Test Confidence

What it does

When your agent uses it

• Development work in your project

Example prompts

• “/test-confidence”

Requirements

• A credential in ANTHROPIC_API_KEY
• Pre-approved tools (allowed-tools): Bash(git *), Bash(bundle exec rspec *), Bash(cat *), Bash(find *), Bash(wc *), Bash(head *), Bash(tail *), Bash(grep *), Bash(bin/test-confidence *)

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

1. 1Finds changed files (branch diff vs main for PR branches, local diff on main)
2. 2Hashes the diff and checks tmp/test-confidence/ for a cached plan; reuses if found
3. 3Otherwise sends the diff + spec tree + touched directories to Opus 4.7 in one call
4. 4Opus returns a plan: risk level, ordered test list, confidence milestones
5. 5Script executes the plan, showing yellow progress bar toward 99%
6. 6At 99%, bar turns green. Safe to commit.
7. 7With --full, continues running remaining tests toward 100%

What it can do on your machine

Read from SKILL.md and the folder at commit 9de1e01. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Bash(git *)
  • Bash(bundle exec rspec *)
  • Bash(cat *)
  • Bash(find *)
  • Bash(wc *)
  • Bash(head *)
  • Bash(tail *)
  • Bash(grep *)
  • Bash(bin/test-confidence *)

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are bash).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names these keys or tokens, usually read from environment variables:

  • ANTHROPIC_API_KEY

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Test Confidence loads about 738 tokens when it runs. Until then it costs about 28 tokens; SKILL.md has 342 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~28

When it runs · the whole SKILL.md, loaded when a task matches

~738

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NoteMentions a .env fileSKILL.md:20

  ANTHROPIC_API_KEY` is auto-sourced from `.env` if not exported.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from antiwork/gumroad at commit 9de1e01, republished under its MIT licence (© antiwork). 342 words, ~738 tokens.

name

test-confidence

description

AI-driven test execution. Opus decides what to run and how confident to be, based on your diff.

allowed-tools

Bash(git *), Bash(bundle exec rspec *), Bash(cat *), Bash(find *), Bash(wc *), Bash(head *), Bash(tail *), Bash(grep *), Bash(bin/test-confidence *)

argument-hint

--full to run to 100% | --strict to halt on pre-existing failures

bin/test-confidence            # Run to 99%, stop. Skips past pre-existing failures.
bin/test-confidence --full     # Run to 100%
bin/test-confidence --strict   # Halt on any failure, including pre-existing

© antiwork, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .agents/skills/test-confidence of antiwork/gumroad.

Open the folder on GitHubat commit 9de1e01