Best Oss AI Skills & MCP Servers

Agentic HubSpot CLI + MCP server. Covers ~all documented public endpoints (1180 across 55+ command domains). Reachability is tier/scope/auth-model gated — UI-only surfaces and deprecated APIs excluded. Enterprise safety rails, self-hosted.

Text search and replace across files — regex search, multi-file replace, grouped results.

Package version intelligence — latest version, diff, changelog, audit across npm/pypi/github/gitlab.

Rename refactoring — rename symbols across files, rename files with import updates, bulk rename with preview.

Slack MCP without OAuth. 21 tools (16 read/write Slack + 2 workflow profile primitives + 3 hosted-brain upgrade stubs). Free OSS or hosted (free tier no card; $9/mo Pro = unlimited; morning DM rolling out Q2 2026).

Model Context Protocol (MCP) server integration for @ttoss/http-server

Cross-agent permission policy specification for AI coding agents

API-first MCP server for multi-model cross-review with unanimous convergence gates.

Deterministic installer for the undoc MCP server, skills, and hooks across Claude Code, Cursor, Codex, and Claude Desktop.

HMRC Making Tax Digital API client and MCP server — reusable across projects

Create a Context Hub — a personal AI context layer shared across any MCP client (Claude.ai, Claude Code, Claude App, ChatGPT, Perplexity, Cursor, and more). One command to scaffold, deploy, and connect.

Extension manager for AI coding agents — install skills, subagents, slash commands, and MCP servers across Claude Code, Codex, Cursor, Copilot, and more.

Local-first MCP server for cross-agent AI memory. One SQLite + FTS5 corpus across Claude Code, Cowork, Cursor, Continue, Zed, Obsidian, and Telegram — passively captured, verbatim, searchable from any MCP-compatible client.

🧴 Sync your AI agent configurations and rules across platforms with ease

Universal Skills MCP Server — load Markdown skills from arbitrary folders, lazy-by-design, cross-tool (Claude Code / Codex CLI / any MCP client).

Planu — MCP Server for Spec Driven Development with native Rust acceleration for hot paths. Cross-platform (Linux/macOS/Windows, x64/arm64, glibc/musl).

MIND MCP Server — 28 tools. The most complete AI memory layer with the Focus → Project → Outcome → Task hierarchy (mind_focuses + extended mind_life with item_type/parent_id/focus_id and cross-account project sharing via share/list_shares/revoke_share), d

Log10x MCP Server — per-pattern log cost attribution, root-cause investigation, pasted-batch triage, archive query/backfill, and cross-pillar correlation against customer metric backends (Grafana Cloud, Mimir, Thanos, AMP) with structural validation that

Deployment tool and support utility for AI context. Copies agents, skills, commands, rules, and behaviors into the paths each AI platform reads (Claude Code, Codex, Copilot, Cursor, Warp, OpenClaw, and 6 more) so one source of truth works across 10 platfo

Model Context Protocol server for retailerapi.com — unified product data across major US retailers (Walmart, Amazon, eBay, Target, Best Buy, Lowe's, Home Depot) plus universal URL passthrough for every Shopify store and any retailer that ships Product JSO

Universal AI CLI extension manager - install MCP servers, plugins and skills across Claude Code, Gemini CLI and Codex in one command

Model Context Protocol server providing access to Tatum's comprehensive blockchain API across 130+ networks with 13 tools

Cross-agent permission policy specification for AI coding agents

Planu — MCP Server for Spec Driven Development with native Rust acceleration for hot paths. Cross-platform (Linux/macOS/Windows, x64/arm64, glibc/musl).