Extensions | beginning-harness

What Extensions Are

Extensions are named capability families that bgng can inspect, diagnose, and set up. They are distinct from skill bundles and MCP servers — an extension can combine CLI prerequisites, repo-native skills, optional MCP servers, project setup actions, and diagnostics under one user-facing name.

Inspect extension support:

bgng extensions list
bgng extensions show beads
bgng extensions status
bgng extensions doctor

Machine-readable output is available with --json.

Current Extensions

Parallel

Parallel support is CLI+skills-first. Selecting the extension for one project writes semantic config under <project>/.agents/bgng/config.json; bgng write then derives the four Parallel skills for that project without requiring global skill curation.

Default shared skills:

parallel-web-search
parallel-web-extract
parallel-deep-research
parallel-data-enrichment

Those skills assume parallel-cli is installed and authenticated separately.

Install parallel-cli:

curl -fsSL https://parallel.ai/install.sh | bash

Authenticate:

parallel-cli login
parallel-cli auth

Preview setup:

bgng extensions setup parallel --dry-run

Enable the Parallel skills for the current project:

bgng extensions add parallel

Enable project-scoped Parallel MCP as well:

bgng extensions add parallel --mcp

bgng extensions status parallel and bgng extensions doctor parallel report missing CLI or MCP prerequisites.

MarkItDown

MarkItDown support is CLI+skills-first. Selecting the extension for one project writes semantic config under <project>/.agents/bgng/config.json; bgng write then derives the markitdown-document-conversion skill for that project.

The guarded install path is:

uv tool install --python 3.12 'markitdown[all]'

Preview setup:

bgng extensions setup markitdown --dry-run

Run setup and choose interactively whether to install the missing CLI:

bgng extensions setup markitdown

For scripts:

bgng extensions setup markitdown --install
bgng extensions setup markitdown --no-install

bgng extensions status markitdown and bgng extensions doctor markitdown report missing runtime, missing skill, and smoke-check failures.

Beads

Beads support is CLI-first and project-scoped. bgng checks for bd, reports whether the current project has .beads/, can run Beads setup recipes, and can record Beads extension config for the project.

Install bd through one of the upstream-supported paths:

brew install beads
npm install -g @beads/bd
curl -fsSL https://raw.githubusercontent.com/steveyegge/beads/main/scripts/install.sh | bash

Preview setup:

bgng extensions setup beads --dry-run

Run setup:

bgng extensions setup beads

Useful flags:

Flag	Description
`--target=codex,claude,cursor`	Select Beads setup recipes
`--stealth`	Pass Beads stealth setup mode to `bd`
`--skip-bd-init`	Skip `bd init`
`--skip-bd-setup`	Skip `bd setup`
`--include-skill`	Set `extensions.beads.includeSkill: true` to derive `beads-task-tracking`

Setup never runs bd init --force or bd doctor --fix by default. Beads MCP remains optional.

Add vs. Setup

Use bgng extensions add <name> when you only want to record project config. Use bgng extensions setup <name> when the extension has setup work or runtime prerequisites to inspect.

bgng extensions add markitdown --dry-run
bgng extensions add parallel --skip-skills
bgng extensions setup markitdown --install