Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/PramodDutta/qaskillsnpx agentmods add skills/pramoddutta/qaskills/docker-testcontainersWrote 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.
[](https://agentmods.dev/skills/pramoddutta/qaskills/docker-testcontainers)<a href="https://agentmods.dev/skills/pramoddutta/qaskills/docker-testcontainers"><img src="https://agentmods.dev/badge/skills/pramoddutta/qaskills/docker-testcontainers/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.
<a href="https://agentmods.dev/skills/pramoddutta/qaskills/docker-testcontainers"><img src="https://agentmods.dev/badge/skills/pramoddutta/qaskills/docker-testcontainers.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, 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 Memory Poisoning · line 24 Skill manipulates agent memory, state, or stored context. Memory corruption can alter personality, override safety rules, or cause unpredictable behavior.Fix: Protect agent memory and state from modification by untrusted content. Use read-only memory for critical instructions and validate all state changes.
- medium Rogue Agent · line 17 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00042 | $0.02356 |
| Opus 5.5 | $0.00017 | $0.00942 |
| Sonnet 5.5 | $0.00008 | $0.00471 |
| Haiku 4.5 | $0.00004 | $0.00236 |
Grade A, and why
Docker Testcontainers 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 221 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Docker Testcontainers
This skill makes an AI agent write integration tests that spin up real databases, caches, and message brokers in disposable Docker containers via the testcontainers Node.js library - instead of mocking them or depending on a shared dev server. Trigger it when tests need a real Postgres, Redis, Kafka, or any service with Docker image, when a repo already imports testcontainers, or when the user complains that mocked repositories keep hiding SQL and serialization bugs.
Core Principles
- Test against the real engine, not a lookalike. SQLite in place of Postgres misses JSONB operators, transaction isolation behavior, and case-sensitivity rules. Run the exact image and major version production uses (
postgres:16-alpine, notlatest). - Always use mapped ports. Containers bind to random free host ports. Read them with
container.getMappedPort(5432)andcontainer.getHost(); hardcodinglocalhost:5432collides with local services and parallel CI jobs. - Wait strategies, not sleeps. A started container is not a ready service. Use
Wait.forLogMessage,Wait.forListeningPorts,Wait.forHttp, orWait.forHealthCheckso tests begin exactly when the dependency is usable. - One container per suite, clean state per test. Container startup costs seconds; start in
beforeAll, then reset state between tests withTRUNCATE,FLUSHALL, or transaction rollbacks - not by restarting the container. - Cleanup must survive failures. Stop containers in
afterAll; Testcontainers' Ryuk sidecar reaps anything left behind if the process dies, so never disable it in CI. - Pin image tags.
redis:latestchanging under you turns a green suite red with zero code changes. Pin to a major-minor tag and upgrade deliberately.
Setup
npm install --save-dev testcontainers @testcontainers/postgresql
# Requires a running Docker daemon (Docker Desktop, Colima, or CI's dockerd)
docker info
Patterns
1. GenericContainer: Redis with a wait strategy
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.
- 1mo ago First seen · 221 lines · 42 tokens per session scan A 9be2c71f1054
Docker Testcontainers is a skill published in the GitHub repository PramodDutta/qaskills (237 stars, last pushed 8d ago), licensed MIT. It adds 42 tokens to every session and 2,356 once invoked, about $0.0002 per session on Opus 5.5. 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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