tckit: Skill for Claude Code

.claude/skills/tc-build-test-loop/SKILL.md

tc-build-test-loop is a skill for Claude Code from georgeturneruk/tckit. It costs 162 tokens per session (1,944 once invoked), scanned A, original, MIT.

A build, deployment, and testing workflow for TwinCAT, software used to program industrial control systems. It analyses projects before building, then supports building, deploying, running TcUnit tests, and checking results through TcKit.

In plain words
What is it for?
Checking TwinCAT projects, building PLC solutions, deploying them to targets, running tests, and iterating on failures.
Why use it?
It catches certain project problems before a slower build and provides a repeatable way to investigate build and test failures.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

This is georgeturneruk/tckit's own configuration. It tells Claude Code how to work on tckit itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything tckit configures →

Reuse

Borrowing it

Nothing to install: this file belongs to georgeturneruk/tckit. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/georgeturneruk/tckit/main/.claude/skills/tc-build-test-loop/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/georgeturneruk/tckit

Made for: Claude Code.

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 tc-build-test-loop

README.md
[![agentmods](https://agentmods.dev/badge/skills/georgeturneruk/tckit/tc-build-test-loop/github.svg)](https://agentmods.dev/skills/georgeturneruk/tckit/tc-build-test-loop)
Your own site
<a href="https://agentmods.dev/skills/georgeturneruk/tckit/tc-build-test-loop"><img src="https://agentmods.dev/badge/skills/georgeturneruk/tckit/tc-build-test-loop/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 tc-build-test-loop

Your own site · 80×15
<a href="https://agentmods.dev/skills/georgeturneruk/tckit/tc-build-test-loop"><img src="https://agentmods.dev/badge/skills/georgeturneruk/tckit/tc-build-test-loop.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 162 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,944 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 $0.00162 $0.01944
Opus 5 $0.00081 $0.00972
Sonnet 5 $0.00032 $0.00389
Haiku 4.5 $0.00016 $0.00194

Measured 8d ago against content hash d0c4035c642a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

tc-build-test-loop 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 8d 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.

.claude/skills/tc-build-test-loop/SKILL.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Build / deploy / test loop

Analyse first

Before the first Build of a cycle, call AnalyseProject(projectPath, severity: "warning"). It parses the project files offline, so it needs no XAE and returns in under a second against a build's tens of seconds, and it catches a class of defect a green build cannot rule out: a function block instance on a call stack whose state resets every call, floating-point equality, retention that cannot retain, a global with two writers.

  • severity: "warning" keeps naming suggestions out of the way. Raise it to suggestion only when the user asked about conventions.
  • Fix what it reports before building. These are not build errors, so building first tells you nothing about them.
  • Check skipped and config_warnings. A short finding list next to a long skipped list means coverage was partial, not that the project is clean.
  • One pass per cycle, not per fix. Re-run it after the build-fix loop settles if you changed much.

This does not replace the build. It is cheaper, so it goes first.

Build-fix loop

  1. Call Build(project_path) with an absolute path to the .sln (or .tsproj). For multi-PLC solutions, pass plc_name=<consumer> on the same call; see "Multi-PLC builds with library references" below.
  2. If success: true:
    • If a docs_warning field is present, this is non-fatal — note it for the user but do NOT loop on it.
    • Proceed to deploy/test as the user requested.
  3. If success: false, take the first error in the JSON list. Read the offending file via GetPouItem if needed. Fix that one file only.
  4. Rebuild. Do not batch fixes across files.
  5. Two-strikes rule. If the same error message on the same file/line persists after a second fix attempt, STOP. Present the error, your two attempts, your hypothesis, and ask the user.

Where targetAmsId comes from

Deploy, StartRuntime, and RunTests take a required targetAmsId parameter; there is no env-var or config-file default. If you don't know the target, ask the user rather than guessing or hunting through the filesystem.

Read the full file on GitHub · 85 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. 8d ago First seen · 85 lines · 162 tokens per session scan A d0c4035c642a

Subscribe to this mod's changes

tc-build-test-loop is a skill published in the GitHub repository georgeturneruk/tckit (5 stars, last pushed 14d ago), licensed MIT. It adds 162 tokens to every session and 1,944 once invoked, about $0.0008 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.