REPL Mode

When you run your app with no arguments, Repl starts an interactive session. The same routes your CLI uses are available interactively — no separate implementation.

Starting a session

$ myapp
>

The > prompt signals REPL mode. Type any command from your graph:

> client list
Alice
Bob

> client 42 show --json
{ "id": 42, "name": "ACME" }

> exit

Scoped navigation

app.Context(...) creates sub-scopes. You can enter a scope and run commands relative to it:

> client
[client]> list
Alice
Bob

[client]> 42
[client/42]> show
Id: 42, Name: ACME

[client/42]> ..
[client]> ..
>

• Enter a scope by typing its name (or a scoped value like 42).
• Go up with ...
• The prompt shows your current position.

Ambient commands

These are always available in REPL mode regardless of your command graph:

Command	Description
help	List commands in current scope
help <route>	Describe a specific command
exit	End the session
clear	Clear the screen
..	Go up one scope level

History and completion

• Up/Down arrows navigate command history.
• Tab triggers autocomplete for routes and parameters (requires UseDefaultInteractive()).
• History is in-memory by default and does not persist across sessions. Inject a custom IHistoryProvider to add persistence (file, database, or any backing store).

Customizing the prompt

app.WithBanner("""
    Welcome to MyApp REPL.
    Type 'help' to list commands.
    """);

Driving from scripts

REPL mode can be driven by a script using --answer:* options — useful for demos and deterministic testing:

myapp --answer:1=Alice --answer:2=alice@example.com

The --answer:N flag pre-fills interactive prompts in order.

Next step

→ MCP Mode