dsh-ark-plan

Activate DeepSeek v4 flash on the Volcano Ark plan API (https://ark.cn-beijing.volces.com/api/plan/v3) in DeepSeek Harness — the budget lane: 10× cheaper off-peak token bundles for the same model.

Strategy: built-in route + baseURL override (no custom provider)

The plugin reuses pi-ai's built-in deepseek provider — which already knows the models (reasoning incl. effort=max, 1M context, 384K output) — and only overrides baseURL to point at Ark's plan API. No hand-rolled "ark" provider, nothing to re-declare, nothing to silently degrade.

Two lanes coexist:

Lane	Provider	baseURL	Key env	Key prefix
Official (default)	deepseek-official	api.deepseek.com	DEEPSEEK_API_KEY	sk-...
Ark budget	deepseek (DeepSeek V4 Flash(ARK))	ark plan API	ARK_API_KEY	ark-...

Default model stays on the official route; the ark lane is there to burn the cheap plan tokens when you want them — switch the model picker to the deepseek provider's models to use it, then switch back when the bundle runs out (don't buy more: the plan's value ends there).

Install

dsh plugin --profile web add github:snow-The/dsh-ark-plan
# restart dsh web

Configure keys

# ~/.dsh/.credentials.yaml (or the Models page)
DEEPSEEK_API_KEY: sk-...      # official DeepSeek key (official lane)
ARK_API_KEY: ark-...          # Volcano Ark plan key (ark lane)

The two envs are deliberately separate — a sk- key against the ark baseURL answers 401 AuthenticationError and vice versa.

Verify

Ask your agent to run ark_plan_doctor. It reads the current config, flags the known mistakes, and live-tests ark /chat/completions with the deepseek thinking format (thinking.type=enabled + reasoning_effort=max) — expect serverModel = deepseek-v4-flash-ga-<date> (e.g. ...-ga-260731, the 0731 build) and thinking: true.

Traps this plugin encodes

Trap	Symptom if missed
Stale standalone ark provider (v0.1 layout)	A duplicate "ark | 自定义" entry in the Models page with a red dot. Remove llm-pi-ai.providers.ark.
reasoningEffort: max not set	Thinking runs at the endpoint default (high), not max.
Wrong key family for the baseURL	sk-... against ark → 401; ark-... against api.deepseek.com → 401. Match key to endpoint.
ARK_API_KEY missing	The ark lane exists but answers 401 until its key is filled.
baseURL not the ark plan API	Plugin defaults do nothing if deepseek.baseURL points at api.deepseek.com — that's just the official route.

How the defaults work

dsh-settings registers each entry's patch config as the base of its settings section, so plugin defaults only apply where the user has not configured the same keys. No overwriting of user settings.

License

MIT