I built 9 free web tools and printed the entire backend on every page. What should number 10 be?

Description and use

The author built nine lightweight web tools that, without sign‑ups, display their full backend code on the result page, ensuring transparency and reproducibility. They process URLs into Markdown, JSON, YAML, check links, robots.txt, and image alt text, and expose MCP endpoints for agent use.

Problem

Developers need lightweight, no‑sign‑up web tools that expose their full backend code for transparency and reproducibility.

Outcome

The nine tools provide transparent, lightweight web utilities that expose their full backend code, enabling developers to verify, adapt, or extend them without sign‑ups or hidden APIs.

Workflow

• 1. User pastes a URL into the tool’s web form.
• 2. The tool fetches the target page’s server‑rendered HTML.
• 3. It processes the content (e.g., converts to Markdown, JSON, YAML, or checks links).
• 4. The tool returns the processed result and the full source code of its backend on the same page.
• 5. Users can copy the code, run it locally, or integrate it into their own workflows.

Evidence

Every tool prints the complete source code of its own backend, right there on the page.

Source

No signup, no API key, no "start your free trial".

Source

The dead link checker crawls 10 sitemap pages max, though it checks every link it finds on them.

Source