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Convert your API into MCP Server in seconds. No-code, GUI based MCP Framework that creates, deploys and serves MCP servers with built-in auth, realtime logs and telemetry. Make your product available in LLMs today!

Which is more popular?
Based on our record, CodePen seems to be more popular. It has been mentioned 513 times since March 2021.
Website, pricing, platforms and company facts side by side.
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| Website | codepen.io | hasmcp.com |
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| Company | — | Startup from the United States · 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


No description of CodePen yet.
API to MCP Server Automated OpenAPI Mapping: Streamlines integration by converting OpenAPI (v3.0/3.1) and Swagger documentation directly into LLM-ready Model Context Protocol (MCP) tools. This eliminates the need for manual "glue code," ensuring accurate, no-code setup in seconds. MCP Auth Native...
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Walkthroughs and reviews on video.
What Is Codepen?
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Public API to MCP Server (step-by-step guide)
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How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing CodePen and HasMCP.
HasMCP's answer:
Built-in auth, realtime logs, telemetry, token optimization with interceptors and secret management make HasMCP win over all competitors.
HasMCP's answer:
Go, Vue.js, Taildwincss, Redis, Postgres, Sqlite
HasMCP's answer:
Developers SaaS owners
HasMCP's answer:
I was working on MCP Servers and I found it is hassle to create one using the tools/frameworks. But not only the creation process, the servers had be downloaded via npx or python at that time. As an alternative, I had to wrap an existing endpoint by writing tons of code. Another thing is the change on the official MCP specs was lightning fast and are not simple just to update your server, you have to write code again to catch it up with the latest spec.
After understanding the underlying protocol communication, I decided to remove this bottleneck from developers life and democratize to access MCP Server with just sharable URL instead of arbitrary local code execution.
Another big challenge was token optimization; I shouldn't have been just returning the what endpoint returns, that was including a lot of unnecessary sometimes confidential information, so an interceptor idea was born. HasMCP supports Jmespath and JS interceptors that you can modify the payload before returning to the client. Either you need to remove a PII column or just prune the data that you need, HasMCP is here to help.
Authentication is one of the other pain points in MCP world; HasMCP supports OAuth2 authentication with elicitation when the OAuth2 client credentials are defined in the provider. So, no more thinking about how I am going to authenticate the user. It is ready to use with just standard OAuth2 client input values. The access/refresh tokens are stored in encrypted format in the session storage. If your API does not support OAuth2, I got you covered too: Your users can define secrets (encrypted environment values) to send specific header values on tool calls.
Realtime access logs and metrics gives you full visibility on what is happening behind the scene. What is the request/response payload in JSONRPC 2.0 format, what MCP client/server side notifications have been sent. What methods have been called, all available in realtime only (not stored)!
When we expose MCPs to LLMs we give full control on the tools, another killer feature of HasMCP is toggling the tools what is being exposed to LLM in realtime. You can simply toggle the ones and authorize access for LLMs and this takes immediate affect, so you can kill a tool or add new one on the fly. This increases the security and give the user to have granular control what is allowed or not. While talking to one LLM you can expose a subset of read only tools whereas some superusers would need to use the write endpoints, this selection is just a toggle in HasMCP. Once you created an API provider, you can create unlimited servers from it, you can just focus on the secure design of your system.
HasMCP is API first, and majority of these functionality also available in opensource community edition. It is time to make your product 7/24 available to ChatGPT, Gemini, VSCode, Cursor, Claude, and all other LLMs that has MCP client with realtime governance. Today is the day to build an MCP server for your product!
HasMCP's answer:
HasMCP is the first GUI MCP Server framework that supports request/response altering with interceptors.
Share your experience with using CodePen and HasMCP. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Codepen is a social network for developers to show off their work, ask and answer questions, and exchange ideas. It's like a Reddit for coding and design, with a large community of talented web developers.
Codepen is a social development environment that allows developers to showcase their work and experiment with HTML, CSS, and JavaScript in a collaborative space. Codepen’s focus on visual and interactive development...
Codepen is a social development environment for front-end designers and developers. Build and deploy a website, show off your work, build test cases to learn.
We have no reviews of HasMCP yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


> I vividly remember IE and many hacks to have css elements properly working in it… The common advice now is to only use CSS that is supported in the last two major versions of each major browser. You can check any css property's support... - Source: Hacker News / 2 months ago
Thank you, heartfelt... For sharing an artwork, a miracle! Just in case, have you considered publishing the work at platforms as CodePen, where genius Artists/People express their art, too, as you?: // https://codepen.io/. - Source: Hacker News / 3 months ago
Embed on DEV: If you prefer CodePen embed, create a Pen with that HTML and add to the post as: {% codepen https://codepen.io//pen/ %}. - Source: dev.to / 12 months ago
Tracking HasMCP since Feb 2026.
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