"An overview of knowledge graphs" matching MCP connectors:
GET /v1/connectors – MCP directory API referenceMatching Connector Tools:
Check an A2A agent before you delegate, or an MCP server's measured conduct. Free, no key.
12 free MCP tools for local validation of emails, URLs, IP addresses, IBANs, dates, UUIDs, JSON and other structured inputs. No API key or external verification service required.
Disposable test inboxes for agents: create an address, then wait for its code or link.
Disposable, receive-only email inboxes for AI agents. Create an address, wait for the verification email, and get the one-time code or magic link back as structured fields. Long-polling wait_for_email with sender and subject filters, attachments, sanitised HTML, and restore for later password resets. OAuth 2.1, hosted in the EU, cannot send email.
Ensemble testing of web pages for accessibility, usability, and web standards
Free AI visibility check: can AI crawlers read a site, and do ChatGPT, Gemini, Perplexity cite it?
Benchmark your own prompt on 100+ models with real API calls, then choose the winner by accuracy, cost, speed, or any mix of those.
Independent schema and rule check of AI agent output before you pay. Signed attestation and receipt.
Runs an eight-stage isolation test against your staging Supabase and issues a signed attestation. Needs a RowAttest API key: Authorization: Bearer rak_... (create one on the API keys page in the app).
Assign Linear, Jira or GitHub issues to an AI coding agent team that plans, builds, reviews, tests.
Configure mobile bug reporting and investigate saved bug reports with your coding assistant. Manage apps and reporter settings, get Android/iOS/React Native setup guidance, and read report metadata, screenshots and logs. OAuth with an existing BugScreen account and workspace. Docs: https://www.bugscreen.app/docs/mcp
Verify an artifact an AI agent produced — schema, emptiness, provenance and mandate authority — before you accept the work or pay for it. Ed25519-signed and verifiable without this service; 20 checks a day free, then 0.005 USDC per call over x402.
Disposable email inboxes for AI agents: create an address, wait for mail, read OTP codes and links.
Risk-scan a diff, flag AI-generated-code tells, find secrets. 5 of 7 tools need no account.
Diagnose why an AI agent failed and get the verified fix instantly. Free, no token.
Validate CSV columns, find duplicates and invalid values, and clean files with explicit rules. Row-level reports, no stored files. Run the fixed free sample without a key. Custom CSV: EUR 9 for 100 operations, valid 90 days, no subscription. Setup: https://import-check-production.up.railway.app/docs/
Run, debug, and triage tests from your IDE using natural language, no dashboard switching, no manual data transfers. The TestMu AI (formerly LambdaTest) MCP Server is a single remote server exposing four tool suites: HyperExecute — analyze your project, generate YAML configs and test runner commands, then monitor jobs and sessions. Automation — pull a TestID's details plus command, network, and console logs into one chat for instant root-cause analysis. Includes mobile app upload. SmartUI — explain pixel, layout, DOM, and perceptual changes in a visual regression run, with context-aware React/HTML/CSS fixes. Accessibility — audit any public URL or a local React app against WCAG and get ready-to-apply remediation steps. Connects over https://mcp.lambdatest.com/mcp using OAuth 2.1 — no API keys in your config. One-click install in Cursor; works with Claude, GitHub Copilot, Cline, and any MCP client. Tests execute on the TestMu AI cloud: 3,000+ browsers and 10,000+ real devices.
Evidence-gated task verification for AI agents. Decompose goals into acceptance criteria, attach proof (screenshot, curl, file), independent LLM judge accepts or rejects. 24 tools. Hosted remote MCP (streamable-http, OAuth 2.1 + DCR).
An open-source benchmark of how well LLMs solve nonogram puzzles, from 5x5 to 20x20.
UI Verify is visual regression testing built for coding agents. Connect the MCP server and your agent (Claude Code, Cursor, Codex) pulls a pull request's UI changes into the conversation, views each visual diff, reads the AI judge's verdict of regression vs intended change, and accepts the intended baselines - all over MCP.
