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.
npx skills add cwinvestments/memstack --skill test-writergit clone --depth 1 https://github.com/cwinvestments/memstackWrote 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/cwinvestments/memstack/test-writer)<a href="https://agentmods.dev/skills/cwinvestments/memstack/test-writer"><img src="https://agentmods.dev/badge/skills/cwinvestments/memstack/test-writer/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/cwinvestments/memstack/test-writer"><img src="https://agentmods.dev/badge/skills/cwinvestments/memstack/test-writer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 5 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 142 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.
- high Memory Poisoning · line 197 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 MCP Rug Pull · line 375 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 411 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 413 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00070 | $0.03745 |
| Opus 5.5 | $0.00028 | $0.01498 |
| Sonnet 5.5 | $0.00014 | $0.00749 |
| Haiku 4.5 | $0.00007 | $0.00375 |
Grade A, and why
memstack-development-test-writer 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 — 473 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Writer: Generating test suite...
Generates comprehensive test suites with unit, integration, and e2e tests, proper mocking strategies, edge case coverage, naming conventions, and CI integration patterns.
Activation
When this skill activates, output:
Test Writer: Generating test suite...
Then execute the protocol below.
Context Guard
| Context | Status |
|---|---|
| User says "write tests", "add tests", "test coverage" | ACTIVE |
| User says "unit tests", "integration tests", "component tests", "e2e tests" | ACTIVE |
| User says "mocking", "edge cases", "test this function" | ACTIVE |
| User wants to refactor existing code | DORMANT: use Refactor Planner |
| User wants to change database schema | DORMANT: use Migration Planner |
Common Mistakes
| Mistake | Why It's Wrong |
|---|---|
| "Testing implementation, not behavior" | Tests that break when you refactor internals are brittle. Test WHAT it does, not HOW. |
| "No edge cases" | Happy path tests catch 20% of bugs. Boundaries, nulls, empty inputs, and error paths catch the rest. |
| "Mocking everything" | Over-mocking creates tests that pass but don't catch real bugs. Mock boundaries, not internals. |
| "Test names like test1, test2" | Names should describe behavior: "returns empty array when no items match filter". Self-documenting tests. |
| "No test isolation" | Tests that depend on each other or shared state create flaky test suites that nobody trusts. |
Protocol
Step 1: Gather Test Requirements
If the user hasn't provided details, ask:
- Target: what code needs tests? (function, class, module, API endpoint)
- Language/framework: what tech stack? (JS/TS + Jest/Vitest, Python + pytest, Go, etc.)
- Test level: unit, integration, e2e, or all three?
- Current coverage: any existing tests? What percentage?
- Priority: critical paths first, or comprehensive coverage?
Step 2: Analyze the Code Under Test
Before writing tests, understand the target:
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 Changed ed3c4404597f
- 1mo ago First seen · 473 lines · 70 tokens per session scan A c40f4dd509bc
memstack-development-test-writer is a skill published in the GitHub repository cwinvestments/memstack (425 stars, last pushed today), licensed MIT. It adds 70 tokens to every session and 3,745 once invoked, about $0.0003 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 2026-08-30.
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