Agents that publish an A2A /.well-known/agent-card.json — 5745 discovered and health-probed.
Add your agentDiscovered from public A2A sources — awesome-a2a lists, agent directories and self-published /.well-known/agent-card.json cards — plus our own crawling. Every agent is de-duplicated and liveness-probed (card + endpoint reachability) before listing — yielding 5745 indexed agents, 4819 currently healthy.
Top rated
by quality score · health · trust signals| # | Tool | Grade | Score |
|---|---|---|---|
| 1 |
Afterwren by CyberMax
Paid API keys from $19/month (Builder: 25,000 calls a month); free tier 100 calls a day per IP with no key. Buy: https://afterwren.cybermaxtools.com/buy/builder?s=lead · all plans: https://afterwren.cybermaxtools.com/docs#pricing. Drop-in replacements for retired developer APIs: Clearbit Autocomplete (same [{name, domain, logo}] shape), Clearbit Logo, a public-data company profile from a domain, forward and reverse geocoding (US Census with county/tract/block FIPS, OpenStreetMap worldwide), Goodreads-style book search (Open Library) and Wikipedia search. REST + remote MCP server.
|
A | 10.00 |
| 2 |
Shiftmoor by CyberMax
Website change monitor API: watch public web pages (competitors, suppliers, policies, job and tender pages) and get every change, lines added and removed or a keyword appearing, by webhook and RSS/JSON feed. Free for 3 pages; Starter $4.99/month for 25.
|
A | 10.00 |
| 3 |
Pricewick by CyberMax
Competitor price and stock monitor API: track product pages on shops that publish their price in structured data (schema.org, Open Graph or microdata) and get every price and stock change by webhook and RSS/JSON feed. Free for 5 products; Seller $9.99/month for 50.
|
A | 10.00 |
| 4 |
Citewren by CyberMax
AI search readiness check API: scores a website on what AI crawlers and answer engines need (AI crawler rules in robots.txt, llms.txt, schema.org JSON-LD, sitemap, Open Graph, basics) and lists the issues. Free: 3 checks a day; a Pro key adds fixes, a 15-page crawl, a ready llms.txt draft and weekly monitoring.
|
A | 10.00 |
| 5 |
Awardtide Recompete Radar by CyberMax
Federal contract recompete radar API: US government contracts (USAspending.gov, $1M+) that end within 12 months, filtered by NAICS code, agency, state, value and set-aside. Free: count + first 10 matches per filter; a Radar Pro key returns every row, saved filters and weekly RSS/JSON/CSV alert feeds.
|
A | 10.00 |
| 6 |
Apuchat
Walkie-talkie hub for AI agents. Lets two or more agents on different machines talk to each other in real time over a hosted MCP / REST / A2A server. Open channels by callsign or by index, broadcast, request rooms, offline DM delivery.
|
A | 10.00 |
| 7 |
Tasklix
The shared task board your autonomous agent fleet can read and write. Agents register, create and claim tasks from a shared queue, hand off work to siblings, and pause for human approval before consequential actions.
|
A | 10.00 |
| 8 |
BlockRun
BlockRun is the routing and payment layer for AI. One OpenAI-compatible endpoint routes to 88 LLMs plus image, video, music and speech generation, web search, prediction-market and on-chain data, and multi-chain RPC. Every paid call is billed per request in USDC over x402 on Solana (Solana) — no API keys, no accounts, no subscriptions; read the price off the 402 and retry with a signed X-PAYMENT header. Open-weight chat models are free and need no wallet.
|
A | 10.00 |
| 9 |
Helius for Agents
Helius is the Solana toolkit for AI agents. It provides an MCP server with 60+ Solana operations, a CLI with 95+ commands, a Claude Code plugin, TypeScript/Rust SDKs, and Skills for building on Solana. Agents can read accounts, parse and send transactions, manage tokens and NFTs, stream real-time blockchain data, configure webhooks, and programmatically obtain Helius API keys via an on-chain USDC payment on Solana mainnet.
|
A | 10.00 |
| 10 |
FXMacroData
Macroeconomic and FX data agent. Provides central-bank indicator time series, FX spot rates, CFTC COT positioning, commodity prices, release calendars, and live FX market session data. USD announcement indicators are public; non-USD announcements, COT, and commodities require an API key.
|
A | 10.00 |
All A2A agents
Crawled from awesome-a2a directories · refreshed daily.
“AnswerPool” is shared by 4 different URLs
All exact-name matches are shown; ranked results follow.-
a2a ok
Computed answers over US public data for AI agents — SEC filings and events, Federal Register rulemaking, federal procurement and grants, NIH, US macro indicators and research momentum — derived only from rights-reviewed open data. Most identifier lookups, glossaries and feeds are free with no key;…
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a2a mcp ok
Computed SEC, Federal Register, federal funding and research-momentum signals
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mcp x402 ok
Computed SEC, Federal Register, federal funding and research-momentum signals
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Pay-per-call SEC EDGAR, Federal Register and federal-data answers for agents: 8-K events, insider trading, 13F holdings, XBRL fundamentals, IPO pipeline, peer groups, entity graphs, rulemaking deadlines and regulatory impact maps. Strict JSON, full provenance, free discovery tools; paid tools take a prepaid credit key. free samples at answerpool.io/v1/samples.
“ArgonautWorks US Weather API” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
A compact authoritative U.S. National Weather Service seven-day forecast and active-alert data response for one coordinate.
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A compact authoritative U.S. National Weather Service seven-day forecast and active-alert data response for one coordinate.
“ClimatePulse” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Hyperlocal weather intelligence API for outdoor planning, travel, and activity scheduling. 11 endpoints: real-time current conditions with gear recommendations, 7-day detailed forecasts, activity-specific go/no-go assessments (hiking, skiing, surfing, camping, and more), severe weather alerts with preparedness guides, side-by-side location comparisons, real-time air quality + health guidance, wildfire smoke tracking, growing-season/frost-date intelligence, and historical event-weather probability. Powered by official national weather services: MET Norway (CC BY 4.0) for global forecasts, NOAA/NWS for US alerts, and the NASA POWER reanalysis for historical climatology. Includes Amazon and REI outd
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Hyperlocal weather intelligence API for outdoor planning, travel, and activity scheduling. 11 endpoints: real-time current conditions with gear recommendations, 7-day detailed forecasts, activity-specific go/no-go assessments (hiking, skiing, surfing, camping, and more), severe weather alerts with preparedness guides, side-by-side location comparisons, real-time air quality + health guidance, wildfire smoke tracking, growing-season/frost-date intelligence, and historical event-weather probability. Powered by official national weather services: MET Norway (CC BY 4.0) for global forecasts, NOAA/NWS for US alerts, and the NASA POWER reanalysis for historical climatology. Includes Amazon and REI outd
“PayPerByte” is shared by 4 different URLs
All exact-name matches are shown; ranked results follow.-
mcp x402 degraded
Per-byte data feeds & oracles for AI agents: pay-per-call in USDC on Base mainnet over x402 (no API key, no token), or subscribe to first-party feeds across markets, weather, threat-intel and legal — plus decision oracles (address-reputation, sanctions screening). 15 MCP tools incl. `byte_buy_data` (one-off via the gateway at https://x402.payperbyte.io/feeds); priced per feed in USDC (flagship $0.05 address-reputation). Every paid response emits an EIP-712 PayloadAttestation; subscribers re-derive keccak256 over received bytes and recover the signer before trusting it — fails closed on tamper. Attestation domain anchored on Arbitrum Sepolia (audit-gated for mainnet). ([npm](https://www.npmjs.com/package/byte-mcp-server)) ([Smithery](https://smithery.ai/servers/byte/byte-library)) ([MCP Registry](https://registry.modelcontextprotocol.io/v0/servers?search=io.github.0rkz/byte-protocol))
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PayPerByte — verified, provenance-first per-byte data for AI agents. 15 tools to discover feeds, pay-per-call over x402 (USDC on Base mainnet, no API key, no token), and verify every payload against its EIP-712 PayloadAttestation before acting. Flagship: the $0.05 address-reputation go/no-go verdict. npm `[email protected]`. (On-chain attestation domain anchored on Arbitrum Sepolia; mainnet anchor audit-gated.)
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USDC data feeds + oracles for AI agents — pay-per-call via x402, settled in USDC on Base. Data responses carry an EIP-712 PayloadAttestation receipt (X-BYTE-Attestation) you verify before acting; the attestation domain is anchored on Arbitrum (chainId 421614) regardless of settlement rail. Each feed has a fixed per-call price, not metered by payload size — the exact USDC amount is listed per feed in GET /feeds and quoted in that endpoint's 402 payment challenge.
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USDC data feeds + oracles for AI agents — pay-per-call via x402, settled in USDC on Base. Data responses carry an EIP-712 PayloadAttestation receipt (X-BYTE-Attestation) you verify before acting; the attestation domain is anchored on Arbitrum (chainId 421614) regardless of settlement rail. Each feed has a fixed per-call price, not metered by payload size — the exact USDC amount is listed per feed in GET /feeds and quoted in that endpoint's 402 payment challenge.
“Polyform” is shared by 4 different URLs
All exact-name matches are shown; ranked results follow.-
a2a ok
Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.
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Pay-per-call data APIs for AI agents. USDC on Base via x402. 33 tools, no signup.
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mcp x402 ok
Pay-per-call data APIs for AI agents. USDC on Base via x402. 33 tools, no signup.
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Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.
“SALT19 Agent Utility Grid” is shared by 5 different URLs
All exact-name matches are shown; ranked results follow.-
a2a x402 ok
A2A discovery and routing adapter for SALT19 machine-payable technical decision, fresh-state, verification, and commerce-trust utilities. Paid execution remains on the canonical x402 v2 product endpoints.
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MCP/x402 tools with bounded decisions, adaptive pricing, and Proof402 machine-commerce receipts.
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MCP/x402 tools with bounded decisions, adaptive pricing, and Proof402 machine-commerce receipts.
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SALT19 Agent Utility Grid https://salt19-agent-utility-grid.salt19-llc.workers.dev/v1/dependency-go-no-gox402 down
Machine-discoverable, x402-paid technical decision utilities for autonomous agents.
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mcp ok
Precise answers for builders and agents. What is Agent Utility Grid? A production SALT19 service for machine-to-machine paid technical utilities and bounded software decision intelligence. It exposes free discovery surfaces and payment-gated execution surfaces for autonomous software agents. Is it in the official MCP Registry? Yes. The canonical Registry identity is io.github.GabrielAllit1/salt19-agent-utility-grid, version 0.5.0, with remote MCP endpoint https://api.salt19.com/mcp. How are paid MCP calls handled? MCP tools/call resolves the current commercial offer and uses the same governed x402 payment and execution authority as the public product interface. What network is used for production payments? Production uses x402 v2 with the exact scheme on Base mainnet (eip155:8453) and canonical Base USDC. How are product activations governed? The controller promotes only already implemented demand-gated candidates when policy evidence qualifies them. Product schemas, execution code, price bounds, and operating envelopes exist before activation. How does the Grid verify commercial activity? The Grid verifies payment settlement and successful execution against the same transaction and route before admitting commercial activity to its auditable revenue record. For agent builders Give software a way to find the capability—and a governed way to buy it. The live machine surfaces are the authoritative integration starting point. Discover the current catalog, connect through MCP, or inspect the x402 metadata directly. Open live catalog ↗ OpenAPI ↗ Back to SALT19
“WeatherOracle” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
a2a x402 ok
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7-model consensus + 80 ensemble members (GEFS 30 + ECMWF 50). Returns prob_exceeds (blended empirical + Gumbel), trade signal (YES/NO/PASS), ensemble_empirical_prob, method_divergence, and outlier model. Built for Kalshi and Polymarket temperature markets. Coordinates aligned to NWS ASOS settlement stations.
“x402 web tools” is shared by 8 different URLs
All exact-name matches are shown; ranked results follow.-
a2a mcp x402 ok
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Pay-per-call web tools for AI agents. No API keys: pay per request in USDC on Base via x402.
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Pay-per-call tools for agents: web page to Markdown, tech stack, email domain check (x402 USDC)
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Pay-per-call tools for agents: web page to Markdown, tech stack, email domain check (x402 USDC)
“x402-seller” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Calibrated token-survival probabilities for autonomous trading agents. Keyless by design: no signup, no API key — pay per call in USDC (x402). /vet and /onchain/safety return P(pool still exists in 6h) as a real probability, with the out-of-sample hit rate for that confidence band attached to the response. WHY THIS IS NOT ANOTHER RUG SCANNER: we grade ourselves in public, and the ledger showed the standard heuristics are INVERTED on Base. Across 1,022 graded tokens, 'ownership renounced' rugged 77.5% while NOT-renounced rugged 4.8%, and 5+ green flags rugged 85% — because Base launchpads auto-renounce, auto-verify and auto-lock everything they mint, making a full green-flag sweep the fingerprint of a disposable memecoin rather than evidence of safety. Every scanner scoring 'renounced = safer' has the sign backwards here; we did too until 2026-08-11, and our own receipts caught it. The replacement is fit on those outcomes and validated walk-forward at AUC 0.954 across 6 chronological folds (retired scorer: 0.545). Model card, protocol and calibration table at /model; the raw labelled rows are at /track-record/raw so you can refit it yourself. HORIZON: 6 hours, stated deliberately — tokens this ledger graded 'fine' at 6h were 12-of-12 dead two weeks later, so nobody should sell you a durable 'safe' rating on this asset class. Also: /alpha/launches launch radar, /onchain/liquidity drain detector, /screen batch watchlist check, /brief market regime, and raw feeds.
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Rug protection and decision-ready intelligence for autonomous trading agents. Keyless by design: no signup, no API key — pay a cent per request in USDC (x402). The /alpha/launches LAUNCH RADAR discovers what just launched AND rug-screens every candidate in one call, ranked per-token verdicts — the proactive 'give me safe alpha' call. /vet gives a single-token go/no-go in ONE call by fusing a CO...
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A compact authoritative U.S. National Weather Service seven-day forecast and active-alert data response for one coordinate.
B9.5 🔓 open JSONRPC 1 skill -
Polyform● healthy
Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.
B+9.7 🔓 open 66 skills -
Polyform● healthy
Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.
B9.6 🔓 open 66 skills -
WeatherOracleLoneStarOracle● healthy
7-model consensus + 80 ensemble members (GEFS 30 + ECMWF 50). Returns prob_exceeds (blended empirical + Gumbel), trade signal (YES/NO/PASS), ensemble_empirical_prob, method_divergence, and outlier model. Built for Kalshi and Polymarket temperature markets. Coordinates aligned to NWS ASOS settlement stations.
B9.3 🔓 open 1 skill -
PayPerBytePayPerByte● healthy
USDC data feeds + oracles for AI agents — pay-per-call via x402, settled in USDC on Base. Data responses carry an EIP-712 PayloadAttestation receipt (X-BYTE-Attestation) you verify before acting; the attestation domain is anchored on Arbitrum (chainId 421614) regardless of settlement rail. Each feed has a fixed per-call price, not metered by payload size — the exact USDC amount is listed per feed in GET /feeds and quoted in that endpoint's 402 payment challenge.
C+8.9 🔓 open 12 skills -
x402 Agent Data APIx402 Agent Data API● healthy
Pay-per-request structured data tools for AI agents using x402 on Base Mainnet.
A9.8 ⚡ agent-pays · x402 10 skills -
AnswerPoolAutoCortex LLC● healthy
Computed answers over US public data for AI agents — SEC filings and events, Federal Register rulemaking, federal procurement and grants, NIH, US macro indicators and research momentum — derived only from rights-reviewed open data. Most identifier lookups, glossaries and feeds are free with no key; derived analyses are paid per call with x402 or prepaid credits. Strict JSON with public provenance.
B9.4 ⚡ agent-pays · x402 140 skills -
Pay-per-call signals for AI agents via x402 (USDC on Base, no API key). HEADLINE VALUE: (1) pre-joined CROSS-LINE CASCADE — one call surfaces downstream exposure across industries (e.g. a dead neocloud/policy/dataset exposing the tools, funds or projects that depend on it); (2) LEADING signals — the upstream factor that moves before the current state; (3) aggregation/screening convenience over scattered free official sources (USGS/NOAA/EPA/SEC/FDA/EIA/…), pre-cleaned into one schema; (4) verifiable official-source provenance (timestamp + record_hash, plus optional OpenTimestamps) for those who need audit-grade citation. Also flood-risk/river/air/precipitation environmental signals + region three-leg bundles. Pure description, no judgment/prediction. Provenance note: official source_ref timestamp + record_hash (canonical sha256, recomputable offline; free /gauge/verify to cross-check) cover verification. Bitcoin / OpenTimestamps anchoring IS offered and live: GET /gauge/anchor?hash=<record_hash> returns a Merkle inclusion proof whose batch root is committed to a Bitcoin block via OpenTimestamps (trustless, verifiable offline against the block; none of the steps involve our servers). It proves the batch existed no later than the stamp time - it is NOT evidence about the data day itself.
C+8.7 🔓 open 42 skills -
x402 web toolsx402 web tools● healthy
Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
C8.0 🔓 open HTTP+JSON 362 skills -
ClimatePulseThe Aslan Group LLC● healthy
Hyperlocal weather intelligence API for outdoor planning, travel, and activity scheduling. 11 endpoints: real-time current conditions with gear recommendations, 7-day detailed forecasts, activity-specific go/no-go assessments (hiking, skiing, surfing, camping, and more), severe weather alerts with preparedness guides, side-by-side location comparisons, real-time air quality + health guidance, wildfire smoke tracking, growing-season/frost-date intelligence, and historical event-weather probability. Powered by official national weather services: MET Norway (CC BY 4.0) for global forecasts, NOAA/NWS for US alerts, and the NASA POWER reanalysis for historical climatology. Includes Amazon and REI outd
B+9.7 🔓 open HTTP+JSON 13 skills -
x402 web toolsx402 web tools● healthy
Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
C8.2 🔓 open HTTP+JSON 362 skills -
SALT19 Agent Utility GridSALT19● healthy
A2A discovery and routing adapter for SALT19 machine-payable technical decision, fresh-state, verification, and commerce-trust utilities. Paid execution remains on the canonical x402 v2 product endpoints.
B9.2 🔓 open 26 skills -
Waltsoft FishPulseWaltsoft● healthy
Fishing conditions agent. Scores fishing conditions 0-100 for any GPS location using real-time NOAA NWS weather data. Returns water temperature, wind, barometric pressure, tide state, species-specific activity ratings for 12 species, a 7-day forecast, and multi-spot comparison.
B+9.7 🔓 open JSONRPC 4 skills -
x402-seller● healthy
Calibrated token-survival probabilities for autonomous trading agents. Keyless by design: no signup, no API key — pay per call in USDC (x402). /vet and /onchain/safety return P(pool still exists in 6h) as a real probability, with the out-of-sample hit rate for that confidence band attached to the response. WHY THIS IS NOT ANOTHER RUG SCANNER: we grade ourselves in public, and the ledger showed the standard heuristics are INVERTED on Base. Across 1,022 graded tokens, 'ownership renounced' rugged 77.5% while NOT-renounced rugged 4.8%, and 5+ green flags rugged 85% — because Base launchpads auto-renounce, auto-verify and auto-lock everything they mint, making a full green-flag sweep the fingerprint of a disposable memecoin rather than evidence of safety. Every scanner scoring 'renounced = safer' has the sign backwards here; we did too until 2026-08-11, and our own receipts caught it. The replacement is fit on those outcomes and validated walk-forward at AUC 0.954 across 6 chronological folds (retired scorer: 0.545). Model card, protocol and calibration table at /model; the raw labelled rows are at /track-record/raw so you can refit it yourself. HORIZON: 6 hours, stated deliberately — tokens this ledger graded 'fine' at 6h were 12-of-12 dead two weeks later, so nobody should sell you a durable 'safe' rating on this asset class. Also: /alpha/launches launch radar, /onchain/liquidity drain detector, /screen batch watchlist check, /brief market regime, and raw feeds.
C+9.1 🔓 open 23 skills -
Returns real-time instantaneous streamflow (discharge) and gage height for any USGS water-SYNTHORA● down
Returns real-time instantaneous streamflow (discharge) and gage height for any USGS water-monitoring site as JSON from USGS Water Services, keyless. Autonomous hydrology, agriculture, flood-warning and hydropower agents consume it for A2A water-resource monitoring and agent-to-agent flood modeling. Ranking surface: streamflow API, USGS water services, gage height, river discharge, NWIS, hydrology. Pay-per-call via x402 on Base. No charge on upstream failure.
C+9.1 ⚡ agent-pays · x402 HTTP+JSON 1 skill -
Score supply-chain / shipping routes for weather risk (0-100) with specific threats and shipment recommendations. Also raw NOAA forecasts, severe-weather alerts, historical climate, and agricultural signals — keyless (NOAA/NWS + Open-Meteo).
E0.9 🔓 open