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Kosmo Sidekick

Kosmo Sidekick

josefosaurus

|
3 installs
| (0) | Free
Spec-driven development with Claude Code CLI. Generate requirements, design, and tasks from a goal — then run each task as an isolated AI agent.
Installation
Launch VS Code Quick Open (Ctrl+P), paste the following command, and press enter.
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Kosmo Sidekick

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

New Spec input

Sidebar — tasks grouped by spec, with live status

Sidebar with task list

CLI picker — choose your AI agent on first use

CLI picker quick select

Output — live agent tool-use stream with cost

Output channel during task execution


Requirements

  • VSCode 1.75+
  • At least one supported AI CLI installed and authenticated:
CLI Install
claude Claude Code
gemini Gemini CLI
codex OpenAI Codex CLI
opencode OpenCode
deepseek DeepSeek CLI
llm llm by Simon Willison
sgpt ShellGPT

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]/:

File Contents
requirements.md User stories + EARS acceptance criteria
design.md Architecture, components, data models
tasks.md Numbered checkbox task list

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.

Kill a running task

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


Spec file format

tasks.md uses a strict format that Kosmo parses:

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

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


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

Command Description
Kosmo: New Spec Generate spec from a goal string
Kosmo: Start Task Run selected task via Claude Code
Kosmo: Kill Task Stop running task
Kosmo: Refresh Tasks Manually refresh sidebar
Kosmo: Select AI CLI Change which CLI is used for spec generation
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