sc-ambient-removal

sc-ambient-removal is a skill for Claude Code, Codex from TianGzlab/OmicsClaw. It costs 59 tokens per session (1,399 once invoked), scanned A, original, Apache-2.0.

A single-cell data-cleaning step that reduces ambient RNA contamination in droplet experiments. Ambient RNA is genetic material released by broken cells that can be mistakenly counted in nearby droplets.

In plain words
What is it for?
Use it with raw or filtered droplet-based single-cell counts, such as 10x data, when free-floating RNA is suspected. It does not detect doublets, which are droplets containing multiple cells.
Why use it?
Contamination can make a cell appear to express genes that do not belong to it, which can distort later analysis. This removes or reduces those unwanted signals before downstream work.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it with raw or filtered droplet-based single-cell counts, such as 10x data, when free-floating RNA is suspected. It does not detect doublets, which are droplets containing multiple cells.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/tiangzlab/omicsclaw/sc-ambient-removal
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add TianGzlab/OmicsClaw --skill sc-ambient-removal
Clone the repo
git clone --depth 1 https://github.com/TianGzlab/OmicsClaw

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for sc-ambient-removal

README.md
[![agentmods](https://agentmods.dev/badge/skills/tiangzlab/omicsclaw/sc-ambient-removal/github.svg)](https://agentmods.dev/skills/tiangzlab/omicsclaw/sc-ambient-removal)
Your own site
<a href="https://agentmods.dev/skills/tiangzlab/omicsclaw/sc-ambient-removal"><img src="https://agentmods.dev/badge/skills/tiangzlab/omicsclaw/sc-ambient-removal/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for sc-ambient-removal

Your own site · 80×15
<a href="https://agentmods.dev/skills/tiangzlab/omicsclaw/sc-ambient-removal"><img src="https://agentmods.dev/badge/skills/tiangzlab/omicsclaw/sc-ambient-removal.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 59 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,399 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Rogue Agent · line 3
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00059 $0.01399
Opus 5 $0.00030 $0.00700
Sonnet 5 $0.00012 $0.00280
Haiku 4.5 $0.00006 $0.00140

Measured 6d ago against content hash 6a10c804524e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

sc-ambient-removal scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (sc_ambient.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/singlecell/scrna/sc-ambient-removal/SKILL.md · 117 lines

How it starts

The opening of the file, as written. The whole thing — 117 lines — stays where its author put it; the contents beside it link to each section on GitHub.

sc-ambient-removal

When to use

The user has filtered (or raw + filtered) droplet-based scRNA-seq counts and suspects ambient RNA from cell-free droplets is inflating per-cell expression — typical for 10X data with high droplet density. Three backends share the CLI: simple (a deterministic ambient-profile subtraction, default), cellbender (Python, requires GPU for sensible runtime), and soupx (R via rpy2; needs raw + filtered matrices). Doublets are a different problem — use sc-doublet-detection for multiplet barcodes.

Inputs & Outputs

Inputs

  • Input kinds: file, directory
  • Modalities: scrna
  • File types: .h5ad, .h5, .loom, .csv, .tsv

Outputs

  • tables/cell_metadata.csv
  • tables/cellbender_output_cell_barcodes.csv
  • tables/cellbender_output_metrics.csv
  • tables/cells.csv
  • tables/corrected_counts.csv
  • tables/correction_summary.csv
  • tables/gene_expression.csv
  • tables/genes.csv
  • figures/barcode_rank.png
  • figures/count_distribution.png
  • figures/counts_comparison.png
  • figures/r_ambient_violin.png
  • README.md
  • analysis_summary.txt
  • cellbender_output_report.html
  • contamination.json
  • processed.h5ad
  • report.md
  • result.json
  • Processed AnnData (saves_h5ad) — adds layers: counts; uns: ambient_correction, soupx, cellbender

Flow

  1. Load filtered AnnData; optionally load raw matrix (SoupX requires both).
  2. Validate --contamination is in [0, 1) and --expected-cells is positive when set.
  3. Run the chosen --method against METHOD_REGISTRY.
  4. If the requested backend is unavailable, fall back deterministically to simple.
  5. Stash the pre-correction matrix in layers["counts"] and overwrite adata.X with the corrected counts; record the run params in uns["ambient_correction"|"soupx"|"cellbender"].
  6. Render diagnostic figures + emit report.md + result.json.

Read the full file on GitHub · 117 lines

Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 117 lines · 59 tokens per session scan A 6a10c804524e

Subscribe to this mod's changes

sc-ambient-removal is a skill published in the GitHub repository TianGzlab/OmicsClaw (160 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 59 tokens to every session and 1,399 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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