Tools

Companion skill for the agent-browser CLI: has the agent load usage matching the installed version to navigate, fill forms, take screenshots and run exploratory tests, and can also drive Electron desktop apps. Install the agent-browser CLI first; from Vercel Labs.

Package manager for macOS and Linux: agents can brew install CLI tools and desktop apps (casks), or use brew bundle to restore a dev environment from a Brewfile.

Terminal multiplexer: run multiple sessions and panes in one terminal, with processes surviving disconnects. Agents use it to host long-running tasks and drive interactive programs, and many parallel multi-agent session tools build on it.

Microsoft's open-source AI quant investment research platform: the qrun command runs dataset building, model training, backtesting and evaluation from a YAML config, with many benchmark models. The official dataset is paused, so prepare market data per the README first.

Drives Alibaba's open-source ocr CLI to review Git changes (working tree, a commit or a branch diff), grouping line-level comments by severity and fixing them on request. Needs an LLM endpoint (Anthropic, OpenAI and other protocols); installs the CLI if missing. By Alibaba.

Collection of 2,400+ installable SKILL.md skills across development, security, cloud and ops, AI, marketing and more, with the AAS Core local MCP and an installer that help agents search, pick skills and preview install plans. Formerly antigravity-awesome-skills.

Official CLI (bru) for the open-source API client Bruno: runs collections stored as plain text in your repo, switches environments, outputs JSON results and imports collections from OpenAPI, making API tests easy to run in CI.

Google's official Firebase plugin: starts the Firebase MCP via firebase-tools to manage projects, Firestore data, Auth users and security rules, and view Crashlytics and Cloud Functions logs. Needs Node.js and a Firebase CLI login.

Connects Claude Code to the clangd C/C++ language server for code intelligence, diagnostics and formatting. Install LLVM/clangd and add it to PATH first. Official Anthropic plugin.

Connects Claude Code to the Pyright language server for static type checking and code intelligence in Python. Install pyright first with npm, pip or pipx. Official Anthropic plugin.

Connects Claude Code to the Eclipse JDT.LS language server so the agent can go to definitions, find references and inspect symbols in Java code. Needs JDK 17+ and jdtls installed first. Official Anthropic plugin.

Wraps Microsoft's Playwright MCP so agents can drive a real browser to navigate, click, fill forms and take screenshots for end-to-end tests and page checks. In Anthropic's official marketplace; needs Node.js.

Three layers of security checks on agent-written code: rule-based warnings on about 25 risky patterns during edits, a model review of the diff at turn end, and an agent tracing cross-file bugs like IDOR and SSRF at commit. Official Anthropic plugin; needs Python 3.8+ and model API access.

Connects Claude Code to the C# language server csharp-ls for code intelligence and diagnostics. Needs .NET SDK 6.0+; install csharp-ls first via dotnet tool or Homebrew. Official Anthropic plugin.

Official Anthropic plugin that reads local session logs in ~/.claude/projects and generates an interactive HTML usage report covering tokens, cache hit rate, subagents, skills and the most expensive prompts, with optimization tips. Needs Node.js.

Connects Claude Code to SourceKit-LSP so the agent can go to definitions, find references and inspect symbols in Swift code. Install the Swift toolchain or Xcode first. Official Anthropic plugin.

Creates or improves Agent Skills from scratch: writes eval cases to test them, runs benchmarks with variance analysis, and tunes descriptions for more accurate triggering. Maintained by Anthropic.

Connects Claude Code to JetBrains' Kotlin language server so the agent can go to definitions, find references and inspect symbols in .kt and .kts files. Install kotlin-lsp first (Homebrew works). Official Anthropic plugin.

Connects Upstash's hosted Context7 remote MCP to fetch current, version-specific docs and code examples for libraries on demand, reducing outdated or invented APIs. No local Node needed; works anonymously, and an API key raises limits. Maintained by Upstash.

Designs and builds MCP servers: first picks a deployment model among remote HTTP, MCPB bundles and local stdio, then guides tool design, auth and in-chat interactive components. Maintained by Anthropic.

Command-line tool for transferring data by URL over 20+ protocols including HTTP(S), FTP, SFTP, WebSocket and MQTT; a staple for agents calling APIs and downloading files. Preinstalled on macOS and most Linux distributions.

Lightweight multi-protocol command-line downloader that fetches in parallel segments from multiple sources over HTTP(S), FTP, SFTP, BitTorrent and Metalink. Resumes downloads, reads URLs in bulk from text files and offers a JSON-RPC interface for scripts or agents.

Accessibility review plugin with an audit command, a UI validation subagent, and WCAG 2.2 and screen reader testing skills. Before design reviews or launch, the agent checks contrast, keyboard use and screen reader support and suggests fixes. For Claude Code; automated checks need Node.js.

Data engineering plugin from the wshobson/agents marketplace: a data engineer subagent, a data pipeline command, and skills for Airflow DAGs, dbt transformations, Spark tuning and data quality, to help build ETL and data warehouses.