Sezzlee OpenAPI

Name: Sezzlee OpenAPI
Author: sezzlee

by sezzleeversion 1.0.0i★ 1 (Stars for the whole repo)iRuns on your computer

Registry nameio.github.sezzlee/openapi

How to install

Overview

Description from the maker (original English)

Expose an OpenAPI document to agents as a search-first tool catalog over your existing API.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Connection: Runs on your computer
Transport: stdio
Category: Developer tools
You need to fill in: SEZZLEE_OPENAPI_CONFIG

Install

Pick the AI app you use, then copy the settings.

Passed 2/2 checks · Runs on your computer

First: which AI do you use?

ClaudeWeb · app · phoneChatGPTWebClaude CodeTerminalCursorCode editorVS CodeCode editorOtherOther apps

Pick your app and the steps appear below.

Works with Claude, with some setup first

You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time) · Only the Claude desktop app (Windows or Mac), not the web or phone

Install Node.js
One time only; it works for every server that needs Node.js
Open the Node.js download page ↗
Done
Sign up and create a Sezzlee OpenAPI key
Open the maker’s site, sign up and create an API key for the next step. It may cost money.
Open the Sezzlee OpenAPI site ↗
Done
Open the Claude desktop app’s settings file
SettingsDeveloperEdit Config
Done

Paste these settings and save the file

{
  "mcpServers": {
    "openapi": {
      "command": "npx",
      "args": [
        "-y",
        "@sezzlee/openapi-mcp"
      ],
      "env": {
        "SEZZLEE_OPENAPI_CONFIG": "your-value"
      }
    }
  }
}

Paste the key only into the app’s field, never into a chat or to anyone

Done

Quit Claude and open it again
Done
Try it
Use Sezzlee OpenAPI and tell me what you can do for me, then show me one thing
✓ If Claude says it is using Sezzlee OpenAPI or shows a Sezzlee OpenAPI tool in the answer, you are connected

Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version

ChatGPT cannot connect Sezzlee OpenAPI yet

Sezzlee OpenAPI runs on your computer, but ChatGPT can only connect servers that run on the web

What you can do instead

A · Use an app that can connect Sezzlee OpenAPI

Steps for Claude →You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time) · Only the Claude desktop app (Windows or Mac), not the web or phone
Steps for Claude Code →You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)
Steps for Cursor →You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)
Steps for VS Code →You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)

B · Others in Developer tools that work with ChatGPT

Picked from the most used in the same category, only ones that connect by address with no key

Sentry✓ ChatGPT
Front-End Checklist✓ ChatGPT
Compiler Explorer✓ ChatGPT

Works with Claude Code, with some setup first

You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)

Install Node.js
One time only; it works for every server that needs Node.js
Open the Node.js download page ↗
Done
Sign up and create a Sezzlee OpenAPI key
Open the maker’s site, sign up and create an API key for the next step. It may cost money.
Open the Sezzlee OpenAPI site ↗
Done
Open Terminal
Mac: press Command+Space and type Terminal · Windows: open PowerShell
Done
4
Paste this command and press Enter
```
claude mcp add openapi --env SEZZLEE_OPENAPI_CONFIG=your-value -- npx -y @sezzlee/openapi-mcp
```
Replace “your-value” with your key before pressing Enter
Paste the key only into the app’s field, never into a chat or to anyone
Done
Type /mcp in Claude Code
You should see Sezzlee OpenAPI listed as connected
Done
Try it
Use Sezzlee OpenAPI and tell me what you can do for me, then show me one thing
✓ If Claude Code says it is using Sezzlee OpenAPI or shows a Sezzlee OpenAPI tool in the answer, you are connected

Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with Cursor, with some setup first

You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)

Install Node.js
One time only; it works for every server that needs Node.js
Open the Node.js download page ↗
Done
Sign up and create a Sezzlee OpenAPI key
Open the maker’s site, sign up and create an API key for the next step. It may cost money.
Open the Sezzlee OpenAPI site ↗
Done
Click this button to open Cursor
Open in Cursor
Cursor asks you to confirm; click Install
Done
Fill in your key
In the Sezzlee OpenAPI settings, SEZZLEE_OPENAPI_CONFIG is empty; add your key and save
Paste the key only into the app’s field, never into a chat or to anyone
Done
Open the AI chat in Cursor in Agent mode
Done
Try it
Use Sezzlee OpenAPI and tell me what you can do for me, then show me one thing
✓ If Cursor says it is using Sezzlee OpenAPI or shows a Sezzlee OpenAPI tool in the answer, you are connected

Menu names checked against Cursor’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Works with VS Code, with some setup first

You need a Sezzlee OpenAPI key (sign up on the maker’s site, may cost money) · Install Node.js on your computer first (one time)

Install Node.js
One time only; it works for every server that needs Node.js
Open the Node.js download page ↗
Done
Sign up and create a Sezzlee OpenAPI key
Open the maker’s site, sign up and create an API key for the next step. It may cost money.
Open the Sezzlee OpenAPI site ↗
Done
Click this button to open VS Code
Open in VS Code
VS Code asks you to confirm; click Install
Done
Fill in your key
In the Sezzlee OpenAPI settings, SEZZLEE_OPENAPI_CONFIG is empty; add your key and save
Paste the key only into the app’s field, never into a chat or to anyone
Done
Open the AI chat in VS Code in Agent mode
Done
Try it
Use Sezzlee OpenAPI and tell me what you can do for me, then show me one thing
✓ If VS Code says it is using Sezzlee OpenAPI or shows a Sezzlee OpenAPI tool in the answer, you are connected

Menu names checked against VS Code’s help page on Nov 11, 2026 · your screen may differ slightly by app version

Other apps that use MCP, such as Windsurf, Zed or Gemini CLI, each add servers differently. See how in the app list.

See every app that uses MCP →

JSON settings are under “For developers” below

Stuck? Ask people who use Sezzlee OpenAPI💬 Discussion →

For developers: Terminal commands and JSON settings

Installed on your computer

Claude Code

claude mcp add openapi --env SEZZLEE_OPENAPI_CONFIG=your-value -- npx -y @sezzlee/openapi-mcp

Claude Desktop (claude_desktop_config.json)

{
  "mcpServers": {
    "openapi": {
      "command": "npx",
      "args": [
        "-y",
        "@sezzlee/openapi-mcp"
      ],
      "env": {
        "SEZZLEE_OPENAPI_CONFIG": "your-value"
      }
    }
  }
}

Cursor (~/.cursor/mcp.json)

{
  "mcpServers": {
    "openapi": {
      "command": "npx",
      "args": [
        "-y",
        "@sezzlee/openapi-mcp"
      ],
      "env": {
        "SEZZLEE_OPENAPI_CONFIG": "your-value"
      }
    }
  }
}

VS Code (mcp.json)

{
  "servers": {
    "openapi": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@sezzlee/openapi-mcp"
      ],
      "env": {
        "SEZZLEE_OPENAPI_CONFIG": "your-value"
      }
    }
  }
}

Values you fill in

SEZZLEE_OPENAPI_CONFIG required env
Path to the server config file

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

At a glance

GitHub stars i: 1 (Stars for the whole repo)
This repo holds several MCP listings; its stars count once in rankings
Downloads per weeki: 57/wk
Licence i: No licence stated
Connection: Runs on your computer
Transport: stdio
Latest versioni: 1.0.0
Categoryi: Developer tools
Published to registryi: Oct 15, 2026
Code last changedi: Nov 10, 2026
Maker: sezzlee
Packages: npm: @sezzlee/openapi-mcp
Repo: sezzlee/mcp
Website: docs.sezzlee.app
Registry status: Active

Which apps can use it

Based on how this server connects and on each app’s own docs, checked Nov 10, 2026.

Run on your computer in

Claude Goose LM Studio Msty Studio Cherry Studio Cursor VS Code + GitHub Copilot Visual Studio Windsurf (Devin Desktop)Zed Kiro Cline Continue JetBrains AI Assistant Claude Code Codex CLI Gemini CLI OpenCode nodecode Warp LibreChat Raycast

All apps, with pros and cons →

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 11, 2026

✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account sezzlee, which owns the repo
✓ Pass
Still maintained
Code last changed yesterday
… Not checked yet
Has a licence
We have not read this repo from GitHub yet
– Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
– Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
… Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints

Discussion

Ask, share a tip or report that it does not work. Sorted by what people marked helpful.

No posts yet. Be the first to ask or share.

Posts here are written by users, not the PopNx team.

User reviews

No reviews yet

Compared with others in Developer toolsi

More stars than 0% of the other 5756 servers in this category
Published to the registry more recently than 53% of the other 5756 servers in this category
Basic checks equal to or better than 100% of the other 5756 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Sezzlee OpenAPI safe?

It passed 2 of 2 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: SEZZLEE_OPENAPI_CONFIG

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed yesterday, and the latest version (1.0.0) reached the registry 27 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: REA, Netdata, Front-End Checklist

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:↓ Downloads per weeki★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

REA

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Runs on your computer

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Netdata

Real-time infrastructure monitoring with metrics, logs, alerts, and ML-based anomaly detection.

by netdataWidely used★ 81.3KUpdated 7 days ago

Runs in the cloud

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Front-End Checklist

Review frontend code and live pages against 386 quality-gated web development rules.

by thedaviddiasWidely used★ 74.7KUpdated 37 days ago

Runs in the cloud

Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

@sezzlee/openapi-mcp

MCP server that exposes an OpenAPI (Swagger 2.0 / OpenAPI 3.0–3.2) document as sezzlee's search-first tool catalog — search_tools, load_tool, invoke_tool, read_result — over a remote backend, calling it with fetch.

Status: 1.0.0, stable. Install with npm install -g @sezzlee/openapi-mcp or run it with

npx -y @sezzlee/openapi-mcp; the binary is sezzlee-openapi.

How this differs from the embedded SDK

The NestJS SDK sits inside your backend process: it discovers endpoints from your own controllers/routes and replay each MCP call through your existing pipeline, so your authentication and authorization run exactly as they do today.

openapi-mcp is a separate service. It has no access to a backend's process or pipeline — it reads the backend's OpenAPI document to learn what operations exist (the ingestion rules), and calls the backend over the network for every invocation, attaching a credential it resolves itself (how a credential is chosen and written). This is the only path for a backend that has no embedded SDK integrated into it.

Everything an embedded SDK declares in code, a document declares in one x-sezzlee extension per operation, and a host that cannot edit the document declares under operations in this config: selection, tool name, prefix, behaviour hints, argument curation, variants, families, search terms and revisions (the x-sezzlee extension). A backend that routes many capabilities through one endpoint (POST /Rest/InvokeDynamicMethod/{methodId}) lists them in that operation's x-sezzlee.family; each member becomes its own tool, with its own name, description and body, and the dispatch key stays hidden.

Quick start

The server reads its configuration from the file named by SEZZLEE_OPENAPI_CONFIG. Build the package first (this repository never runs @sezzlee/core's consumers against a stale dist):

pnpm turbo run build --filter=@sezzlee/openapi-mcp

A minimal config — a local document, opt-in selection so at least one operation is exposed, default stdio transport:

"source": "./openapi.json", "selection": { "default": "include" } }

SEZZLEE_OPENAPI_CONFIG=/absolute/path/to/config.json node packages/servers/openapi-mcp/dist/cli.js

source is either a path (resolved relative to the config file's own directory) or an http(s):// URL. On startup the server ingests the document, builds the catalog, prints a one-line-per-diagnostic-code summary to stderr, and then serves stdio or listens for streamable HTTP, depending on transport.kind.

A config that fails validation, or that names an environment variable that is not set, stops the process with a message on stderr and exit code 2. A document that ingests with a fatal diagnostic, or a catalog with a fatal diagnostic (name_collision, invalid_name, ambiguous_selection, …), stops it with exit code 1.

Configuration

All keys below are read from the SEZZLEE_OPENAPI_CONFIG JSON file and validated with a zod schema (src/platform/config.ts) that rejects unknown keys.

Key	Type	Default	Notes
`transport.kind`	`"stdio"` \	`"http"`	`"stdio"`	—
`transport.host`	string (`http` only)	`"127.0.0.1"`	Must stay loopback (`127.0.0.1`, `::1`, `localhost`) unless `tokenExchange` is configured — see below
`transport.port`	int, 0–65535 (`http` only)	`8787`	—
`transport.path`	string starting with `/` (`http` only)	`"/mcp"`	—
`transport.resource`	url (`http` only)	required	The OAuth protected-resource identifier advertised at `/.well-known/oauth-protected-resource`
`transport.authorizationServers`	array of url, min 1 (`http` only)	required	—
`transport.allowedHostnames`	array of string (`http` only)	`[]`	Extra `Host` header values accepted, on top of the localhost defaults
`tokenExchange`	object	not configured	RFC 8693 token exchange; required for an `http` transport to authenticate a caller (see Rules)
`tokenExchange.tokenEndpoint`	url	required	—
`tokenExchange.clientId`	string	required	—
`tokenExchange.clientSecret`	`{ fromEnv: string }`	required	—
`tokenExchange.clientAuth`	`"basic"` \	`"post"`	`"basic"`	`client_secret_basic` or `client_secret_post`
`tokenExchange.audience`	string	not sent	—
`tokenExchange.resource`	url	not sent	—
`tokenExchange.scope`	string	not sent	—
`tokenExchange.schemes`	array of string, min 1	required	The security scheme names the exchanged token satisfies
`source`	string, non-empty	required	A local file path (relative to the config file) or an `http(s)://` URL to the OpenAPI document
`reload.intervalSeconds`	integer ≥ 10	not set	Re-reads `source` this often, plus up to 10% jitter. Conditional on the last `ETag`/`Last-Modified` for an `http(s)` source; a body identical to the served one is ignored
`reload.onSignal`	boolean	`true`	`SIGHUP` re-reads `source`. Without a `reload` block the document is read once at startup and `SIGHUP` keeps its default action
`baseUrl`	url	not set	Replaces the document's root `servers`
`serverVariables`	record\	not set	Overrides for the document's server variable defaults
`hoistPathPrefix`	string starting with `/`	not set	A leading path segment moved from every route into the base URL
`outputSchema`	`"document"` \	`"omit"`	`"document"`	`omit` for a backend whose responses do not match its document
`requestBodyRequired`	`"document"` \	`"always"`	`"document"`	`always` treats an undeclared `requestBody.required` as `true`
`strict`	boolean	`false`	Raises `openapi_document_invalid` from a warning to a fatal diagnostic
`selection.default`	`"include"` \	`"exclude"`	`"exclude"`	Whether an operation is exposed when no rule matches it (opt-in by default)
`selection.rules`	array of `{ route?, method?, decision }`	`[]`	`route`/`method` are matched the same way the embedded SDKs match a controller route
`operations`	record\	`{}`	Laid over each operation's `x-sezzlee` field by field; a key that names no operation is fatal. A field here may not also be set through `names`, `searchTerms` or `revision.operations`

| names | record\ | {} | Overrides a tool's name; the value must match `^[a-z][a-z0-

Only the beginning is shown; read the rest in the repo

Sezzlee OpenAPI

Overview

What you can do with it

Install

Install Node.js

Sign up and create a Sezzlee OpenAPI key

Open the Claude desktop app’s settings file

Paste these settings and save the file

Quit Claude and open it again

Try it

What you can do instead

Install Node.js

Sign up and create a Sezzlee OpenAPI key

Open Terminal

Paste this command and press Enter

Type /mcp in Claude Code

Try it

Install Node.js

Sign up and create a Sezzlee OpenAPI key

Click this button to open Cursor

Fill in your key

Open the AI chat in Cursor in Agent mode

Try it

Install Node.js

Sign up and create a Sezzlee OpenAPI key

Click this button to open VS Code

Fill in your key

Open the AI chat in VS Code in Agent mode

Try it

Installed on your computer

Values you fill in

At a glance

Which apps can use it

Related guides

What it can do

Basic checksi

Maker matches the repo

Still maintained

Has a licence

Endpoint responds

Sign-in with OAuth

No hidden instructions in tool descriptions

Discussion

User reviews

Compared with others in Developer toolsi

Common questions

Alternatives

REA

Netdata

Front-End Checklist

README from the maker

@sezzlee/openapi-mcp

How this differs from the embedded SDK

Quick start

Configuration