Adds stdio inheritance to prevent Node.js from dropping console output after 8192 characters due to premature stdout pipe closure before output finishes flushing. Without this, calls like this would truncate after 8192 characters, leading to broken json output:
```
npx --node-options=--inspect -y @modelcontextprotocol/inspector --cli --config .mcp.json --server notion --method tools/list
```
```
# notion mcp server
"notion": {
"//": "doppler needs to expose OPENAPI_MCP_HEADERS (and NOTION_TOKEN within it)",
"command": "bash",
"args": [
"-c",
"doppler run -p 'mcp' -c \"user_${MCP_USER:-$USER}\" -- npx -y @notionhq/notion-mcp-server"
]
},
```
You can see this in their [openapi spec](https://github.com/makenotion/notion-mcp-server/blob/main/scripts/notion-openapi.json), which powers their MCP server.
Test 30 now expects an error when multiple servers exist, even with
"default-server" present, aligning with the simplified logic that only
auto-selects when there's exactly one server.
Only auto-select when there's exactly one server in the config file.
Removes special handling for "default-server" naming convention.
Addresses review feedback from @ochafik on PR #661
- Add --transport option to command line parser
- Support --transport stdio/sse/http flags
- Convert 'http' to 'streamable-http' internally
- Fix transport type conversion for CLI mode
- Pass URL as command for SSE/HTTP configs instead of empty string
- Update runCli to pass transport type flag when needed
- Update tests to expect connection errors for non-existent SSE/HTTP servers
- Auto-select server when --config is used without --server
- Use 'default-server' if it exists in config
- Use single server if only one is defined
- Show helpful error if multiple servers exist without default
- Add tests for all default-server scenarios
- Remove web client launch tests from CLI test suite
- Add CLI-mode tests for SSE and streamable-http configs
- Keep only tests that use --cli flag as intended
- Add tests for config files with different transport types (stdio, sse, streamable-http)
- Add test for backward compatibility with configs missing type field
- Verify transport and serverUrl options are correctly parsed from config files
- All 36 tests pass
When launching the inspector with --config, automatically set the transport
dropdown and server URL based on the config file contents. This eliminates
the need to manually switch between stdio/sse/streamable-http in the UI.
- Use discriminated union for ServerConfig to properly type different transports
- Detect transport type and URL from config, pass via query params
- Maintain backwards compatibility for configs without explicit 'type' field
- Add comprehensive tests for the new functionality
Improves UX by making the config file the single source of truth for
server settings.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
When running the inspector with command-line arguments (e.g.,
`npx @modelcontextprotocol/inspector node build/index.js arg1 arg2`),
the command and arguments were not being properly passed through to
the UI for pre-filling.
Changes:
- cli.ts now passes command and args to start.js
- start.js uses --command for the command and --args for arguments
- Server parses the new --command parameter
- /config endpoint returns correct values for UI pre-filling
This ensures the UI correctly displays the command and arguments
passed on the command line instead of showing old localStorage values.
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
At the moment, the CLI tool expects that remote MCP servers, either
using SSE or streamable HTTP transport, have certain endpoints or
fragments -- `/sse` and `/mcp`, respectively. This is not part of the
MCP spec, nor should it be expected.
I also added a check to make sure a URL is provided if STDIO isn't
picked, erroring out if not.
