Interactive TUI

mcpal tui opens a three-pane curses-style browser over every MCP server that mcpal can see (owned + discovered). Useful when you do not remember a tool's exact name or schema and want to call it without composing a shell command first.

┌─ Servers ──────────────┬─ Detail ───────────────────────────┐
│ > opencode:linear   ⚡ │ Tools (12)  Resources (3)  Prompts │
│   cursor:notion     🔒 │   list_issues                       │
│   ev                ●  │   create_comment                    │
│   mcp.context7.com  ⚡ │   add_assignee                      │
│   fs (stdio)        ●  │   …                                 │
├─ Output ───────────────┴─────────────────────────────────────┤
│ $ connect opencode:linear                                    │
│ ✓ connected to opencode:linear (12 tools)                    │
│ $ tool call opencode:linear list_issues                      │
│ ✓ opencode:linear list_issues                                │
└ Tab cycle · Enter open · / filter · ? help · q quit ─────────┘

Layout

The three panes are Sidebar (servers), Detail (tools / resources / prompts of the selected server, or a tool schema / result), and Output (a 200-line ring of command echoes plus live notifications from connected servers).

Icons in the sidebar tag the transport:

● stdio
⚡ HTTP, no auth required
🔒 HTTP, OAuth required

Key map

Key	Action
`Tab` / `Shift+Tab`	cycle pane focus
`j`/`k`, `↓`/`↑`	move selection
`gg` / `G`	jump to top / bottom
`Enter`	drill in (sidebar → detail tabs → schema / form)
`Esc`	drill back, or close a modal
`/`	filter the sidebar; `Esc` clears, `Enter` accepts
`c`	call the selected tool (Detail focus, Tools tab)
`l` / `Right`	next tab in Detail (Tools → Resources → Prompts)
`b`	open a bearer-token input for the selected server
`?`	toggle help overlay
`q`, `Ctrl-C`	quit

Calling a tool

c on a tool opens a form modal whose fields come from the tool's inputSchema. Each field is labelled with its type (str, int, num, bool, json) and an * when required. Tab cycles fields. Enter submits. The terminal renders the response inline in the Detail pane; the Output pane gets a one-line echo with a ✓ or ✗.

If the schema declares object or array, the field stores a raw JSON literal — paste it directly.

Notifications

mcpal forwards every notification it sees from a connected server into the Output pane:

progress becomes → progress N/M.
log becomes → log <level>: <message>.
list-changed / resource-updated become a generic → <kind> line.

The buffer is bounded at 200 lines.

Building without the TUI

The TUI is gated behind the tui feature, which is on by default. To get a smaller mcpal binary without ratatui, crossterm, tui-input, and tui-textarea:

cargo install mcpal --no-default-features

mcpal tui then prints "unrecognized command" and exits 2.

What's not in v1

In-TUI OAuth flow. If a server returns 401, drop out and run mcpal auth login <ref> --oauth in another shell.
: command bar.
Persistent layout / theme overrides.

File issues at https://github.com/pawelb0/mcpal/issues.

mcpal — curl for MCP