"MCP servers that work without API keys" matching MCP servers:

Enables your own ChatGPT to build and manage a collaborative work board—dashboards, categories, datasets, monitors, and policies—through typed WebMCP tools, with human approval, audit trails, and guardrails enforced on every action.

Generate annotated post-trade candlestick review-chart PNGs from broker or exchange fills. Includes capability checks, no-charge preflight validation, and chart rendering; no signals or order execution.

AI-powered Fantasy Premier League assistant — scored captain picks, transfer suggestions, differentials, fixture outlook, price predictions, live points, and a full manager hub that auto-detects your squad, bank balance, and free transfers.

Exposes read-only tools for searching players, fetching profiles, live matches, match history, stats, leaderboards, heroes, team-ups, insights, matches, and factions from Marvel Rivals public data. It also returns an MCP-UI player dashboard rendering rank, competitive record, live match rosters, hero win rates, and recent match form, over local stdio or Streamable HTTP.

Analyze survey data (.sav, .csv, .xlsx) through Claude — crosstabs with significance testing, ANOVA, correlation, gap analysis, and publication-ready Excel exports. Upload once, analyze unlimited.

Enables agents to compile a semantic chart description (data, semantic types, chart intent) into native specs for five charting libraries and headlessly render three of them to SVG or PNG, delivered inline or as signed, expiring artifact URLs. It also exposes tools for validating charts, listing chart types and themes, plus resources and prompts that supply chart-authoring and theming conventions.

Enables rendering, validation, formatting, and inspection of D2 diagrams via the Model Context Protocol, using WASM for rendering without requiring the d2 binary.

A read-only, cross-platform visualization layer for Cortex that renders memory, sessions, and code into six live reading angles (graph galaxy, 3D anatomical brain, execution trace, consolidation board, knowledge browser, and wiki) without ever writing a memory.

Enables LLMs to generate visual summary reports from CSV datasets using MCP Resources, Tools, and Prompts, without exposing raw data to the model.

MCP server that lets agents create and update persistent concept maps via the NodeLand API, returning shareable URLs for humans to view, embed, and keep editing.

A Model Context Protocol server that renders Apache ECharts options to SVG, enabling AI agents to generate deterministic charts server-side without a browser.

Enables AI assistants to load vibration signals, detect machinery faults with spectral evidence, assess severity against ISO 20816-3, and generate diagnostic reports locally without guessing.

MCP server that enables natural-language-driven, headless HEC-RAS modeling, letting agents inspect, edit, run, compare, and plot 1D/2D hydraulic models without the GUI.

A free MCP server that renders bar, line, and area charts from structured data into clean, hand-designed SVG. No API key or payment needed, with colorblind-safe palettes and light/dark theme support.

Enables any MCP client to evaluate Wolfram Language code in a persistent local Mathematica or Wolfram Engine kernel, export results to common file formats, and inspect or manage kernel status without cloud APIs, API keys, or runtime dependencies.

A graph layout server that computes node coordinates and edge paths from structure using elkjs, enabling agents to offload layout calculations without rendering.

Provides Vietnamese stock market data and technical analysis tools via VNDIRECT's public API, including OHLC candles, fundamentals, chart rendering, MACD divergence detection, and market structure analysis. Enables MCP clients like Claude Code to fetch and analyze stock data without API keys.

MCP server that automates the publishing and validation of Tableau workbooks and data sources on Tableau Server or Tableau Cloud, enabling an AI agent to discover, build, validate, and publish content without human intervention.

An MCP server that turns chart requests into permanent, hosted Image-Charts URLs, enabling agents to generate charts that render anywhere without client-side libraries.

An MCP server for the Xe Currency Data API that brings live FX rates, historical analysis, and quant-flavored tools into AI tools, working out of the box with zero credentials via Frankfurter/ECB data.