How do I install the Hydro Context skill?

Run npx skillmds@latest add tomevault-io/hydro-context in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Hydro Context safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Hydro Context?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Hydro Context free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Hydro Context?

tomevault-io (@tomevault-io) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Hydro Context by tomevault-io — Agent Skill

Name: Hydro Context
Author: tomevault-io

File contents

You are assisting with US hydrology / water resources engineering code. Apply the following domain knowledge automatically without asking the user to re-explain it.

Units

Discharge (streamflow): cubic feet per second (cfs) in US datasets; m³/s (cms) internationally
Stage (water level): feet in USGS data; metres in international datasets
Always check that input/output units are consistent; flag mismatches as a comment or warning

Key formulas

Rating curve (stage-discharge): Q = a × (H – H₀)^b

H = stage, H₀ = zero-flow stage offset, a and b are fitted constants
Typical b range: 1.5–3.0 for natural channels; fit in log-log space

Manning's equation (open-channel flow): Q = (1/n) × A × R^(2/3) × S^(1/2)

n = Manning's roughness (0.025–0.05 for natural channels)
R = hydraulic radius, S = channel slope (dimensionless, m/m or ft/ft)

Log-Pearson Type III is the standard US flood frequency distribution (USGS Bulletin 17C).

Work in log₁₀ space: fit the mean, standard deviation, and skewness of log₁₀(Q)

Weibull plotting position: P(X ≤ x) = m / (n + 1), return period T = (n + 1) / m

m = rank (1 = smallest), n = total number of data points

Flood frequency terminology

Return period (recurrence interval): average years between events of that magnitude or greater
Q2: 2-year flood (50% annual exceedance probability) ≈ bankfull flow in many streams
Q10: 10-year flood (10% AEP)
Q100: 100-year flood (1% AEP) — US regulatory floodplain standard
AEP: Annual Exceedance Probability = 1 / T

Data quality conventions

USGS missing-data sentinel: -999999 — always filter these before any calculation
Negative discharge values are physically impossible — treat as errors
Water year: Oct 1 – Sep 30 (US convention); water year N starts Oct 1 of year N-1
Minimum record length for reliable flood frequency: ≥ 10 years (30+ preferred for Q100)

Source: lorenliu13/claude-code-for-hydrology — distributed by TomeVault.

---name: hydro-contextdescription: Apply US hydrology domain knowledge — units, formulas, and conventions — when reading or writing hydrological code Use when this capability is needed.---You are assisting with US hydrology / water resources engineering code. Apply the following domain knowledge automatically without asking the user to re-explain it.## Units- Discharge (streamflow): cubic feet per second (cfs) in US datasets; m³/s (cms) internationally- Stage (water level): feet in USGS data; metres in international datasets- Always check that input/output units are consistent; flag mismatches as a comment or warning## Key formulas**Rating curve (stage-discharge):** `Q = a × (H – H₀)^b`- H = stage, H₀ = zero-flow stage offset, a and b are fitted constants- Typical b range: 1.5–3.0 for natural channels; fit in log-log space**Manning's equation (open-channel flow):** `Q = (1/n) × A × R^(2/3) × S^(1/2)`- n = Manning's roughness (0.025–0.05 for natural channels)- R = hydraulic radius, S = channel slope (dimensionless, m/m or ft/ft)**Log-Pearson Type III** is the standard US flood frequency distribution (USGS Bulletin 17C).- Work in log₁₀ space: fit the mean, standard deviation, and skewness of log₁₀(Q)**Weibull plotting position:** `P(X ≤ x) = m / (n + 1)`, return period `T = (n + 1) / m`- m = rank (1 = smallest), n = total number of data points## Flood frequency terminology- **Return period** (recurrence interval): average years between events of that magnitude or greater- **Q2**: 2-year flood (50% annual exceedance probability) ≈ bankfull flow in many streams- **Q10**: 10-year flood (10% AEP)- **Q100**: 100-year flood (1% AEP) — US regulatory floodplain standard- **AEP**: Annual Exceedance Probability = 1 / T## Data quality conventions- USGS missing-data sentinel: -999999 — always filter these before any calculation- Negative discharge values are physically impossible — treat as errors- **Water year**: Oct 1 – Sep 30 (US convention); water year N starts Oct 1 of year N-1- Minimum record length for reliable flood frequency: ≥ 10 years (30+ preferred for Q100)---> Source: [lorenliu13/claude-code-for-hydrology](https://github.com/lorenliu13/claude-code-for-hydrology) — distributed by [TomeVault](https://tomevault.io).

Frequently asked questions

Hydro Context