rudder-transformations

rudder-transformations is a skill for Claude Code from rudderlabs/rudder-agent-skills. It costs 38 tokens per session (3,392 once invoked), scanned A, original, MIT.

A workflow for creating and managing RudderStack transformations, which change incoming data events before they are sent elsewhere. It uses the Rudder CLI and keeps transformation code, settings, reusable libraries, and test examples together.

In plain words
What is it for?
Use it to create or edit JavaScript or Python transformations and libraries, validate their YAML settings, run fixture-based tests, preview changes, and apply them.
Why use it?
It provides a repeatable way to check changes locally before applying them. This reduces the risk of deploying invalid transformations or output that differs from what was intended.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the rudder-cli plugin — 5 skills shipped together

Good fit Use it to create or edit JavaScript or Python transformations and libraries, validate their YAML settings, run fixture-based tests, preview changes, and apply them.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/rudderlabs/rudder-agent-skills/rudder-transformations
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 rudderlabs/rudder-agent-skills --skill rudder-transformations
Clone the repo
git clone --depth 1 https://github.com/rudderlabs/rudder-agent-skills

Made for: Claude Code.

Or install rudder-cli, the plugin that ships this one along with the rest of its 5 skills.

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 rudder-transformations

README.md
[![agentmods](https://agentmods.dev/badge/skills/rudderlabs/rudder-agent-skills/rudder-transformations/github.svg)](https://agentmods.dev/skills/rudderlabs/rudder-agent-skills/rudder-transformations)
Your own site
<a href="https://agentmods.dev/skills/rudderlabs/rudder-agent-skills/rudder-transformations"><img src="https://agentmods.dev/badge/skills/rudderlabs/rudder-agent-skills/rudder-transformations/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 rudder-transformations

Your own site · 80×15
<a href="https://agentmods.dev/skills/rudderlabs/rudder-agent-skills/rudder-transformations"><img src="https://agentmods.dev/badge/skills/rudderlabs/rudder-agent-skills/rudder-transformations.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 38 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,392 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 pass 7 Sept 2026
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 $0.00038 $0.03392
Opus 5 $0.00019 $0.01696
Sonnet 5 $0.00008 $0.00678
Haiku 4.5 $0.00004 $0.00339

Measured 12d ago against content hash 83606e1f3aad, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

rudder-transformations 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 12d ago.

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.

plugins/rudder-cli/skills/rudder-transformations/SKILL.md · 391 lines

How it starts

The opening of the file, as written. The whole thing — 391 lines — stays where its author put it; the contents beside it link to each section on GitHub.

RudderStack Transformations with Rudder CLI

Overview

RudderStack transformations allow real-time event manipulation using JavaScript or Python. Libraries provide reusable code shared across transformations. Both are managed as code using YAML specs and the Rudder CLI.

Follow this loop for every change — authoring a new transformation or library, or editing existing code. Testing locally with fixtures is the key step that distinguishes transformations work from other CLI workflows.

digraph transformations_workflow {
    rankdir=TB;
    "rudder-cli workspace info" [shape=box];
    "Authenticated?" [shape=diamond];
    "rudder-cli auth login" [shape=box];
    "Edit YAML / JS / fixtures" [shape=box];
    "rudder-cli validate -l ./" [shape=box];
    "Validation errors?" [shape=diamond];
    "Fix errors" [shape=box];
    "rudder-cli transformations test --all -l ./" [shape=box];
    "Tests pass?" [shape=diamond];
    "Fix code or expected output" [shape=box];
    "rudder-cli apply --dry-run -l ./" [shape=box];
    "Diff matches intent?" [shape=diamond];
    "Adjust specs" [shape=box];
    "rudder-cli apply -l ./" [shape=box];
    "Done" [shape=doublecircle];

    "rudder-cli workspace info" -> "Authenticated?";
    "Authenticated?" -> "rudder-cli auth login" [label="no"];
    "rudder-cli auth login" -> "rudder-cli workspace info";
    "Authenticated?" -> "Edit YAML / JS / fixtures" [label="yes"];
    "Edit YAML / JS / fixtures" -> "rudder-cli validate -l ./";
    "rudder-cli validate -l ./" -> "Validation errors?";
    "Validation errors?" -> "Fix errors" [label="yes"];
    "Fix errors" -> "rudder-cli validate -l ./";
    "Validation errors?" -> "rudder-cli transformations test --all -l ./" [label="no"];
    "rudder-cli transformations test --all -l ./" -> "Tests pass?";
    "Tests pass?" -> "Fix code or expected output" [label="no"];
    "Fix code or expected output" -> "rudder-cli validate -l ./";
    "Tests pass?" -> "rudder-cli apply --dry-run -l ./" [label="yes"];
    "rudder-cli apply --dry-run -l ./" -> "Diff matches intent?";
    "Diff matches intent?" -> "Adjust specs" [label="no"];
    "Adjust specs" -> "rudder-cli validate -l ./";
    "Diff matches intent?" -> "rudder-cli apply -l ./" [label="yes"];
    "rudder-cli apply -l ./" -> "Done";
}

Read the full file on GitHub · 391 lines

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. 12d ago First seen · 391 lines · 38 tokens per session scan A 83606e1f3aad

Subscribe to this mod's changes

rudder-transformations is a skill published in the GitHub repository rudderlabs/rudder-agent-skills (18 stars, last pushed 7d ago), licensed MIT. It adds 38 tokens to every session and 3,392 once invoked, about $0.0002 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 2026-08-30.

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