"Free servers available for testing purposes" matching MCP tools:

• generate_spf

  IntoDNS.ai DNS & Email Security Scanner

  Build an SPF (Sender Policy Framework) record — the DNS TXT record that lists which servers may send mail for a domain. Pass the senders as `mechanisms`: `include` for a provider's own SPF (Google Workspace is `_spf.google.com`, Microsoft 365 is `spf.protection.outlook.com`, SendGrid is `sendgrid.net`), `ip4`/`ip6` for your own servers, plus `useMx`/`useA` to authorise the domain's own MX or A records. The `policy` decides what receivers do with mail from anywhere else: 'fail' (-all, the production choice), 'softfail' (~all, for testing), 'neutral', or 'pass' (+all, which authorises the entire internet and should never be published). SPF is limited to ten DNS-triggering terms during recursive evaluation. This pure builder counts direct mechanisms; include and redirect targets can add nested lookups, so validate the published record with check_spf before treating the count as final. Returns the record, direct lookup count, whether that direct count or the 255-character limit is exceeded, plain-language warnings, and the DNS entry to publish. Use check_spf to resolve and validate a live record, and flatten_spf only when an existing record is over the limit. Nothing is looked up or stored — this is computation only.

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• check_headers

  ContrastAPI

  Validate HTTP security headers you provide (JSON): CSP, HSTS, X-Frame-Options, X-Content-Type-Options, Permissions-Policy, Referrer-Policy against best practices. Use to test header config before deployment or validate non-public servers; use scan_headers to fetch live. Free: 30/hr, Pro: 500/hr. By default header values are truncated to 500 chars; pass include='full' for the full raw value. Returns {total, by_severity, findings}. No external requests.

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• get_quota

  TollCalc MCP

  Check remaining free-tier quota for this MCP session. Without authentication, 10 free requests are available per session. Pass an API key via Authorization: Bearer <token> header for plan-based quota.

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• tech_fingerprint

  ContrastAPI

  Detect website technology stack: CMS, frameworks, CDN, analytics tools, web servers, languages (via HTTP headers + HTML analysis). Use for passive reconnaissance; for full audit use audit_domain. Free: 30/hr, Pro: 500/hr. Returns {technologies: [{name, category, confidence%, version}]}.

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• get_insider_activity

  Stocklake — AI Stock Intelligence

  Get AI-synthesized insider + institutional activity for a stock. Returns combined signal (BULLISH/BEARISH/NEUTRAL etc.), flag_score (8+=notable), confidence, per-source breakdown, and a human-readable summary. Data covers insider transactions (SEC Form 4) and institutional holdings. Pro tier only — AI pipeline cost attached. For informational purposes only. Not financial advice.

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• check_coverage

  ZoningVerdict

  Free coverage preflight for an address or municipality string. Returns whether ZoningVerdict covers it, available topics, pack version, and last-reviewed date. It does not identify a parcel's zoning district; use resolve_parcel_district only when the district determination is needed. Results are for information purposes only.

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• list_municipalities

  ZoningVerdict

  List the municipalities ZoningVerdict covers, with each pack's version and last-reviewed date. Coverage is reviewed summaries of public zoning ordinances, for information purposes only. Start here when you do not have a street address; with an address, start with resolve_parcel_district.

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• search_mcp_registry

  fresh-feeds — trending/new/changed MCP servers + x402 change-data API

  Search the continuously-maintained MCP server registry (deduped, quality-scored, refreshed every 30 min) by name/title/description. Free; returns up to 25 matching servers with score, status, remotes and packages. For the FULL corpus (~1500 servers) use get_mcp_registry_snapshot (paid, x402).

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• get_faq

  CalmActiva

  Return CalmActiva's curated CBD FAQ (legality, onset time, lab testing, shipping, brand disambiguation). Use for general CBD/brand questions before falling back to web search.

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• book_demo

  gethal.ai

  Submits a demo request. The prospect receives a confirmation email and must click the link in it before the request reaches a human at A Cloud Frontier. Use only when a real person has explicitly asked for a demo and provided their own working email address. Do NOT call this for testing, evaluation, or crawling purposes — automated and unconfirmable requests are rejected.

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• list_collections

  Skill of Skills

  The curated buyer-intent collections (e.g. mcp-servers, testing-qa, browser-automation). Use get_collection for the ranked tools inside one.

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• mcp_categories

  Find MCP - Agentage MCP Directory

  List the directory's available filter values - every category, language, and license, each with how many servers carry it. Call this BEFORE mcp_search when you intend to filter, so you pass exact, existing values for the type/category/language/license arguments instead of guessing. Takes no input. Read-only.

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• compute.models

  DPX — Institutional Cross-Border Settlement

  List all AI models available through DPX Compute. All models are free-tier (no token cost) — routed via OpenRouter. Returns model IDs, provider, capability strengths, context window, and speed tier. Use this before compute.route to understand what models are available and pick the right one for a task. Free.

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• create_port_monitor

  UptyBots

  Watch one TCP or UDP port on a host and report it up only when the service behind it actually answers. This is the type for game servers, databases, mail and anything else that speaks its own protocol rather than HTTP - Minecraft, Rust, CS2, FiveM, Postgres, Redis, SMTP. The port must be given as part of the url. Set protocol to UDP for game servers; most of them do not answer on TCP at all.

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• intelligence.subscription.delete

  DPX — Institutional Cross-Border Settlement

  Cancel an intelligence subscription by ID. Stops future webhook alerts for that subscription. The alert log is retained for audit purposes.

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• get_stock_news

  Stocklake — AI Stock Intelligence

  AI-analysed news for a stock, newest first. Only returns articles processed by our AI pipeline (sentiment, flag score, summary). - days: look-back window in days. Requesting more than your tier's cap is silently clamped down to it: 30 free/guest, 90 pro. - limit: max articles returned. The `limit=10` default is a Pro-tier-shaped value — on free/guest it's silently clamped down to that tier's cap (5), so a free caller passing no `limit` effectively gets 5, not 10. Requesting more than your tier's cap (5 free/guest, 50 pro) is likewise clamped down. - status: "ok" = articles returned | "empty" = no news in window - Per article: title, published_at, ai_sentiment, ai_flag_score (0-10), ai_summary (full text), ai_confidence (0-10) — Pro only, see below Free tier: up to 5 articles, title + published_at only (no AI fields), 30-day window. Pro tier: up to 50 articles with full AI fields, 90-day window. For informational purposes only. Not financial advice.

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• search

  vicp-registry

  Search VICP vaccine-injury cases by free text. Returns result ids for use with fetch. (Alias of search_cases for deep-research clients; prefer search_cases when structured filters are available.)

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• compute.models

  DPX — Institutional Cross-Border Settlement

  List all AI models available through DPX Compute. All models are free-tier (no token cost) — routed via OpenRouter. Returns model IDs, provider, capability strengths, context window, and speed tier. Use this before compute.route to understand what models are available and pick the right one for a task. Free.

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• list_capabilities

  agentstack-mcp

  Discovery: the three namespaces (sim_*, decide_*, calc_*), the cross-domain composite tools, the available ?profile= filters, and links to the standalone servers. Call this first to see everything AgentStack exposes. No parameters.

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• get_public_mcp_index

  Agentic Commerce Tools

  Return the Public MCP Server Index: a weekly-refreshed health, conformance and latency ranking of popular public (no-auth) remote MCP servers, scored 0-100 by the same live JSON-RPC handshake used by check_mcp_server. Includes per-server score, grade, latency, tool count, description quality and failing checks, plus aggregate stats (how many popular servers are auth-gated, average score and latency). Use it to pick a reliable public MCP server for a task, cite ecosystem statistics, or benchmark a server against the field. Free, no parameters. Curated by MCP Pulse (mcppulse.agiscorecard.com); on-demand scans of arbitrary servers at scale are available pay-per-call via x402 at https://x402.agiscorecard.com.

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