Golem Interactive REPL (Rust)

The golem repl command starts an interactive REPL for testing and scripting agents. It supports both an interactive mode and a script execution mode.

Interactive Mode

golem repl --language rust

Starts a Rust REPL with all agent client types preconfigured in scope. You can get or create agent instances, invoke methods, and see logs streamed during invocations.

Note: The Rust REPL is slow interactively because it recompiles on each input. For quick interactive exploration, consider using the TypeScript REPL instead (golem repl without --language). For scripted test sequences, the Rust REPL works well.

Example: Invoking a counter agent

let c1 = CounterAgent::get("c1").await.unwrap();
c1.increment().await;
c1.increment().await;

Built-in Commands

The REPL provides built-in commands that mirror CLI functionality. Commands accept both . and : prefixes:

• .build / :build — build the project
• .deploy / :deploy — deploy components
• .help / :help — show available commands

Script Mode

To run a Rust test script:

1. Create the script file (e.g., test.rs) with Rust REPL syntax
2. Execute it immediately with golem repl:

golem repl --script-file test.rs --language rust --yes

The --yes flag auto-confirms any prompts. The script has the same scope as the interactive REPL — all agent client types are available.

Run the script after creating it, unless the user explicitly asked not to.

Example script (test.rs)

let c2 = CounterAgent::get("c2").await.unwrap();
c2.increment().await;
c2.increment().await;

Recommended REPL Language

For Rust projects, the Rust REPL is available and lets you use the same language as your agents in scripts. However, the TypeScript REPL (golem repl without --language) is faster for interactive use because it doesn’t need to recompile.

Note: the REPL can interact with agents written in any language (Rust, TypeScript, Scala, MoonBit) — the REPL language is independent of the agent’s implementation language. All agent types are available regardless of the agent’s source language.

Available REPL Languages

Prerequisites

• The Golem server must be running (golem server run)
• Components must be deployed (golem deploy)