Find an agent your AI can call

Small, reliable utility APIs for AI agents. Paid endpoints charge per call in USDC over the x402 protocol (HTTP 402 flow) - no accounts, no API keys. Free endpoints are open.

Payment-gated Twitter/X user and tweet lookup API. Pay per request in USDC on Base via x402.

Takes two state documents — target (what the twin should look like) and observed (what was measured) — and returns a leaf-by-leaf comparison. Every leaf path carries one of five states: in_tolerance, out_of_tolerance, missing_in_observed,… (3 paid endpoints on agent.halowerk.com.)

Canonical paid interface backed by Evidence Engine V2. Submit a natural-language query; vertical is an optional routing hint. Explicit two-subject text comparisons return independently attributed evidence, coverage, provenance, limitations…

Calculates each group positive-outcome rate, compares it with an explicit or automatically selected reference group, and reports rate differences and selection-rate ratios. Aggregate disparity metrics do not establish discrimination, fairn… (10 paid endpoints on aialign.halowerk.com.)

q verwendet echtes SQLite FTS5, zusätzlich stehen Namespace und Tagfilter bereit. Die verifizierte Zahleradresse ist der Eigentümer; Ergebnisse und gespeicherte Daten sind strikt auf diesen Zahler begrenzt. (6 paid endpoints on intel.halowerk.com.)

Add a new memory. This method is called every time the user informs anything about themselves, their preferences, or anything that has any relevant information which can be useful in the future conversation. This can also be called when th…

Call this when an agent needs current significant global disaster events — e.g. before routing logistics or assessing exposure. Returns ALL matching normalized GDACS multi-hazard alerts (earthquake, cyclone, flood, volcano, drought, wildfi… (3 paid endpoints on wailand.tailf99551.ts.net.)

Pay-per-use browser sessions with crypto. No API keys, no accounts -- just pay and connect via x402 or MPP.

Skip the groundwork with our AI-ready Web Search APIs, delivering advanced search capabilities to power your next product.

150+ chains, in any AI client. Install the Allium MCP server, skill, or CLI in one command — or skip the API key entirely and pay per query in USDC.

Keyword news search across web news engines (Bing/DuckDuckGo/Yahoo via ddgs). Returns dated headlines with title/url/snippet/source/image + freshness/region/safesearch filters.

Search onchain DEX pools and token, by contract address, name, or token symbol.

By-the-minute Hyperliquid market-data archive, paid per request via x402 (no signup, no API key). Serves history Hyperliquid exposes no endpoint for (open interest and funding over time, HIP-3 perps (equities, commodities, FX; e.g. xyz:AAPL, xyz:SP500) and HIP-4 outcome markets), alongside OHLCV candles, raw trades, forced liquidations, and a survivorship-bias-free listings/delistings log. Free discovery endpoints; paid data answers HTTP 402 until you pay sub-cent USDC on Base or Hyperliquid HyperCore.

Pay-per-request Tavily web search over the x402 protocol.

Paint one pixel on 21millionpixels.art, a shared 21,000,000-pixel canvas. Reads are free; paid pixels skip the human cooldown. (2 paid endpoints on 21millionpixels.art.)

Generate UUID v4/v5/v7, ULID, or NanoID (single or batch), or parse/validate an existing id and extract its embedded timestamp. (23 paid endpoints on api.24klabs.ai.)

Latest daily stock quote for a US-listed ticker. Returns the most recent completed trading session: open, high, low, close, volume, VWAP, and trade count, plus the change and percent change versus the prior session, and company reference d… (108 paid endpoints on 2s.io.)

Structural address check: country, street, city, and postal pattern for common countries (TR, US, GB, DE, FR, NL, …). Returns a normalised single-line form and named issues. Not proof of deliverability. (111 paid endpoints on 402.com.tr.)

Cron for AI agents: signed HTTP deliveries on a cron expression. ENTRY pack: 20 delivery credits for $0.02 ($0.001/delivery). Same service, best rate $0.0005/delivery at https://402cron.com/buy/starter. Ladder: 20/$0.02, 2000/$1, 50000/$25… (2 paid endpoints on 402cron.com.)

Website uptime and change check: is this URL up right now, and has the page changed? Fetches the URL and returns the HTTP status, Last-Modified and ETag headers, a SHA-256 fingerprint of the content, and whether it changed versus a hash yo… (5 paid endpoints on 402oracle.com.)

Publish a listing on 402post, the classifieds board for AI agents: $0.03 USDC for 30 days. POST the listing as JSON; a bad one gets a free 422 with every error, a good one gets this 402. Dry run: POST /v1/posts/validate. Batch: {"listings"… (3 paid endpoints on 402post.com.)

Payment integration check for 0.001 USDC; no external data lookup. Returns time, rail, network mode and free/paid capabilities. HTTP payment options can include Base, Polygon, Arbitrum and XDC; the challenge lists currently available netwo… (3 paid endpoints on api.402rates.com.)

Convert a time between any two IANA time zones (DST-aware). Pay-per-call in USDC on Base.

Official daily foreign exchange reference rates from the European Central Bank (~30 currencies vs EUR, published each business day around 16:00 CET), rebased on request to any listed currency via EUR cross-rates and filtered to a requested… (3 paid endpoints on 4yearcycle.com.)

Get real-time spot price and market data for a cryptocurrency

Signed time-bounded witness of an agent-carried payload digest; the payload stays with the agent (3 paid endpoints on 767-2676.com.)

Convert a non-negative weight or mass value between common units. Use this deterministic endpoint when an agent needs a precise unit conversion. (2 paid endpoints on 87-106-119-237.sslip.io.)

Read one public webpage URL and return clean, LLM-ready Markdown or plain text. Designed for AI agents that need webpage contents, RAG context, research or summarization. (2 paid endpoints on api.aarn.space.)

Fetch a verified contract's ABI and metadata by address, keylessly, from Sourcify. Returns the ABI plus a summarized list of function and event signatures, the contract name and compiler, and proxy detection (is_proxy + implementation addr…