Kosmo Sidekick

Spec-driven development for VSCode — powered by any AI CLI agent. Describe a feature, get a full requirements + design + task breakdown, then run each task as an isolated AI agent.

Inspired by Kiro.

How it works

1. Describe what you want to build
2. Kosmo generates requirements.md → design.md → tasks.md for your feature
3. Run tasks — each one spawns a Claude Code agent with injected spec context
4. Track progress in the sidebar and directly in tasks.md

Screenshots

New Spec — describe your goal

Sidebar — tasks grouped by spec, with live status

CLI picker — choose your AI agent on first use

Output — live agent tool-use stream with cost

Requirements

• VSCode 1.75+
• At least one supported AI CLI installed and authenticated:

Note: Task execution always uses claude (Claude Code CLI) — it provides the Read/Write/Edit/Bash tools that run your tasks. The CLI picker only affects spec generation.

Installation

1. Clone this repo
2. npm install && npm run compile
3. Press F5 to launch the Extension Development Host

Or install the .vsix:

npm run package
code --install-extension kosmo-sidekick-*.vsix

Usage

Generate a spec

Open the Command Palette (⌘⇧P) → Kosmo: New Spec

Enter a goal like:

"Add rate limiting to the REST API using a Redis sliding window"

On first use, Kosmo detects which AI CLIs are installed and asks you to pick one. The choice is saved globally — change it anytime via Kosmo: Select AI CLI.

Kosmo writes three files to .kosmo/specs/[spec-name]/:

Run a task

Click ▶ next to any [ ] task in the sidebar or in tasks.md via CodeLens.

A Claude Code subprocess runs the task in your workspace CWD with the full spec as context. The Output Channel streams every tool call in real time. When done, the checkbox updates to [x] automatically.

If a task has _Requirements: 1.1, 2.3_, only the referenced subsections of requirements.md are injected into the prompt — keeping context tight for large specs.

Kill a running task

Click ⏹ next to any [~] task. The marker reverts to [ ].

Discover

Kosmo: Discover queries your codebase with a freetext question via subq or miami CLI (must be in PATH). Output streams to a channel; you can copy it or feed it directly into a new spec.

Edit spec files

Opening any .kosmo/specs/**/*.md file uses Kosmo's custom editor — an editable textarea with line numbers, a step-navigation toolbar (Requirements › Design › Task list), and sync/continue buttons. Use the floating Open Preview button for rendered markdown.

Spec file format

tasks.md uses a strict format that Kosmo parses:

- [ ] 1. Task title
  - implementation detail
  - another detail
  - [model:haiku]
  - _Requirements: 1.1, 2.3_

States: [ ] pending · [~] in progress · [x] done

Model tiers — add [model:haiku], [model:sonnet], or [model:opus] to any detail line to control which model runs that task. Default is sonnet. Use haiku for cheap/fast tasks (linting, formatting) and opus for complex reasoning tasks.

Project context

For best results, fill in the generated CLAUDE.md at your project root. Every agent subprocess receives it as context alongside the spec files.

# Project Context
## Tech Stack
## Architecture Notes
## Coding Conventions

Extension commands