Claude Code gets more useful the less you add to it.
Every extra slash command and MCP server you install becomes something you have to remember mid-flow. Most of them won't survive your next setup refactor. But a handful of repos have genuinely changed how I work across projects, across teams, across the last six months of my own tool churn.
Rule of thumb: install one, use it for a week, then decide whether to keep it. Never install a bundle.
For enforcing discipline
superpowers
A set of skills that forces structured workflow before code. The headline behavior: if there's no test for a function, the skill will refuse to write the implementation — or delete what's already there. It's annoying the first time and life-changing by week two.
Pair it with a TDD-friendly test runner and you've quietly built the guardrails your team meetings keep trying to legislate.
everything-claude-code
30+ agents, 100+ skills, dozens of slash commands. Don't install the whole thing — you'll drown. Pull three or four that match how you actually work. The kitchen-sink catalog is useful precisely because you can shop it without committing.
claude-code-best-practices
Read this one, don't install it. A set of patterns distilled from people who ship with Claude Code daily. Half an hour of reading; a couple of weeks of reversed bad habits. Worth doing before you customize anything else.
For giving Claude more context
repomix
Packs an entire codebase into a single AI-readable file with one command. The magic isn't the compression — it's that Claude stops asking clarifying questions about structure and just answers. The cost of pasting a full repo into context dropped from "annoying" to "free."
Works best on repositories under ~50k lines. Above that, prefer selective includes.
context7
Injects live, up-to-date library documentation into your prompts. If you've ever caught Claude hallucinating an API that was renamed two versions ago, this is the fix. It pulls current docs at prompt time, so you stop shipping code that references phantom functions.
claude-session-restore
Restores full context from previous sessions by walking git history. Handy when you're picking up a branch you haven't touched in a week and don't want to re-explain every decision. The generous file-size ceiling means it keeps working long after your transcript gets unwieldy.
For integrations
modelcontextprotocol/servers
The canonical MCP servers repo. The GitHub server alone is worth the install — read repos, open issues, manage PRs, all in natural language from inside Claude Code. Once you've used it, typing gh pr view manually starts to feel quaint.
claude-code-action
The official GitHub Action for running Claude Code in CI. Not demo-ware — actual PR reviews, automated, on every push. Twenty minutes to set up, and the payoff compounds every time a teammate forgets to think about edge cases.
For browsing the ecosystem
awesome-claude-code
The community's curated index. The rule for new entries is that the PR must come from Claude itself — which sets a quality bar and limits the firehose. Browse here before you build something; half the time the skill you want already exists.
awesome-claude-skills
50+ community skills grouped by category. Same spirit as awesome-claude-code, scoped to skills. Read before you build.
How to actually adopt these
The biggest mistake I see: installing six things at once. Every new tool changes how you prompt, how you think about context, and how you interpret Claude's output. When multiple variables move together, you can't tell which ones helped.
A suggested order:
- Start with
repomix. Lowest friction, biggest immediate payoff. - Add
context7next. Stops hallucinations without you having to prompt around them. - Add one discipline skill — either
superpowersor a carefully chosen subset ofeverything-claude-code. Give it two weeks before you judge it. - Once those are habits, layer integrations — the MCP GitHub server, then the GitHub Action.
Four tools, deployed in order, is more useful than twelve installed the same afternoon.
Also worth a mention
The list above is about repos. A few things that aren't repos but sit right next to them — equally worth your time:
anthropics/anthropic-cookbook. Canonical recipes for the Anthropic API. Not Claude-Code-specific, but anyone who ends up wrapping Claude in their own tooling ends up reading this.- Hooks in
.claude/settings.json. The single highest-leverage customization most people haven't tried. A few lines of shell inPostToolUsecan auto-commit after successful edits, re-run tests, validate formatting, or kick off a deploy. Read the hooks docs before you build a custom agent — you'll often find a five-line hook replaces it. - A real project
CLAUDE.md. The markdown file at your repo root that Claude reads on every session. Most developers treat it as a throwaway; spend an hour writing a genuine one — architectural notes, house rules, domain vocabulary — and you'll cut back-and-forth by half. - Cost visibility. Tools like
ccusagewatch token spend in real time. At daily-use cadence, a $0.50/day habit silently becomes $180/year. Putting a number on your workflow changes how you prompt.
These aren't in the main ten because they're not repos — they're adjacent practices. Equally important, different shape.
The goal
A setup that disappears into your workflow, so that when you're writing, you're writing — not managing tools.