Developer Tools.

A free, open-source tool for generating test files with chosen sizes, repeatable recipes and expected-result manifests.

Good to know

macOS, Windows · Free download: Free, GPL-3.0 software with public downloads.

A free beta scanner for public website configuration, with 19 passive checks and shareable reports.

Good to know

Web · Free with no signup; the homepage describes 19 passive checks.

A bilingual directory of public GitHub resources for AI agents, with repository, ownership, license, and installation context.

Best for

Developers building AI-agent workflows

SEMAPRAX explores coding-agent changes built on stable declaration IDs, typed program context, and revision checks.

Good to know

Free download: Apache-2.0 pre-release source is documented for experiments and prototypes.

A read-only GitHub Action that records a bounded evidence packet for one public, non-security issue.

Good to know

Free and paid options: The Action is free and open source; a separate source-linked decision brief is fixed at $19 for an eligible public non-security issue.

Static Form Inspector flags common HTML form mistakes in the browser or during a GitHub Actions run.

Good to know

Web · Free: Browser inspection is free and requires no account; a separate fixed-price repair service is offered.

Browse agent skills by client or category, inspect listings, and copy installation commands for supported coding tools.

Good to know

Free: The registry describes itself as free and open source.

Connect an MCP client to Chromium for navigation, page reading, forms, screenshots, and browser diagnostics.

Best for

Developers already working with MCP

Nexus Shell combines routine remote-server work in a Mac app, with a free personal tier and a one-time Pro license.

Good to know

macOS · Free and paid options: The personal-use Free edition is perpetual; Pro is a one-time lifetime purchase, with a seven-day Pro trial for direct downloads.