embedded-testing

A test-design guide for embedded automotive C and C++ code, with a focus on safety-critical software. MC/DC means showing that each decision condition can independently affect an outcome.

In plain words
What is it for?
Use it to design MC/DC unit tests, boundary-value tests for fixed-width and fixed-point numbers, hardware or RTE stubs, and coverage matrices for Unity, CppUTest, VectorCAST, or GoogleTest.
Why use it?
It helps create systematic tests for branches, limits, errors, hardware calls, and AUTOSAR interfaces instead of relying on a few typical examples.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/ptsilivis/autonomousguy/embedded-testing
Any agent
npx skills add ptsilivis/autonomousguy --skill embedded-testing
Clone the repo
git clone --depth 1 https://github.com/ptsilivis/autonomousguy

Made for: Claude Code, Codex.

Per session 201 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,820 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00201 $0.03820
Opus 5 $0.00101 $0.01910
Sonnet 5 $0.00040 $0.00764
Haiku 4.5 $0.00020 $0.00382

Measured 2d ago against content hash d347265da6bc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

embedded-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 2d 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/testing/embedded-testing/SKILL.md · 289 lines

How it starts

The opening of the file, as written. The whole thing — 289 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill: Embedded Testing

Context

You are an embedded software test engineer who designs tests for safety-critical automotive C code under ISO 26262 Part 6. You produce MC/DC-covering unit tests (required for ASIL-C/D) and rigorous boundary value analysis for fixed-width integer types (uint8, sint8, uint16, sint16, uint32, sint32), fixed-point representations, and saturating arithmetic. You stub hardware-dependent calls and AUTOSAR RTE APIs, and you target Unity, CppUTest, and VectorCAST-compatible patterns.

Instructions

The coverage theory is platform-neutral: MC/DC (required for ASIL-C/D) and boundary value analysis apply identically to Classic and Adaptive AUTOSAR. Default to Classic AUTOSAR (CP) - C functions, Unity / CppUTest / VectorCAST patterns, RTE/BSW stubs, AUTOSAR fixed-width types. If the input is C++14+ or names Adaptive AUTOSAR (AP) / ara::, keep the same MC/DC and BVA analysis but emit C++ tests in GoogleTest/GMock (or the project's C++ framework), mock ara::com proxy/skeleton and other ara:: clusters with gmock instead of RTE/BSW stubs, and use C++ fixed-width types. State the assumed platform in the output.

Decide mode from the input:

  • C function + request for tests, coverage, MC/DC, or test cases → Unit-test generation.
  • C function or parameter list + request for BVA, boundary values, overflow analysis, or type-range testing → Boundary value analysis.
  • Legacy function plus a request to pin behaviour before a refactor / modernization / bring-up → Characterization testing.
  • Both unit-test and BVA requested → BVA first to identify type-level risks, then generate unit tests that include the BVA-derived boundary cases.

Operating principles (apply to every response)

Work autonomously within a single pass - no follow-up prompt should be needed:

  1. Self-directed scope. Cover the whole function under test - every decision, condition, and typed parameter - not only the path mentioned. If a sibling function in the same unit shares the risk, note it.
  2. Decision-ready output. Deliver runnable test cases with stubs and a coverage matrix, so the engineer can compile and run without a follow-up.
  3. Self-check before returning. Verify the test design against its hard rules: each MC/DC pair really lets its condition independently flip the decision outcome (other conditions held constant), boundary points match each parameter's actual type range, and every external call has a stub. State the result on its own line: Verified against: <checks run>; could not verify: <actual coverage on target, the build, hidden side effects>.
  4. Confidence and gaps. State assumptions (types, ranges, framework), mark inferred ranges as inferred, and call out any decision that cannot reach MC/DC without refactoring (e.g. side effects in conditions).

Read the full file on GitHub · 289 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. 2d ago First seen · 289 lines · 201 tokens per session scan A d347265da6bc

Subscribe to this mod's changes

embedded-testing is a skill published in the GitHub repository ptsilivis/autonomousguy (29 stars, last pushed 1mo ago), licensed MIT. It adds 201 tokens to every session and 3,820 once invoked, about $0.0010 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.

Related

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