"Free Tools for Online Searches" matching MCP connectors:

Test-inbox API for email and SMS: create inboxes, long-poll messages, extract OTPs and links.

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).

Free platform to test MCP clients without installing anything. Create mock tools with dynamic templates, configurable delays, conditions (if/then), and response sequences. Supports JSON-RPC 2.0 over Streamable HTTP. Built-in text_echo and json_echo tools. Rate-limited tiers: anonymous (5 calls/min, 1 mock tool), registered (10 calls/min, 4 mock tools), premium (60 calls/min, unlimited). Zero setup — no install, no registration required. More info: https://www.testmcp.dev

Check that your AI is being logical. Free tool that mathematically catches contradictions in agent reasoning. No account needed. Also offers paid guardrails that converts natural language to formal verification proofs, that anyone can check succinctly.

Rule engine with built-in simulation. 55 MCP tools for complete business rule lifecycle management.

Promotion gate for AI agents: leakage audits, exact-statistics verdicts, and a live report card.

Hire a real human for real-world verification, product testing, AI output review, and errands.

Voice-powered bug reporting with 13 MCP tools. Record bugs by talking; let AI find and fix them.

Deterministic validation for AI-generated artifacts: JSON Schema, OpenAPI response, SQL syntax.

Generate realistic, FK-consistent synthetic test data for your databases from your AI assistant.

Generate deterministic placeholder image URLs and packs for docs, staging, testing, and AI agents.

Generate realistic relational test data — 156 field types, 22 locales, JSON/CSV/SQL, free previews.

Read-only MCP server for the OPERANT AI operating-agent calibration benchmark.

MCP server for the Fail Modes taxonomy — a knowledge base of AI system failure modes

Scan URLs for WCAG 2.1 violations, generate AI fixes, and produce VPAT 2.5 compliance reports.

Webhook relay for AI agents: keyless quickstart, event inspection, replay, mock payloads.

MCP-native AI evaluation: rubric audits, eval suites, and proof reports for AI/LLM output.

Read-only verifier for 25 ProofRelay MCP tools and non-confidential evidence bundles.

Adversarial behavioural-bias engine — audits your decisions for cognitive biases via your own AI.

Pay-per-call MCP server. Vetted human experts review AI-generated content (text, images, video, audio, social posts), audit reasoning chains, run prepublish safety checks, and gate high-stakes actions for human approval. 7 paid tools at $1.00 each plus 4 free tools (list_offerings, list_expert_profiles, get_result, verify_certificate). Payment via x402, USDC on Base mainnet. Approved outputs receive an on-chain Taste content certificate downstream agents verify before consuming.