"How to check Bitcoin (BTC) balance" matching MCP servers:

Retired. This MCP wrapper is no longer maintained. Check is now a Claude Code hook: npx @golproductions/check@latest --install. 120 free messages a day. Details: golproductions.com/check

Provides authoritative open source license answers: SPDX identification, copyleft classification, and compatibility checks of dependencies against your project's license.

Lets AI agents check whether an EVM wallet address carries an EIP-7702 delegation across eight chains (Ethereum, Base, BNB Chain, Arbitrum, OP, Polygon, Gnosis, Unichain) and learn how to obtain a deeper paid report with delegate bytecode heuristics and risk levels. Read-only, never touching private keys or seed phrases.

Read-only Supabase RLS check: explains in Arabic which tables anyone can read or change. No keys.

Enables AI agents and scripts to rug-check any token on Base, Ethereum, Arbitrum, Optimism, Polygon, or Solana, returning a 0-100 risk score with plain-language reasons and a fingerprint for detecting changes on later checks. It also reports market data and supports automatic $0.01 USDC payments via x402.

Explains cron expressions in plain English, checks them for errors and gotchas, lists next run times in any time zone, and converts between Unix cron, GitHub Actions, Kubernetes, AWS EventBridge, Quartz and Spring dialects.

Enables agents to validate and normalize phone numbers, email addresses, and postal addresses with production-grade, country-specific rules, including formatting, typo detection, and checks for disposable domains or fictional numbers.

Runs SQL statements in memory against real PostgreSQL 18 and SQLite 3.49 engines after loading your schema and sample rows, returning each statement's own verdict: errors with line, column, and hints, constraint violations, or the resulting rows. It also compares both dialects to expose portability differences, all with no database server, network, or API key.

Runs a regular expression on real engines — JavaScript (V8), Python (CPython re), PCRE2 and RE2 — reporting each engine's own compile errors with positions, every match with its groups and named groups, replacement results, and where the engines disagree. It also detects catastrophic backtracking (ReDoS), naming the at-risk part of the pattern, generating an attack string, and timing how long each engine actually takes on it.

Enables reviewing GitHub Actions workflows for outdated actions, deprecated Node runtimes, retired runners, deprecated commands, and security risks, with file, line, and fix for each finding.

Local-only GitHub Actions and CI maintenance scanner for AI-built apps. Exposes scan, explanation, and fix-planning tools to MCP clients; modifies nothing and makes no outbound requests by default.

Enables verifying citations in reference lists and BibTeX by detecting fabricated or mismatched references and retractions, and returning corrected BibTeX.

Enables agents to validate JSON, JSONC, YAML, and TOML configuration files against official SchemaStore schemas, pinpointing errors and likely key misspellings, and to look up schema-backed setting details.

Enables agents and users to validate Kubernetes manifests (YAML/JSON, multi-document) against the API of a chosen Kubernetes version without needing a cluster. It reports removed or deprecated APIs with replacements, unknown or misspelt fields, misconfigurations the API server would reject, Pod Security Standard violations, and common risks, each with file, line, and fix.

Enables agents to validate Dockerfiles for build-breaking syntax errors, risky patterns like root users and secrets in ENV/ARG, and cache-order problems, returning every finding with its line and a fix. It also verifies referenced container images against public registries, reporting tag existence, digests to pin, supported platforms, last rebuild time, and end-of-life status with an upgrade tag.

Scores any remote MCP server for readiness across the Claude Directory, ChatGPT Apps, Gemini Connected Apps, and MCP Registry, returning a 0–100 score, A–F grade, per-store status, failing checks, and one-line fixes. Also provides report links, badges, and explanations of each check.

Enables AI coding assistants to scan an iOS, Android, Flutter, React Native or Expo project for App Store and Google Play rejection risks, returning deterministic findings that cite the guideline section, link to the official Apple or Google page and explain how to fix each problem. Nothing leaves the machine and no AI is used in the checks.

Enables AI coding agents to inspect GitHub repositories and shell commands for download-and-execute payloads, obfuscation, typosquatted dependencies, autorun hooks, and fake-star signals before following or running them.

Enables agents to convert Markdown into WhatsApp-compatible formatting, including styled text, lists, and tables that fit a phone's monospace width.

Enables users and AI agents to verify whether a crypto recipient address is an address-poisoning lookalike or has an invalid EIP-55 checksum before sending funds, and provides access to an on-chain history scan for suspicious transfers.

Enables checking whether a crypto link is a phishing lookalike of a wallet, exchange or dapp by comparing it against official domains and flagging lookalike characters, typosquats, punycode and bait words, fully offline. An optional paid full check adds domain registration age, DNS, redirect tracing and a page scan for seed-phrase prompts and drainer code.

Enables MCP clients to turn Make blueprints and Zapier exports into n8n workflow files, with a per-step report of what converted, what to review, and what must be finished by hand. Also lists zaps, explains how individual steps are handled, checks workflow files for broken links or placeholders, and can upload the result to an n8n instance as an inactive workflow.

Enables AI assistants to convert CSS-animated SVGs into videos (MP4/WebM/MKV/MOV) and animated images (aPNG/GIF) with frame-accurate rendering and transparency support.

Free open-source CLI and read-only MCP tool from Advisors AI (advisorsai.ai): give it one public URL and it lists which machine-readable basics are present or missing (title, meta description, structured data, one h1, canonical, robots policy for AI crawlers, llms.txt, sitemap). No API key, no account, nothing stored.

Searches US product recalls across CPSC, FDA, and NHTSA in one call, matching by name, brand, model number, UPC, or VIN with confidence scoring.

Enables AI agents to validate a Japanese qualified invoice against the six required items, reduced-rate markings, per-rate totals, and once-per-invoice-per-rate tax rounding, while flagging the common line-by-line rounding mistake, and to normalize and verify T + 13-digit registration numbers. Read-only tools also compute expected consumption tax for a given amount, rate, price basis, and rounding method.

Provides a check_links tool that lets AI apps verify up to 200 URLs at once, returning status codes, redirect chains, final URLs, and connection errors.

Reads a small-business website like a customer would and shows where they get stuck. Every AI answer has to quote the page, and the server checks the quote before it counts.

MCP server that checks a website's AI-search (GEO) readiness: robots.txt access for 16 AI crawlers (GPTBot, OAI-SearchBot, PerplexityBot, ClaudeBot, Google-Extended, Bingbot...), JSON-LD schema, llms.txt, sitemap and basic SEO tags. Python, stdio, MIT.

Compares a project's .env file against its .env.example template to surface missing, extra, and empty keys, flag empty required variables, and produce paste-safe key inventories for tickets or sharing. Runs entirely on local files with every value redacted, so secrets are never echoed or uploaded.