ai-regression-testing

ai-regression-testing is a skill for Claude Code, Codex from jxoesneon/Ciel. It costs 18 tokens per session (564 once invoked), scanned A, original, Apache-2.0.

A testing guide for software built with AI assistance. It focuses on checking that mock and production paths behave alike, API responses match their data queries, and errors leave the application in a correct state.

In plain words
What is it for?
Use it to design regression tests after bug fixes, verify response fields and error handling, and compare sandbox or mock behavior with production behavior.
Why use it?
It targets common AI coding mistakes, such as claiming a fix works, forgetting one execution path, or leaving old data after a failure.

Skill for Claude CodeCodex

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

Good fit Use it to design regression tests after bug fixes, verify response fields and error handling, and compare sandbox or mock behavior with production behavior.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jxoesneon/ciel/ai-regression-testing
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 jxoesneon/Ciel --skill ai-regression-testing
Clone the repo
git clone --depth 1 https://github.com/jxoesneon/Ciel

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 ai-regression-testing

README.md
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Your own site
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agentmods 80×15 button for ai-regression-testing

Your own site · 80×15
<a href="https://agentmods.dev/skills/jxoesneon/ciel/ai-regression-testing"><img src="https://agentmods.dev/badge/skills/jxoesneon/ciel/ai-regression-testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 564 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.
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 $0.00018 $0.00564
Opus 5 $0.00009 $0.00282
Sonnet 5 $0.00004 $0.00113
Haiku 4.5 $0.00002 $0.00056

Measured 9d ago against content hash eef65c0247c2, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

ai-regression-testing 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 9d 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.

skills/ai-regression-testing/SKILL.md · 72 lines

What it actually says

CIEL ADAPTATION: AI Regression Testing

This skill provides CIEL's specialized testing strategy for mitigating systematic blind spots in AI-assisted development. It focuses on contract-first verification and sandbox/production parity.

Integration Context

Adapted from ~/.agents/skills/ai-regression-testing/. This skill complements the core TDD mandate by targeting common AI failure patterns, such as "hallucinated success" and path inconsistency.

Core Patterns

1. Sandbox/Production Parity

Problem: AI fixes the production path but forgets the sandbox/mock path (or vice versa). Solution: Assert identical response shapes in both modes.

2. Contract Verification

Problem: AI adds a field to the response object but forgets to include it in the underlying data query (e.g., SELECT clause). Solution: Assert all required fields exist in the final API response.

3. Error/State Integrity

Problem: old data persists in the UI after an error, or optimistic updates lack proper rollback. Solution: Explicit tests for state cleanup and restoration on failure.

Orchestration Logic

1. Post-Fix Verification

After every bug fix (via systematic-debugging), CIEL must generate a specific regression test named after the bug (e.g., BUG-R1 regression).

2. Bug-Check Workflow

Run npm run test and npm run build before any AI-led code review to catch mechanical failures early.

3. Strategy: Test Where Bugs Cluster

Focus testing effort on auth, multi-path logic, and state management where AI regressions are most frequent. Do not aim for 100% coverage; aim for 100% regression prevention.


Original Documentation preserved at source.

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. 9d ago First seen · 72 lines · 18 tokens per session scan A eef65c0247c2

Subscribe to this mod's changes

ai-regression-testing is a skill published in the GitHub repository jxoesneon/Ciel (1 stars, last pushed 2d ago), licensed Apache-2.0. It adds 18 tokens to every session and 564 once invoked, about $0.0001 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 2026-08-31.

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