Tools

Pulls Yahoo Finance data for free via yfinance: company profiles, financials, analyst estimates, news, option chains, fund holdings and sector rankings, plus candlestick charts. No API key, just uv. Data may be delayed; have investment conclusions reviewed by a professional.

Posit's official R package connecting R to Claude Code and other agents: register your own R functions as tools and run them in your open R session, using its data. Out of the box it only switches sessions; add the btw package for docs lookup and data inspection tools. Requires R.

Wraps Shapely, GeoPandas, PyProj, Rasterio, PySAL and other GIS libraries so agents can run geometry and overlay analysis, reproject coordinates, process rasters (e.g. NDVI), do spatial statistics and make maps, and fetch boundaries, land cover and satellite imagery. Needs Python 3.10+ and uv.

Lets agents run the CodeRabbit CLI to review local changes, listing bugs and security issues by severity, and fix unresolved CodeRabbit comments on a PR after you confirm each one. Maintained by CodeRabbit; needs the CLI installed and signed in. Free tier available.

MongoDB's official plugin: runs the MongoDB MCP locally via npx and adds skills for query generation, index tuning, schema design, and full-text and vector search. Connects to self-hosted or Atlas databases with a connection string.

MongoDB's official skill library covering document model design, driver connection setup, query optimization, natural-language query generation, Atlas full-text and vector search, and stream processing. Works alongside the MongoDB MCP Server.

Miro's official plugin with the Miro remote MCP and three skills: draw codebase explanations on a board, run visual code reviews on the board, and turn board docs, diagrams and prototypes into development specs. Needs OAuth with a Miro account.

Official skills from US broker Alpaca: teach agents to backtest, place and check paper trades, plus developer guides for Broker API account opening, funding and reconciliation. Needs an Alpaca API key (paper trading uses no real money) and the Alpaca CLI; results need professional review.

Microsoft Translator's translation quality tool: GPT scores each sentence using MQM error categories or a direct score; --list_mqm_errors shows error types and severity. Needs line-aligned source and target files, Python and an OpenAI or Azure OpenAI key (paid); a translator should still review.

Slack's official plugin: connects the Slack-hosted MCP to search messages and files, send or schedule messages, and read and write canvases. Includes commands for channel summaries and standup reports, plus skills for building Slack apps. Requires workspace admin approval.

Gives agents 250+ Financial Modeling Prep endpoints: financials, valuation and technical indicators, insider and congressional trades, SEC filings and earnings calendars. Needs an FMP API key (free tier); connect to the author's hosted URL or run locally on Node.js 25.3+. Results need expert review.

Connects any FHIR-compliant EHR server (e.g. the Epic sandbox or HAPI) to agents to search, read, create and update patient clinical data in plain language, with SMART on FHIR auth. By WSO2. Needs a FHIR server URL, access token and uv; clinicians must review results.

Microsoft's official MCP: query Clarity traffic, behavior metrics and session recordings in plain language, filtered by device, browser, country and more, to dig into landing page conversion. Needs Clarity installed on your site, a data export API token and Node.js.

Connects to the St. Louis Fed's FRED database: search and pull 800,000+ macroeconomic time series (GDP, unemployment, inflation, interest rates) with built-in year-over-year and period-over-period changes. For macro research, investing and teaching. Needs a free FRED API key and Node.js.

Jenkins plugin that turns Jenkins itself into an MCP server: agents can list jobs, trigger and rerun builds, page through and search build logs, and view test results and SCM info. Hosted in the official jenkinsci organization; authenticates with a Jenkins API token over Basic auth.

Runs the AccessLint rule engine against a live page and returns a worklist of WCAG 2.2 violations, each with its DOM selector, source file and line when mapped, evidence and a suggested fix. Locates without editing; sets up a debuggable Chrome and runs the CLI via npx.

Diffs a live page's accessibility violations against a baseline, stashing uncommitted changes by default or comparing with a branch, and reports new, fixed and pre-existing WCAG issues with selectors and fixes. Locates only, no edits. Runs AccessLint's Chrome and CLI tools via npx.

Sonar's official plugin bringing SonarQube checks into the agent coding loop: secrets-scanning hook, issue fixing, quality gates, coverage and dependency risk; with Vortex analysis on, every edit is checked. Needs SonarQube (free Community Build works), the sonar CLI and Docker.

From Twilio Labs: exposes Twilio's public APIs (SMS, voice, phone numbers, Serverless and more) as MCP tools generated from its OpenAPI specs, with filtering by service or tag. Needs a Twilio API key; marked as a proof of concept.

Shapes the agent's own replies rather than your documents: separates what changed from what was verified, cuts invented confidence, leads with the action and keeps load-bearing caveats. Manually invoked and stays on until you say stop; a script can enable it in CLAUDE.md or AGENTS.md.

Neon's official plugin combining the Neon MCP and skills to manage serverless Postgres: projects and branches, object storage, Functions and the AI Gateway. Signs in to Neon via OAuth the first time you use the MCP.

Official Google Ads API assistant: ask in plain language, generate and validate GAQL queries, run them to export account data to CSV, and debug offline conversion uploads. Account-changing code is generated, not run. Needs a developer token, credentials file and Python 3.10+.

Wolfram's official agent tools: use the Wolfram Language and Wolfram|Alpha for symbolic and numeric math and scientific and statistical data, for teaching and research. The command runs the official Docker image with a free developer license; Wolfram 15+ users can install it in the app.

PostHog's official plugin with a built-in MCP and 30+ skills: query product analytics, feature flags, A/B experiments, dashboards and error tracking from chat, and optionally send Claude Code sessions to LLM Analytics. Needs OAuth sign-in with a PostHog account.