verification-before-completion Skill for Claude: What It Does and How to Install It

Stops Claude from saying work is done, fixed or passing until it has run the check and read the real output.

Installs: 260.9K; on skills.sh
Stars: 310.6K; on GitHub
Updated: Oct 2026; last repo commit

verification-before-completion makes Claude prove a claim before it makes it. The rule: no completion claims without fresh verification evidence. Before it says tests pass, a build works or a bug is fixed, Claude must name the command, run it in full, read the output and exit code, and only then report.

It applies before any success claim, before commits and PRs, and before moving to the next task or delegating. Words like "should", "probably" and early "Great!" or "Done!" are red flags. When a subagent reports success, Claude checks the diff instead of trusting the report. It is a single SKILL.md with no scripts.

Good for

Developers tired of "should work now" from an AI assistant
Teams that commit or open PRs from AI-written changes
Anyone delegating work to subagents

Install verification-before-completion

Claude Code

Copy this prompt.

Install the verification-before-completion skill in Claude Code. Run this command:

npx skills add https://github.com/obra/superpowers --skill verification-before-completion

Then check that it loaded and tell me how to use it.

2
Paste it into Claude Code. It shows the change and asks before running it.

Requires Node.js.

From its listing on skills.sh. Source.

What's in the skill

When it loads

Use when about to claim work is complete, fixed, or passing, before committing or creating PRs - requires running verification commands and confirming output before making any success claims; evidence before assertions always

Sections in SKILL.md

Overview
The Iron Law
The Gate Function
Common Failures
Red Flags - STOP
Rationalization Prevention
Key Patterns
When To Apply

Key facts

Author: obra
Repo: obra/superpowers (skills/verification-before-completion)
Installs on skills.sh: 260,920 (Nov 2026)
GitHub stars: 310,635 (Nov 2026)
License: MIT
Last repo commit: Oct 29, 2026
Files in the skill folder: 1 including SKILL.md
skills.sh audits: Gen Agent Trust Hub: pass, Socket: pass, Snyk: pass

What it includes

No completion claims without fresh verification evidence
The Iron Law
Five steps: identify the command, run it, read the output, verify the claim, then claim
Runs code · The Gate Function
Maps each claim (tests pass, build succeeds, bug fixed) to what actually proves it
Common failures table
Hedging words and early celebration that mean Claude has not verified
Red flags
Good and bad examples for tests, builds, requirements and delegation
Key patterns

From the official docs

Permissions

Low risk

It makes Claude run your own test, lint and build commands, so it is only as safe as those commands.

What it can do

Read your data
Create and change things
Delete things
Read-only mode

Watch out for

It runs whatever verification commands your project has
Check that your test and build commands do not deploy or change shared data.

Questions

How do I install verification-before-completion?

Use the install box above. It is one skill in the obra/superpowers repo.

What does it actually change?

Claude has to run the relevant command in the same message before claiming success, and show the evidence. A linter pass does not count as a build pass, and a past run does not count at all.

Does it need an API key or scripts?

SKILL.md mentions no key, and the skill folder holds only SKILL.md.

Is it safe?

SKILL.md tells Claude to run the verification command (tests, linter, build) before claiming success, so what it runs is whatever commands your project has. The skill adds no scripts, so check that those commands are safe to run.

How is it different from requesting-code-review?

This skill makes Claude check its own claims against fresh command output. requesting-code-review sends the change to a separate reviewer subagent. They check different things and can be used together.

Information

updated Nov 2, 2026

Repository: obra/superpowers
Folder: skills/verification-before-completion

obra/superpowers skills.sh

Sources

Docs, issue trackers and discussions this page is built from.

Show all 2

verification-before-completion SKILL.md · github.com
requesting-code-review SKILL.md · github.com