dsh-units 📐
Unit conversion toolbox for DeepSeek Harness (dsh) — 14 categories, zero runtime dependencies, pure arithmetic over a static unit table (no network, no filesystem, no code execution).
When your agent needs to answer "how many miles is 100 km?", "is 1 MB bigger than 1 MiB?", "what's 350°F in Celsius?", "how many tablespoons in 2 cups?", "16px is how many pt?" or "20 mpg in L/100km?" — instead of doing error-prone mental math, it can call these tools and read exact results.
> 中文简介：dsh-units 是 DeepSeek Harness 的单位换算工具箱插件，覆盖长度、质量、温度、面积、体积（含美制烹饪单位）、速度、时长、数据大小（十进制 MB 与二进制 MiB 严格区分）、压强、能量、角度、频率、排版印刷（px/pt/em/rem）、油耗（L/100km ↔ mpg ↔ km/L）共 14 个类别，零运行时依赖、纯算术实现，无网络无副作用。让 Agent 不再心算——特别是"MB/MiB 混淆""华氏摄氏互转""加仑换升""mpg 与 L/100km 互算"这类高频出错点，直接调用工具拿精确结果。
Why it exists
- LLMs are unreliable at unit math. Temperatures are affine (offset), data sizes mix decimal and binary prefixes, fuel economy is reciprocal (mpg vs. L/100km), and compound units (km/h, psi, kcal) hide awkward factors. A wrong conversion silently corrupts reports, recipes, travel plans, and capacity math.
- Fully deterministic and offline. Every factor lives in the static table in
src/units.ts— no API keys, no lookup services, nothing to drift. - Structured results. Each conversion returns the original value, both units (symbol + full name), the result, the formula applied, and the category — so the agent can explain its math instead of just asserting it.
Tools
| Tool | What it does |
|---|---|
convert_unit | Convert value from one unit to another within a category. Accepts symbols or full names (case-insensitive, °C, m², "miles", "MiB" all work). Rejects unknown units and cross-category pairs with clear errors. |
list_units | List all 14 categories with every unit symbol and full name (optionally one category, e.g. "data" or "temperature") — for discovering the exact symbols to pass to convert_unit. |
Supported categories
| Category | Units (symbols) |
|---|---|
| length | km, m, cm, mm, um, nm, in, ft, yd, mi, nmi |
| mass | t (metric tonne), kg, g, mg, lb, oz |
| temperature | c, f, k — affine conversion with offsets |
| area | km2, ha, m2, cm2, mm2, mi2, acre, yd2, ft2, in2 |
| volume (incl. cooking) | m3, l, ml, cm3, gal, qt, pint, cup, floz, tbsp, tsp (US units) |
| speed | km/h, m/s, mph, knot, ft/s |
| time duration | yr (Julian, 365.25 d), wk, d, h, min, s, ms |
| data size / transfer | tbit…bit, pb…b (decimal), pib…kib (binary) — MB ≠ MiB |
| pressure | mpa, kpa, bar, atm, psi, mmhg, torr, pa |
| energy | kwh, wh, kcal, kj, cal, j, ev |
| angle | deg, rad, grad |
| frequency / rotation | ghz, mhz, khz, hz, rpm |
| typography (CSS / print) | px, pt, pc (pica), em, rem — 96 dpi reference, 16 px base font for em/rem |
| fuel economy | l/100km, l/km, mpg (US), mpg(uk) (imperial), km/l — reciprocal, mpg ≠ linear |
> v0.2.0 note: pt now means the typography point (previously the US pint). Use pint for pints — convert_unit { value: 1, from: "pint", to: "l" } still works. em/rem assume the common 16 px browser default base font size; px assumes 96 dpi (documented assumptions, not physical absolutes).
Install
dsh plugin --profile default add github:TYEclipse/dsh-unitsor clone and build locally:
git clone https://github.com/TYEclipse/dsh-units.git
cd dsh-units && pnpm install && pnpm buildUsage
The agent just calls the tools — no setup beyond installation:
convert_unit { value: 100, from: "km", to: "mi" }
→ 100 km = 62.137119 mi (length, × 0.621371)
convert_unit { value: 500, from: "MiB", to: "MB" }
→ 500 MiB = 524.288 MB (data size / transfer, × 1.048576)
convert_unit { value: 350, from: "fahrenheit", to: "celsius" }
→ 350 f = 176.666667 c (temperature, (x − 32) × 5/9)
convert_unit { value: 16, from: "px", to: "pt" }
→ 16 px = 12 pt (typography (CSS / print), × 0.75)
convert_unit { value: 20, from: "mpg", to: "l/100km" }
→ 20 mpg = 11.760729 l/100km (fuel economy, 235.214583 ÷ x → x)
list_units { category: "volume" }
→ volume (volume (incl. cooking), base: liter): m3 = cubic meter | l = liter | ...Configuration
plugins:
dsh-units:
maxDecimals: 6 # display rounding: decimals ≥ 1, significant digits below (1–12)Safety model
- Pure math. No network, no filesystem access, no subprocesses, no code execution.
- Strict input validation. Unknown units, cross-category pairs, and non-finite values throw descriptive errors instead of returning garbage.
- Display-only rounding. Internal computation keeps full float precision; rounding applies to the returned
resultonly. - No opinions about validity. Converting
-10 Kreturns the arithmetic result; physical plausibility is the caller's business (documented so agents don't over-trust the tool).
Development
pnpm install
pnpm build # tsc, strict
pnpm test # vitest, fully offline fixtures
pnpm lint # oxlint (src + test only)License
MIT © 2026 TYEclipse