Reference

Command line

panto dispatches on its first argument. Some names are true subcommands (sessions, models, auth, bootstrap, update, lua, help); the flag forms start the agent itself, either interactively or in one-shot print mode.

Command	Does
panto	Start a new interactive conversation in the current directory.
panto --resume [<id>]	Resume the most recent session, or a specific session by id prefix.
panto -c	Alias for bare `--resume`.
panto -p [prompt]	Run one non-interactive turn, print assistant text, exit 0/1.
panto sessions	List saved sessions for this directory.
panto models sync	Fetch models.dev and rebuild the base `models.toml`.
panto auth …	Show auth status, log in, or log out.
panto bootstrap [--force]	Prepare the bundled Lua / luarocks runtime and exit.
panto update	Install or refresh every rock listed in `extensions.rocks`.
panto lua [args…]	Run the embedded Lua interpreter.
panto --version	Print the panto version.

Starting a session

pantoStart a fresh interactive conversation.

panto --resume [<id>]Resume the latest or a specific saved session.

panto -p, --print [<prompt>]Run one turn without the TUI.

Interactive mode requires a tty on stdin and stdout. Print mode does not: the prompt can come from the flag argument or from piped stdin, and the command prints only the assistant text before exiting.

-c, --continue

Alias for bare --resume.

-m, --model <provider:alias>

Override the model for this run. A bare alias also works when it is unique across providers.

--effort <level>

Override the reasoning level for this run. This beats both models.toml knobs and [defaults] reasoning.

--no-extensions

Skip the Lua runtime entirely. The core still starts, but because the shipped tools are extensions the agent runs with no tools.

Unknown arguments are errors now

Agent-mode flag parsing is strict. An unrecognized argument prints an error and exits instead of being ignored.

panto sessions

panto sessionsList sessions for the current directory.

Sessions are stored per working directory. The listing is newest-modified first and prints the shortest unambiguous id prefix, the modified timestamp, message count, model, and last user message:

panto · sessions

$ panto sessions

ID MODIFIED MSGS MODEL LAST MESSAGE

0197c2a4 2026-07-01 14:32 18 sonnet add json mode to stats

0197bfe1 2026-06-30 09:11 6 gpt-5 clean up the parser errors

~/.local/share/panto/sessions/--Users-travis-Code-ledger--

If there are no sessions yet, panto prints no sessions for <cwd> and then the directory it would use.

panto models

panto models syncFetch models.dev and rebuild the base models.toml.

The sync command looks at the providers that resolved from your layered config, maps each one to a models.dev catalog entry, optionally intersects that with the provider's own live /models listing, and writes the result to the base-layer models.toml at $XDG_DATA_HOME/panto/models.toml (or ~/.local/share/panto/models.toml).

panto · models sync

$ panto models sync

synced 42 model(s) across 3 provider(s) to ~/.local/share/panto/models.toml

Your user and project models.toml layers still sit on top and win.

panto auth

With no action, panto auth defaults to status.

panto auth status

Show every configured auth session. API-key sessions report resolved or unresolved (key/env missing); OAuth sessions report whether they are logged in and when the current access token expires.

panto auth login <name>

Run the OAuth device flow for the named session and persist the resulting token set.

panto auth logout <name>

Delete the stored token set for the named session.

panto bootstrap

panto bootstrap [--force]Run the runtime bootstrap pipeline, then exit.

Bootstrap stages the base agent tree, creates the generated base config as needed, and prepares the versioned luarocks tree under the data home. The normal agent startup path runs the same bootstrap automatically.

panto updateInstall or refresh the rocks listed in extensions.rocks.

panto update is the explicit “go hit luarocks again” command. Startup only installs missing rocks; changing a version pin or forcing a re-resolve is what update is for.

panto lua

panto lua [args…]Run the embedded Lua interpreter with panto's runtime wired in.

This is the same embedded Lua build panto uses internally, with package paths and luarocks configured the same way a session sees them. It is handy both for experiments and for driving luarocks manually:

shellbash

panto lua my-script.lua
panto lua -e 'arg[0]="luarocks"; require("luarocks.cmd").run_command("install","lpeg")'

Slash commands

Lines beginning with / are handled locally inside the TUI and never sent to the model.

Built in

/help, /quit, /model, /reasoning, /new, /resume, /status, and /compact.

Extension-defined

Lua extensions can register more slash commands with panto.ext.register_command.

Environment

Variable	Effect
ANTHROPIC_API_KEY	Consumed by the default Anthropic provider.
OPENAI_API_KEY	Consumed by the default OpenAI provider.
PANTO_DEBUG	When non-zero, route `std.log` output to `<data home>/debug/<session>.log` instead of the terminal.
PANTO_SESSION_DIR	Override the base sessions directory. panto still appends one encoded subdirectory per working directory.
XDG_CONFIG_HOME	Locates the user config and user extensions directories.
XDG_DATA_HOME	Locates the data home: base config, base models, sessions, auth cache, agent tree, and rocks.