/model/effort. Workflow overrides remain authoritative. |
| Composer Picker | Changes only the active session and submits the exact catalog model id. Main defaults are preserved. |
| Plan Review | Chooses the execution model before the Plan approval response is sent. |
| Web Search | Keeps the official web_search tool and routes it through the selected Codex search adapter. |
| Image generation | Provides one stable generate_image tool routed through a selected Codex or Grok adapter. |
Invalid, unavailable, or unsupported routes fail explicitly. Model Switch never silently falls back to another provider or model.
Configure Main and Subagents
Open Settings → Model Switch. Main changes affect new sessions only. Subagents may follow Main or use a fixed provider, model, and effort.
Changing the Main or fixed Subagent provider/model replaces the previous model's effort with the target model's default. Models without reasoning support receive no effort.

Follow Main resolves the active parent request first, then the configured Main default. A fixed route is injected before the official Subagent descriptor is created. DSH 0.1.2-alpha.1 carries provider, model, and fixed reasoning effort in that descriptor.
How custom models appear in the Picker
Model Switch does not turn an arbitrary string in its own settings into a model. A provider plugin must publish the model to the official DSH model catalog first:
Provider configuration
→ provider publishes model rows to the DSH catalog
→ the active session Model Directory exposes provider/model metadata
→ Model Switch groups those catalog rows
→ the Picker submits the original provider id and model id
The catalog supplies the provider name, model id/name, reasoning efforts, and default effort. A saved route that is no longer present remains visible as unavailable in Settings; the Picker does not pretend it is routable.
Variant id grammar
Model Switch groups catalog rows by provider and by the model id after peeling these suffixes:
| Catalog model id | Picker variant |
|---|---|
acme-v1 | Standard row |
acme-v1-fast | Fast |
acme-v1-128k | Context 128K |
acme-v1-1m | Context 1M |
acme-v1-1m-fast | Context 1M + Fast |
Rules:
-fastcreates the Fast axis.-<n>kand-<n>mcreate Context tiers; suffixes may be combined with-fastin either order.reasoning.effortscreates the Effort choices;reasoning.defaultEffortselects the initial value.- Switching Fast, Context, or Thinking variants keeps the current effort only when the target catalog row supports it; otherwise the target row's default effort (or no effort) is used.
- Reasoning metadata marks a catalog row as Thinking-capable.
- Unrecognized ids remain independent model families; Model Switch never drops them.
To support a combined selection, the provider must publish the combined row. Publishing only acme-v1-fast and acme-v1-1m cannot represent Fast + 1M; publish acme-v1-1m-fast as well. The Picker never synthesizes a model id that the provider did not publish.
Plan Review
Plan Review owns an execution-model draft separate from Main. Confirm first commits that model to the active session, then answers the pending Plan review. A failed model commit leaves the review pending and retryable. Reject and Discuss in chat do not execute the Plan.

What Model Switch does not change
web_fetchand its configured provider- Vision routing,
read_image, and ordinary chat attachments - Provider login, credentials, or provider settings cards
- Official Agent Presets
- Existing provider-specific image tools
- Existing sessions when the Main default changes
Installation
Install Model Switch and only the provider adapters you use. These versions are validated with DSH 0.1.2-alpha.1:
DSH_HOME=~/.dsh dsh plugin --profile web add github:NOirBRight/dsh-llm-codex#v0.3.3
DSH_HOME=~/.dsh dsh plugin --profile web add github:NOirBRight/dsh-llm-grok#v0.3.3
DSH_HOME=~/.dsh dsh plugin --profile web add github:NOirBRight/dsh-model-switch#v0.4.2
For routed Web Search, set the existing Web plugin's searchProvider to model-switch and preserve its current fetchProvider. Model Switch never replaces web_fetch.
If dsh-composer-picker is installed, remove it from the profile before enabling Model Switch. Model Switch already owns the Composer Picker and Plan Review seat; two owners produce duplicate or competing UI.
Production profiles must use released GitHub tags rather than workspace-local dependencies. Restart the selected DSH profile after installation or route changes.
Compatibility
Model Switch targets DSH 0.1.2-alpha.1 through public Cordis/client services and plugin-owned adapters. No DSH Core patch is required.
Development
Requires Node 22.19+ and pnpm.
pnpm install
pnpm run check
check builds Host and Client artifacts, runs unit and Cordis/Settings composition tests, validates the extracted package, and verifies reproducible bundles. Product scope is defined in PRODUCT.md; implementation constraints live in IMPLEMENTATION_PLAN.md.
Release installation (Latest)
Explicit model routing for Main, Subagent, Composer, Plan Review, and capability tools. The release artifact targets DeepSeek Harness 0.1.2-alpha.1 and contains built Host/Client files only; it has no sibling-repository source, workstation path, or local protocol dependency.
Latest installation (the URL never contains a version):
dsh plugin --profile web add --force \
https://github.com/NOirBRight/dsh-model-switch/releases/latest/download/dsh-model-switch.tgz
Fixed-version installation:
dsh plugin --profile web add --force \
https://github.com/NOirBRight/dsh-model-switch/releases/download/v0.4.4/dsh-model-switch.tgz
Update, uninstall, and verify:
# Update to the latest Release
dsh plugin --profile web add --force \
https://github.com/NOirBRight/dsh-model-switch/releases/latest/download/dsh-model-switch.tgz
# Verify the loaded version
dsh plugin --profile web list
dsh plugin --profile web doctor
# Uninstall only this plugin
dsh plugin --profile web remove dsh-model-switch
Configuration: use the plugin section in Settings for Web UI plugins, or the profile dsh.profile.bundles entry for Host-only plugins. Start with this README's minimal YAML/JSON example and provide credentials/backend addresses explicitly.
Rollback: rerun the fixed v0.4.4 command, verify the profile list, then restart the Web service once. Inspect journalctl --user -u dsh-web.service and dsh plugin --profile web doctor; never put a source checkout in the production profile.
Release and integrity: v0.4.4 · SHA256SUMS.