dsh-polyglot

The model switch for DSH. Point DeepSeek Harness at any OpenAI-compatible
endpoint — with curated presets for free and cheap DeepSeek providers and
automatic fallback when a free tier rate-limits you.

What claude-code-router is to Claude Code, dsh-polyglot is to DSH — except
DSH's ctx.llm is a sanctioned extension seam, so there is no request
interception: the generic adapter and the router are both real LlmAdapter
registrations.

• One generic adapter. A single OpenAI-compatible ctx.llm adapter
  parameterized by {baseUrl, apiKey, model, headers?, quirks?}. Streaming,
  tool calls, and usage extraction are all handled; per-provider deviations
  (reasoning field names, strict tool schemas, cache-folded usage) are small
  declarative quirks flags, never per-provider code.
• A router with fallback. On 429 / quota-exceeded / 5xx (or a missing
  key), the failing provider is marked cooling-down (exponential backoff,
  honoring Retry-After) and the request is retried on the next provider in
  the chain. Free tiers rate-limit constantly — automatic failover is the
  whole product.
• Provider presets as data. presets/*.json — community PRs add providers
  without touching the adapter. Each preset carries verifiedAt and free-tier
  notes so rot is visible.
• Usage you can see. Every attempt lands in the append-only session log as
  polyglot/served; /polyglot usage tallies per provider with token counts
  and estimated cost from preset pricing.

Quick start

Install the bundle into a profile (a DSH profile is an ordered stack of
plugin-bundle patch layers):

dsh plugin --profile web add @dsh-polyglot/bundle

The bundle's patch registers the polyglot plugin with the recommended
default chain — "code all day for free until something rate-limits, then
degrade gracefully to cheapest-paid":

nous-portal → opencode-zen → deepseek-official (5M grant) → kilo

Configure keys through the credentials seam (the web Models page writes them),
or export the env names each preset declares:

export NOUS_PORTAL_TOKEN=...      # nous-portal (bearer, manual token for v0.1)
export OPENCODE_API_KEY=...       # opencode-zen
export DEEPSEEK_API_KEY=...       # deepseek-official (new accounts: 5M free tokens, 30 days, no card)
export KILO_API_KEY=...           # kilo (paid fallback rung)

Pick the virtual provider polyglot in the model selector. A provider without
a configured key is skipped automatically — the chain degrades, it never
fails hard.

Day-to-day commands

Configuration

Override chains and cooldown from your profile patch:

# your profile's cordis.patch.yml (or --patch overlay)
- patch:
    - id: polyglot
      config:
        chains:
          default:
            - preset: nous-portal
            - preset: opencode-zen
            - preset: deepseek-official
              model: deepseek-v4-flash
            - preset: kilo
          paid:
            - preset: deepseek-official
              model: deepseek-v4-pro
        cooldown:
          baseMs: 30000        # initial per-provider cooldown after a failure
          maxMs: 900000        # ceiling (also honors provider Retry-After)
          factor: 2            # exponential growth per consecutive failure
          jitterRatio: 0.1     # symmetric jitter around each delay

Per-entry overrides: provider (route name), model, baseUrl, apiKeyEnv,
headers, quirks — the custom preset is the escape hatch for
vLLM/Ollama/SGLang localhost and any other OpenAI-compatible endpoint
(Qwen/GLM/Kimi official APIs included).

Quirks reference

Preset registry

All figures were re-verified 2026-08-14 against provider docs; these move
weekly — every preset carries verifiedAt, and a CI job pinging each
baseUrl with a 1-token request is the planned trust loop.

How it works

profile ──> provider route "polyglot" (the router meta-adapter)
              │  chain: nous-portal → opencode-zen → deepseek-official → kilo
              ▼
        ctx.llm.stream({provider: "nous-portal", ...})
              │  adapter per real route (OpenAiCompatAdapter, one per preset)
              ▼
        POST {baseUrl}/chat/completions   (SSE, usage, tools)

The router forwards the first attempt that completes. A fallback-eligible
failure that arrives before any content flowed — the free-tier ceiling
case — swaps to the next provider seamlessly; a failure after content flowed
cannot be unwritten and surfaces as a normal error finish. Which provider
actually served each turn is durable in the session log (polyglot/served),
so /polyglot usage is a pure fold over the log, not plugin-side accounting.

ToS note

Free tiers are often gated for evaluation use (OpenCode Zen's commercial
terms are undocumented). Preset notes surface this at configure time —
dsh-polyglot does not silently launder usage.

Development

pnpm install
pnpm typecheck    # strict TS
pnpm build        # tsc → lib/
pnpm test         # 56 tests: mock OpenAI-compat server with scripted 429/500/
                  # stream scenarios, golden wire assertions per quirk, and
                  # end-to-end cordis mounts proving fallback + session events

Roadmap

• v0.2 — per-role chains (planner → paid V4-Pro, executor/summarizer →
  free Flash); OAuth device flow for Nous Portal; preset auto-update check;
  provider benchmark/arena integration.
• Non-goals — proxying non-chat modalities; silent key laundering.