Task runner for
AI agents

Drop markdown files in a folder, number them, and run. Each file is one task sent to an AI agent. When you need loops, retries, or conditional logic — add an .ash script. Start simple. Grow as needed.

Deterministic Control, AI Execution

AI agents handle ambiguity — understanding intent, making judgments. They're bad at sequencing, branching, and retrying. Ash handles the structure. Agents handle the content.

Guaranteed Sequencing

Tasks run in numbered order every time. No "what should I do next?" — the script decides. The agent executes.

Bounded Autonomy

The agent decides how to do its step. Ash decides whether the step happens, how many times, and what comes next.

Repeatability

A weekly report, a recurring audit, a batch job — same process every time, even when the content of each step varies.

Execution Efficiency

Pre-determined control flow runs at CPU speed. AI time is spent only where it adds value — on the content of each step.

Workflows as Code

Review content, audit compliance, publish updates — all live in files you commit, version, share, and re-run. Not buried in chat threads.

Agent-Agnostic

OpenCode, Claude Code, Aider, or a custom tool. Define in a config file. Swap providers without touching your workflows.

How Ash Works

Drop markdown files in a folder, number them, and run. Each file is a task sent to an AI agent. Output flows between steps.

tasks/

Step 1: Create a folder of tasks
tasks/
├── 01-research.md
├── 02-implement.md
├── 03-review.ash
└── 04-deploy.md

Terminal

Step 2: Run — agents execute each task in order
$ ash --agent opencode tasks/
[1/4] 01-research.md → opencode sonnet-4
[2/4] 02-implement.md → claude-code claude-sonnet-4
[3/4] 03-review.ash (shebang: codex)
[4/4] 04-deploy.md → opencode haiku-flash
4 tasks, 4 passed

Getting Started

Built-in support: opencode, claude-code, aider, codex, gemini-cli, kimi, and more. See supported agents for the full list and default configs.

Use --agent to specify which agent to run with:

ash --agent opencode ./tasks

The tasks/ folder contains numbered .md files — each file is one task sent to the agent, executed in sorted order. Drop in an .ash file when you need loops, retries, or conditionals. See How Ash Works for the expected folder layout.

If you add a new agent after ash was already installed, run:

ash discover

Any CLI-based agent can be configured manually via ash.yml:

agents:
  my-tool:
    type: local-cli
    cmd: my-tool
    message_flag: "--prompt"
    yes_flag: "--yes"

When You Need Full Orchestration

Markdown tasks handle simple agent calls. Drop in an .ash file when a single prompt isn't enough — variables, conditionals, shell commands within one step. Standalone scripts give you the full language: loops, retry, parallelism, functions. Same runtime, same state passing. Just add power as you need it.

Variables, Strings & Shell

MSG = "hello"
ITEMS = ["a", "b", "c"]
FIRST = ITEMS[0]
print "count: ${len(ITEMS)}"
working_dir = $(pwd)

Agent Calls

do "Review this code" with opencode

try {
  do "Fix the bug" with fixer
} fail {
  do "Retry: ${stderr}"
} upto 3

Control Flow

for FILE in FILES {
  do "Review ${FILE}"
  if $? != 0 { exit 1 }
}

exec npm test
if $? == 0 {
  print "all good"
}

Functions & Composition

fn review(path) {
  do "Review ${path}" with opencode
}

include "helpers.ash"
review("src/main.rs")

For .ash scripts, declare the agent with a shebang:

#!opencode:1.0

do "Review src/" with opencode

For .md tasks, optionally set the agent in YAML frontmatter:

---
agent: opencode
model: sonnet
---

# Task Title

The prompt content goes here...

Playground

Write and run Ash scripts in your browser, or use the REPL for interactive experimentation. The built-in js-echo agent echoes your prompt back.

Script
Output Status: ready
Click "Run" to execute the script.
loading WASM...