"Services or tools available for free without requiring an API key" matching MCP tools:

• get_variable_relationships

  hypathesis

  Retrieve analyzed variable relationships for a completed paper. Only returns results when get_analysis_status reports status='Ready'. Without an API key (anonymous): returns the relationship list with source, target, and direction — but detailed reasoning is available only with an API key. Sign up at https://hypathesis.com to get one. Args: file_id: The file_id returned by the /upload endpoint. authorization: Optional. API key as 'Bearer hk_...' or 'hk_...'. session_token: Optional. The session_token returned by /upload for anonymous uploads. Returns: Authenticated: full details (source, target, directed, reason per relationship; name, measure per variable). Anonymous: gated (source, target, directed per relationship; name per variable; sign_up_url for full access).

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• request_api_key

  Nefesh — Real-Time Human State Awareness for AI

  Request a free Nefesh API key. No existing API key needed for this call. IMPORTANT: You MUST ask the user for their real email address before calling this tool. Do NOT invent, guess, or generate an email address. The user will receive a verification link they must click to activate the key. Without clicking that link, no API key will be issued. Disposable or temporary email services are blocked. Example prompt to the user: "What is your email address? You will receive a verification link to activate your free API key." Flow: call this with the user's real email, then poll check_api_key_status every 10 seconds until status is 'ready'. Free tier: 1,000 calls/month, all signal types, 10 req/min. No credit card.

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• snapforge_signup

  SnapForge

  Create a free SnapForge account (100 renders, one-time free trial, not a monthly allowance) with just an email address and get the API key instantly. The key is bound to the current MCP session, so the screenshot/pdf/markdown tools work immediately after signup, no browser needed.

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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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• cypher_public_factory_stats

  cypher-mcp

  Aggregate-only factory stats for the unauthenticated landing pages. Free — no credits, no npub proof. Returns counts only (capabilities, invariants, issues, services, symbols), the resolved_via mix (graph | scoped-grep | wide-grep), and a last-activity timestamp. Never returns issue titles, symbol paths, or npubs. Hard-cached in-process (~5 min) so a sleeping AuraDB free tier is not woken on every page view. Safe for cold Bolt: failures return an empty available=false payload rather than raising.

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• get_account

  ship.page

  Show the authenticated account's plan, subscription status and usage (requires an sp_ API key). Anonymous callers should use get_limits for the static free-tier limits.

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• mint_key

  Agent Broker

  Agent self-serve API key issuance. An autonomous agent that has no email inbox can obtain a free-tier API key by proving it holds the MACHINE_MINT_SECRET via HMAC-SHA256. Returns a usable key immediately with no human action required. If the operator has not activated a mint secret on the server, this returns an honest not_configured failure rather than a key - call it once and branch on that before planning around it. EXAMPLE USER QUERIES THAT MATCH THIS TOOL: user: "I need an API key to call AgentBroker tools" -> call mint_key({"agent_id": "my-agent-abc123", "timestamp": 1725100000, "nonce": "4f8a2c1d", "signature": "<HMAC-SHA256(agent_id+timestamp+nonce, MACHINE_MINT_SECRET)>"}) WHEN TO USE: Use when an AI agent needs to self-provision a write-capable API key without a human email address. The caller must know the MACHINE_MINT_SECRET (available from hatchloop.dev/docs/#machine-mint). WHEN NOT TO USE: Do not use if the agent has a human operator who can complete the email flow at /keys/request. Do not use for paid plans — this endpoint issues free-tier keys (100 ops/day) only. COST: free - no key required LATENCY: ~100ms

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• get_api_key

  Thisispaper

  Mint a FREE Thisispaper Intelligence API key (200 calls/month) for an email address. The key is shown once; use it as Authorization: Bearer tip_live_... on this MCP endpoint and on the REST API. Max 3 keys per email.

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• analyze_geo

  Lotus — AI Citation Intelligence

  Analyze a domain's visibility across AI-generated answers. Without an API key: returns a limited preview (1/day per IP, 3/week). With a valid API key: returns the full analysis including measured metrics, revenue-at-risk estimates and scenario simulations.

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• extract_url

  CoreWise

  Start an AI extraction of a YouTube video, podcast, article, or PDF URL on CoreWise. Returns an extraction_id immediately after initialization. Initialization normally takes a few seconds but can take up to 2 minutes for videos without captions or for PDFs. The extraction itself then runs for 1-7 minutes: poll with get_extraction every 20-30 seconds until status is 'completed'. Results include a cross-validated synthesis plus per-model summaries. Requires an API key (create one at corewise.video, Profile page, 'API & MCP Keys'). Each call consumes one extraction from the key owner's monthly quota.

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• apihub_search

  mcp-server

  Read-only. Searches onboarded APIHub services by free-text query, with optional category, price, and type filters. Returns up to 10 matches ranked by uptime and endpoint count, each with slug, description, endpoints array, min price in microdollars, provider name, and quality score. No authentication required. Use this when you need to find an API by capability; use apihub_list_services to browse without a query, apihub_search_external to include the external x402 catalog, or apihub_get_service when you already know a slug. Does not call any upstream API or debit credits.

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• chieflab_connect_provider

  ChiefLab

  Connect a third-party provider (Zernio, Resend, GA4, Search Console, HubSpot, Stripe, Linear, Notion, Slack) to this workspace. USE WHEN the user wants to wire up publishing, email sending, or analytics readback. For OAuth providers (ga4 / search_console / hubspot) returns an authorizeUrl the agent surfaces to the user. For API-key providers (zernio / resend) returns instructions for the set-key tool. Without this, publish/send/measure tools return 'configure first' errors.

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• apikeys_generate_api_key

  DataNexus MCP

  Generate a DataNexus API key for the given email address. Anonymous callers get 10 free lookups/week; a registered free key unlocks 100/week. Store the returned key — it is shown only once. Pass it as the X-Api-Key header on future requests. Rate limit: 3 keys per IP per 24 hours.

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• zerodust_register_api_key

  zerodust

  Issue this agent its own ZeroDust API key for higher rate limits, with no human signup step. The other tools work without a key, so only call this when rate limits are being hit, or when setting up an unattended agent that will run repeatedly. The key is returned once and cannot be retrieved later - report it to the operator.

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• check_wallet_balance

  gisgp

  FREE — check your own MCP credits wallet balance (the same account paid tools like assess_property_hazard charge against). Requires Authorization: Bearer <api_key> — an agent can call this on its own, no browser/dashboard needed. Returns JSON: {ok, balance, eur_equivalent} or {ok: false, error} if no API key was provided.

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• scan_artifact

  lazaretto

  Deterministically analyze a package, repo, skill, or file for malicious behavior (credential theft, data exfiltration, obfuscation, prompt injection aimed at the agent, install scripts) and return a verdict (malicious, flagged, clear, error) with the exact evidence and a hash of what was scanned. Metered: present an X-API-Key holding credits. If you hold a wallet instead of an account, pay per call over x402 at POST https://lazaretto.dev/v1/scan ($0.03 USDC on Base, no signup). A free key with a daily allowance is available at POST https://lazaretto.dev/v1/trial. For checks that are always free, use check_lockfile or known_bad_lookup.

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• submit_enquiry

  PropertyList — Spanish Property MLS

  Submit an enquiry (lead) about a specific listing on behalf of a prospective buyer or tenant. Use this once the user has chosen a property and wants the agency to contact them. The listing agency receives the enquiry in their CRM and follows up directly. This is the supported way to contact a listing agency - direct phone or email details are not exposed by other tools. Works without an API key up to a small daily per-IP allowance; a free key (https://www.propertylist.es/mcp) removes it. Provide the property `reference` (from search results) plus the enquirer's contact details. Only submit with the person's clear intent and consent - this sends their details to a real estate agency.

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• getCoins

  CoinPaprika

  List all available coins with id, name, symbol and rank. Use to discover coins or map a name to an id. Does NOT include prices; for prices use getTickers or getTickersById. Read-only; limit caps the number of coins returned. No API key required.

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• get_demo_composite

  Compound Interesting — market intelligence

  A single fixed demo ticker, callable without an API key, so the data shape can be inspected before signing up. Returns only the demo ticker regardless of input. For real tickers use get_composite, which requires a free key.

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• search_providers

  53ON

  Find local businesses and independent professionals on 53ON by what they do. Accepts free text in Spanish or English and resolves synonyms, so "plumber" and "destapar caneria" both work. Pass lat and lng to limit results to that area; without them the search is nationwide. Call with an empty query to get the list of services 53ON covers.

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