dsh-plugin-composer-cost

A DeepSeek Harness Web UI plugin that shows what a chat has cost and which DeepSeek rate window is active right now, in the row under the composer where the token statistics already live.

Click the pill for the breakdown:

The dot is amber during peak hours and green off-peak. The panel is the same trigger-anchored dialog the neighbouring statistic pills open, and it closes on an outside click or Escape.

What the amount covers

• The whole chat tree. A subagent runs as its own Session with its own durable usage, billed to the same account, so the pill sums the bound Session plus every subagent it spawned. The panel splits the two so the total stays explainable.
• Model turns only — the requests the provider reports usage for. See What it cannot include.

Peak schedule

Verified against https://api-docs.deepseek.com/quick_start/pricing on 2026-10-14.

Window (UTC)	Rate
Monday–Friday 01:00–04:00	peak
Monday–Friday 06:00–10:00	peak
every other instant, including the whole weekend	off-peak, exactly 50 % of peak

Chinese statutory public holidays are off-peak for the whole day. The official 2026 list (State Council notice 国办发明电〔2025〕7号) is built in. The 2027 notice lands in early November 2026 — add those dates to CN_HOLIDAYS, otherwise January 2027 is priced as an ordinary week.

DeepSeek ignores 调休 (make-up working days): an adjusted working Saturday is still a weekend and therefore off-peak.

Rates

Peak rates per 1,000,000 tokens, taken verbatim from the published rate cards. DeepSeek rounds CNY and USD independently, so neither is derived from the other:

Currency	Model	Cache hit	Cache miss	Output
CNY	deepseek-flash	0.04	2	8
CNY	deepseek-v4-pro	0.30	9	27
USD	deepseek-flash	0.006	0.30	1.20
USD	deepseek-v4-pro	0.044	1.32	3.96

Off-peak is half of each figure. DISPLAY_CURRENCY selects the card shown and is CNY by default. DeepSeek bills no separate cache-write rate, so cacheWriteTokens are listed but never charged. Unknown and legacy model ids fall back to the deepseek-flash row.

Install

Requires a DeepSeek Harness build with the Web GUI; the plugin renders into the conversation.composer.dock slot.

From the Plugins page. Sidebar → Plugins → Add plugin, paste https://github.com/nickkupriyanov/dsh-plugin-composer-cost, install, then reload the page.

From the CLI — forwards to pnpm in the profile directory:

dsh plugin --profile <profile> add https://github.com/nickkupriyanov/dsh-plugin-composer-cost

Side-loading a checkout, without pnpm: copy the checkout into the profile and add one loader row.

~/.dsh/profiles/<profile>/plugins/dsh-plugin-composer-cost/

# ~/.dsh/profiles/<profile>/cordis.patch.yml
- insert:
    - id: composer-cost
      name: ./plugins/dsh-plugin-composer-cost/index.js

Then fully restart the harness. The host caches client bundle bytes until a restart, and the browser module id is part of that cache key; a plain page refresh will not pick up a changed bundle.

Configuration

No runtime options — four constants at the top of client.js are the knobs.

Constant	Default	Meaning
DISPLAY_CURRENCY	'CNY'	'CNY' or 'USD', selects the rate card
RATE_ZONE	'Europe/Moscow'	zone every displayed wall-clock time is expressed in
RATE_CARDS	see above	the published rate cards, one per currency
CN_HOLIDAYS	2026 list	Chinese statutory holidays as YYYY-MM-DD

Accuracy

The durable tokenUsage projection carries whole-session totals with no per-request timestamps, so the cost is priced at the tariff in force at render time. A session that spans a peak boundary lands between the peak and off-peak figure; a session that never crosses one is exact.

Amounts print two decimals, and each part is rounded before summing so This chat + Subagents always equals the printed total. An amount that would round to zero prints <¥0.01 rather than claiming to be free.

What it cannot include

• Session titles and web search. Both are billed provider calls that the session log records as session/title-llm-request and web/deepseek-search-llm-request — requests only, with no usage attached, so no local computation can price them.
• Other clients on the same account. platform.deepseek.com/usage is account-wide; this pill is per chat.

Comparing with the billing console

Their totals differ for two structural reasons.

1. Scope. A pill is the lifetime of one chat tree, not a day. A chat that ran across midnight keeps its whole total.
2. The console day is Beijing time. Its day starts at 00:00 Beijing = 16:00 UTC of the previous day, so a session that ran at 00:01 Beijing belongs to "today" while a UTC-day total excludes it.

Measured on 2026-10-14 at 12:34 UTC by folding every session log on one machine and pricing at the off-peak CNY card:

Window	Total
UTC day, 2026-10-14 00:00Z to now	CNY 2.0752
Beijing day, 2026-10-13 16:00Z to now	CNY 2.2944
console reported	CNY 2.3300

The Beijing-day window lands within 1.5 % of the console; the residual is the helper calls above.

Files

File	Role
package.json	Bundle manifest: dsh.bundle.patch, the dsh.client web half, display metadata
cordis.patch.yml	Inserts the composer-cost loader row
index.js	Host half — intentionally empty
client.js	The pill, its panel, styles, dictionaries, and slot registration
locale/*.json	Plugin Manager card title and description
icon.svg	Plugin Manager artwork

No Harness Client package is imported: anchoring, outside-pointer dismissal, Escape handling and the coin glyph are implemented in client.js against --dsw-* design tokens only.

Development

No build step and no dependencies: client.js is the browser artifact in the loader lazy-factory form, checked in as source. Because nothing type-checks it before the Harness materializes it, scripts/check.cjs enforces the package contract instead - every exported entry point exists, the bundle patch names this package, the factory id equals the package name, and no Harness Client package is imported.

npm run check

CI runs the same checks on Node 20 and 22 for every push and pull request.

Changelog

Release notes live in CHANGELOG.md.

License

MIT