MCP Server
Rostyman includes a built-in MCP server that allows AI tools to interact with your API workspace. When running, AI assistants such as Claude Desktop, Claude Code, Cursor, Windsurf, and VS Code Copilot can browse your collections, send requests, manage variables, and more — all through natural language.
Enabling the MCP Server
The MCP server starts automatically when Rostyman launches. To check its status or configure it:
- Open Settings (Ctrl+,) → Integrations → MCP Server
- The status indicator shows whether the server is running, the protocol (HTTP or HTTPS), and the current URL
You can also see server status in:
- The status bar at the bottom of the window (green dot + client count)
- The MCP panel in the right sidebar (Overview tab)
MCP Panel — Overview Tab
The Overview tab in the MCP panel shows the live server state.
Server Card
| Element | Description |
|---|---|
| Status indicator | Green border = running, default border = stopped |
| Running status | "Running — localhost:3100 · 2 clients" or "Stopped" |
| Start / Stop button | Starts or stops the server |
| Settings button | Opens Settings → Integrations → MCP Server |
| Register with Claude Desktop | Auto-registers Rostyman in Claude Desktop's config file |
| Copy Config | Copies the MCP JSON configuration to the clipboard |
Connected Clients Tab
Lists AI agents currently connected via SSE:
| Field | Description |
|---|---|
| Name | Friendly name parsed from user-agent (Claude Desktop, Claude Code, Cursor, Windsurf, VS Code, MCP Remote Bridge, Node.js Client, Python Client) |
| IP | Source IP address of the connection |
| Since | Duration since connection was established (e.g. "2m ago") |
| Disconnect | Force-closes the client's SSE stream |
Click Refresh to reload the client list. The list updates automatically when clients connect or disconnect.
Connected Servers Tab
Lists external MCP servers Rostyman is connected to as a client, with status and tool count. See MCP Client for details.
MCP Panel — Servers Tab
Manages external MCP servers (client connections). See MCP Client.
MCP Panel — Logs Tab
Controls
| Control | Action |
|---|---|
| Search input | Filter log lines in real time |
| Verbose checkbox | Toggle full request/response payloads in logs |
| Clear Logs | Clears the in-memory ring buffer (500 entries max) |
| Open folder icon | Opens the log directory in the file manager |
Log Entry Format
Each line shows: time LEVEL [source] message
- ERROR — red
- WARN — amber
- TOOL — accent color (tool call events with timing)
- INFO — muted
Log Content
Every log entry captures:
- HTTP requests: method, URL, IP address, session ID
- JSON-RPC method calls:
initialize,tools/list,tools/call, etc. - Tool calls: tool name, arguments, result preview, elapsed time (e.g. "ok (42ms)")
- Session lifecycle: initialized, closed, client disconnected
- Auth failures and rate limit hits
Logs are saved to date-based files in {userData}/logs/mcp/. Files older than 30 days are automatically deleted. The stats bar at the bottom shows the file count and total size.
Settings Reference
All settings are in Settings (Ctrl+,) → Integrations → MCP Server.
Port
Default: 3100. To change: edit the port field and press Enter or click away. The server restarts on the new port. If the port is busy, Rostyman automatically tries the next available port.
Access Mode
| Mode | Description |
|---|---|
| Local only (default) | Accepts connections from localhost only. CORS restricted to localhost origins. No auth required. |
| Network | Accepts connections from any device on your network. Requires a Bearer token. Rate limited to 60 req/min per IP. |
Auth Token (Network Mode)
Rostyman generates a cryptographically secure token when Network mode is enabled.
| Action | How |
|---|---|
| View token | Shown partially masked in Settings |
| Copy token | Click the copy icon |
| Regenerate | Click the refresh icon — creates a new token and invalidates the old one |
AI tools must include the token in every request:
Authorization: Bearer your-token-here
TLS / HTTPS
Enable HTTPS for secure connections. Required for Claude.ai web connectors and recommended for Network mode.
Prerequisites: Install mkcert
# Windows
choco install mkcert
# or
scoop install mkcert
# macOS
brew install mkcert
# Linux
# See https://github.com/FiloSottile/mkcert#installation
Setup:
- Rostyman auto-detects mkcert. Click Recheck if it was just installed.
- Click Generate with mkcert to create locally-trusted certificates.
- Toggle TLS on — the server restarts with HTTPS.
Certificates are stored in {userData}/certs/. The server URL and all config snippets automatically switch to https://.
Tunnel Access
Expose your local server to the internet so remote AI tools (including Claude.ai web) can connect.
ngrok:
- Install ngrok from ngrok.com
- Rostyman detects it automatically — a Copy ngrok command button appears
- Run the copied command in a terminal
- Use the generated
https://xxx.ngrok-free.app/mcpURL in your AI tool's config
Cloudflare Tunnel:
cloudflared tunnel --url http://localhost:3100
Use the generated URL in your AI tool's config.
When using a tunnel, keep TLS off — the tunnel provider handles HTTPS at their end.
Connecting AI Tools
Claude Desktop (Recommended: Auto-Register)
- In Rostyman, click Register with Claude Desktop (in the MCP panel Overview tab or in Settings)
- Restart Claude Desktop
Claude Desktop (Manual Config)
Paste into Claude Desktop's config file:
- Windows:
%APPDATA%\Claude\claude_desktop_config.json - macOS:
~/Library/Application Support/Claude/claude_desktop_config.json - Linux:
~/.config/claude/claude_desktop_config.json
{
"mcpServers": {
"rostyman": {
"command": "npx",
"args": ["-y", "mcp-remote", "http://localhost:3100/mcp"]
}
}
}
Restart Claude Desktop after editing the config.
Claude.ai Web
- Set up a tunnel pointing to port 3100 (ngrok or cloudflared)
- Go to claude.ai → Settings → Connectors → +
- Enter the tunnel URL (e.g.
https://xxx.ngrok-free.app/mcp) - All 18 tools appear in the connector's tool list
Copy Config (All Other Tools)
Click Copy Config in the MCP panel to get the JSON snippet formatted for the currently running server (HTTP or HTTPS, correct port).
Available Tools
Rostyman exposes 18 tools in three categories, visible in the Show Tools dialog (accessible from the MCP panel Overview tab or Settings).
Read Tools (8)
| Tool | Description | Parameters |
|---|---|---|
list_collections | Lists all collections in the active workspace | — |
get_collection | Gets collection details with all folders and requests | collectionId |
get_request | Gets full request details (URL, headers, body, auth) | requestId |
search_requests | Searches requests by name, URL, or method (up to 50 results) | query |
list_environments | Lists all environments for a collection | collectionId |
get_environment | Gets environment variables (secret values are masked as ••••••) | environmentId |
get_globals | Gets all global variables for the workspace | — |
get_history | Gets the last 20 executions of a request with status and timing | requestId |
Execute Tools (2)
| Tool | Description | Parameters |
|---|---|---|
send_request | Sends a saved request (by ID) or an ad-hoc request (by method + URL). Resolves variables before sending. | requestId?, method?, url?, headers?, body? |
run_collection | Runs all requests in a collection or specific folder, resolves variables, returns a summary | collectionId, folderId?, environmentId? |
Write Tools (3)
| Tool | Description | Parameters |
|---|---|---|
create_collection | Creates a new empty collection | name |
create_request | Creates a request in a collection | collectionId, name, method, url, folderId?, headers?, bodyMode?, bodyContent? |
set_variable | Sets a variable in environment, collection, or global scope (upserts) | scope (environment/collection/global), scopeId, key, value |
Tools Dialog
Click Show Tools in the Overview tab or Settings to open a searchable dialog showing all tools. Each tool entry displays:
- Tool name (monospace)
- Category badge (Read / Execute / Write)
- Description
- Parameter names (required params in secondary color, optional params ending in
?in muted color)
Resources (4)
In addition to tools, Rostyman exposes 4 MCP resources that AI tools can read directly:
| Resource URI | Description |
|---|---|
rostyman://collections | JSON list of all collections (id + name) in the active workspace |
rostyman://environments | All environments across all collections |
rostyman://globals | All global variables for the workspace |
rostyman://history | Recent request history entries |
Resources are read-only and reflect the current workspace state.
Variable Resolution
When send_request or run_collection is called, variables are resolved in this order (highest priority last):
- Global variables
- Collection variables
- Environment variables (from the collection's active environment, or the
environmentIdparameter)
Built-in variables like {{$timestamp}} and {{$randomInt}} are also resolved.
Troubleshooting
Port already in use
Rostyman automatically tries the next available port. You can also manually change the port in Settings.
Claude Desktop shows no tools
- Verify Rostyman is running and the MCP server is started (green dot in status bar)
- Confirm the port matches in both apps
- Restart Claude Desktop after any config change
- Check the Logs tab for connection or initialization errors
Auth errors in Network mode
- Confirm the token in Rostyman matches the one in your AI tool's config
- The header format must be exactly:
Authorization: Bearer your-token-here - Regenerate the token in Settings if needed and update the AI tool config
Connection drops after idle
In Network or tunnel mode, SSE connections may time out if idle for too long. The AI tool will reconnect automatically on the next request. This is normal behavior.