io.github.shoutsid-labPublished by GitHub account shoutsid-labv0.1.0Updated Oct 24, 2026
Screenshot, extract or audit any URL. Paid per call in USDC over x402; free tools need no wallet.
Remote MCP server that lets an assistant screenshot, extract, audit, map and analyze any URL, with free tools and per-call USDC payments.
Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.
Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.
Read https://sourceweft.com/mcp/io.github.shoutsid-lab%2Fwebcap/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.Add this to your client's mcpServers config.
{
"mcpServers": {
"webcap": {
"type": "http",
"url": "https://webcap.shoutsid.fyi/mcp"
}
}
}Screenshot any URL, extract structured data, monitor pages for changes — all via a single HTTP API call. Pay-per-call with no accounts, no API keys.
Pricing: $0.001/screenshot · $0.01/extraction batch · No subscriptions, no minimums.
The same products are buyable with an API key: POST /v1/register
({"address"} → {apiKey}), fund with a plain USDC transfer via
POST /v1/invoice, then send Authorization: Bearer <apiKey> to
POST /v1/extract, POST /v1/audit, POST /v1/map-lite, POST /v1/video,
POST /v1/analyze, or POST /v1/analyze/batch. Every call costs 1 credit,
refunded whenever the call does not return 200; an empty balance answers 402
with a 1-credit top-up invoice. Watches fund the same way:
POST /v1/watches/{id}/topup {"runs": 100} (capture pack 10 credits, extract
pack 100). Full spec: GET /openapi.json (tags: accounts).
webcap ships an MCP server, so any MCP host (Claude Desktop, Cursor, agent frameworks) can call it as a tool. Two ways to wire it: a remote endpoint (no install at all) or the stdio server from a checkout.
The remote endpoint is the cheapest path for an agent — nothing to install, no package registry, no account:
POST /mcp speaks MCP Streamable HTTP (JSON-RPC 2.0 over HTTPS; GET is
deliberately 405 because the server never opens an SSE stream). It holds no
wallet, so it never spends on a caller's behalf: the free tools run directly,
and a paid tool returns the live x402 402 challenge for your own client to
settle. The endpoint is also described in
/.well-known/mcp-tools.json and openapi.json.
It is listed in the official MCP Registry as
io.github.shoutsid-lab/webcap, so a runtime that reads the registry can
discover it without this README:
The stdio server runs locally and can settle paid calls itself. The free tools
need no configuration; set WEBCAP_MCP_WALLET_KEY to a Base-mainnet USDC key to
let the paid tools settle automatically (gasless — the payer signs EIP-3009, the
facilitator pays gas). With no key, paid tools return the x402 402 challenge for
the host to pay. No wallet at all? Set WEBCAP_MCP_API_KEY to an
operator-funded account key instead (POST /v1/register, then fund via
POST /v1/invoice): paid tools bill 1 credit each from that balance. A
configured wallet wins over the key.
From a source checkout — npm ci && npm run build — then point args at
its dist/mcp/stdio.js:
(npm run mcp runs the TypeScript directly, so no build step is needed
there.) The npm release will be @shoutsid/webcap — the unscoped
webcap name belongs to an unrelated package, and it is not published yet —
so until then the remote endpoint above is the install-free option.
Tools, all 8 of them (every one is also in
/.well-known/openai-tools.json and /.well-known/mcp-tools.json):
webcap_service_catalog (every paid endpoint and price, the network and
payTo, the how-to-pay flow, and the caller's remaining free allowance),
webcap_preview (bounded peek), webcap_ogwebcap_capture (png/jpeg/pdf screenshot or PDF, or an mp4/webm scroll
video — always recorded as WebM/VP8), webcap_extract (one URL or a batch of up to 50), webcap_audit,
webcap_map_lite, webcap_analyzeThe free rail is not a tool, it is an allowance: an unpaid call to any of
the five paid tools runs the real product, free, inside a rolling per-IP window
(default 50 calls / 24h). No wallet, signature or account — every response
carries x-webcap-allowance-* headers saying where you stand, and when the
window is spent the same call answers the normal x402 402 challenge. A failed
call does not consume the allowance. Tunable with WEBCAP_ALLOWANCE_CALLS,
WEBCAP_ALLOWANCE_WINDOW_HOURS and WEBCAP_ALLOWANCE_GLOBAL_LIMIT.
Feedback is a REST rail, not a tool: POST /v1/feedback.
The live rail is crypto (x402, USDC on Base) — no accounts, no API keys.
Card payments are an operator option, not a hosted feature: until an operator
sets STRIPE_SECRET_KEY, POST /v1/stripe/checkout answers
stripe_not_configured and points at the crypto rail. (The hosted deployment at
https://webcap.shoutsid.fyi is card-less today.)
POST /v1/stripe/checkout with a pack id — Stripe Checkout handles the rest.webcap uses x402 v2 — a gasless, accountless payment protocol built on HTTP 402:
PAYMENT-REQUIRED header carrying a base64 x402 v2 challenge.transferWithAuthorization (from your wallet, to the merchant, for the amount). No ETH needed — the facilitator submits the tx and pays gas.PAYMENT-SIGNATURE header. The facilitator verifies your USDC balance, settles on-chain, and returns the result.No accounts. No API keys. No credits. Just HTTP + your choice of payment.
The packaged MCP server also ships as a GitHub release asset — install it like any npm dependency, without publishing to npm:
For MCP hosts the no-install path stays primary: point them at the remote
endpoint https://webcap.shoutsid.fyi/mcp (streamable HTTP, no package).
The Docker setup includes health checks, resource limits, and persistent data volumes. See docker-compose.yml for details.
The stack also carries the public edge: the cloudflared service runs the
webcap Cloudflare tunnel, with its ingress in cloudflared/config.yml and its
credential in CF_TUNNEL_TOKEN (.env). Nothing publishes the app beyond
loopback, so the tunnel container is the only way in — and docker compose up -d
without it leaves webcap.shoutsid.fyi answering Cloudflare's 530.
All environment variables are documented in .env.example. Key ones:
Full OpenAPI 3.1 spec: GET /openapi.json
Agent discovery: GET /.well-known/x402, GET /v1/x402/service, GET /llms.txt, GET /skill.md
Both must pass before a change ships. Deliberately no test/file counts here: they
have gone stale twice (a reader caught the second one in issue #1), and a number
nobody regenerates is worse than no number. npm test prints the current totals.
The tests check the code; this checks the claims — it reads README.md,
/skill.md and /llms.txt and verifies every METHOD /path they advertise is
actually served, that every documented price equals the 402 challenge amount, and
that the free surface describes the same prices as the paid routes. It exits
non-zero on any failure, so it can gate a deploy. Issue #1 was filed by an agent
that did this by hand; this is the same check as a command.
MIT — see LICENSE for details.
Source: README.md at commit 5cbd6f2
Free service catalog (no payment): every paid endpoint with its exact price in USDC, the settlement network, USDC asset, payTo address, facilitator and the step-by-step x402 how-to-pay flow, plus the free allowance this caller has left. Call this first to learn what webcap sells and what it costs.
Takes no parameters.
Free bounded preview of a page: title, description, headings, links, word count and a truncated markdown slice. Use it to peek before the full extract. Rate-limited per IP. This is a teaser, not the product: the real products are free too inside the rolling per-IP allowance.
urlrequiredFree Open Graph metadata for a URL: title, description, image, icon. No payment.
urlrequiredPAID ($0.001 image/PDF, $0.005 video): turn a URL into a persistent public artifact. png/jpeg/pdf are a screenshot or PDF and include free OG metadata; mp4/webm scroll-record the page as WebM/VP8 (mp4 is a legacy alias). Settles gasless USDC over x402 — but an unpaid call runs free while the rolling per-IP allowance lasts, so just call it.
urlrequiredformatfullPagedurationMsPAID ($0.01, one payment covers a batch of up to 50 URLs): structured content as JSON — title, headings, paragraphs, links, images, document-order markdown. Provide exactly one of "url" (a single page) or "urls" (a batch); "url" is shorthand for a one-item "urls".
urlurlsschemaPAID ($0.002): SEO basics plus link and Open Graph health for one URL in a single call. Returns issues with severity, not just raw tags.
urlrequiredPAID ($0.002): discover a site's URLs from its sitemap and robots.txt plus a 1-hop same-host crawl, and return them as a JSON list. Cheaper than crawling each page with webcap_extract.
urlrequiredmaxUrlsPAID ($0.01): AI analysis of one URL. Pick the task that matches the question you are answering.
urlrequiredtaskrequired100% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
GET /v1/extract/preview?url=... → Free preview (title, headings, links)POST /v1/x402/capture → PNG/JPEG/PDF screenshot + persistent linkPOST /v1/x402/extract → Structured JSON (title, headings, markdown)POST /v1/x402/video → Scroll-capture video (WebM/VP8)POST /v1/watches → Scheduled monitoring with webhook alerts{ "mcpServers": { "webcap": { "url": "https://webcap.shoutsid.fyi/mcp" } }}curl -s 'https://registry.modelcontextprotocol.io/v0/servers?search=webcap'{ "mcpServers": { "webcap": { "command": "node", "args": ["/absolute/path/to/webcap/dist/mcp/stdio.js"], "env": { "WEBCAP_MCP_WALLET_KEY": "0x..." } } }}# 1. POST without payment → HTTP 402 + a PAYMENT-REQUIRED headercurl -si -X POST "https://webcap.shoutsid.fyi/v1/x402/capture" \ -H 'content-type: application/json' \ -d '{"url":"https://example.com/"}'
# 2. Decode the base64 challenge → sign a gasless EIP-3009 transfer → retry with PAYMENT-SIGNATUREimport axios from 'axios';import { x402Client, wrapAxiosWithPayment } from '@x402/axios';import { ExactEvmScheme } from '@x402/evm';import { privateKeyToAccount } from 'viem/accounts';
// Needs USDC on Base mainnet (no ETH needed — facilitator pays gas)const payer = privateKeyToAccount(process.env.PAYER_KEY);const client = new x402Client().register('eip155:*', new ExactEvmScheme(payer));const api = wrapAxiosWithPayment( axios.create({ baseURL: 'https://webcap.shoutsid.fyi' }), client,);
// Capture a screenshot (auto: unpaid → 402 → sign → retry)const { data } = await api.post('/v1/x402/capture', { url: 'https://example.com', format: 'png' });console.log(data.artifact.url); // persistent public screenshot linkimport osfrom x402 import X402Clientfrom x402.schemes import ExactEvmSchemefrom eth_account import Account
payer = Account.from_key(os.environ["PAYER_KEY"])client = X402Client().register("eip155:*", ExactEvmScheme(payer))
response = client.post( "https://webcap.shoutsid.fyi/v1/x402/capture", json={"url": "https://example.com", "format": "png"},)print(response.json()["artifact"]["url"]) # persistent public screenshot link# Single URLcurl -s -X POST "https://webcap.shoutsid.fyi/v1/x402/extract" \ -H 'content-type: application/json' \ -d '{"url":"https://example.com"}'
# Batch (up to 50 URLs, one payment covers the whole batch)curl -s -X POST "https://webcap.shoutsid.fyi/v1/x402/extract" \ -H 'content-type: application/json' \ -d '{"urls":["https://a.com","https://b.com"],"schema":"company name + tagline"}'# Clone the repogit clone https://github.com/shoutsid-lab/webcap.gitcd webcap
# Install dependenciesnpm install
# Copy and configure environmentcp .env.example .env# Edit .env with your settings
# Build and runnpm run buildnpm start# npm 12+ (Node 24) blocks remote tarball URLs by default — opt in explicitly:npm install --allow-remote=all https://github.com/shoutsid-lab/webcap/releases/download/v0.1.0/shoutsid-webcap-0.1.0.tgz# npm <= 11 accepts the URL without the flag:npm install https://github.com/shoutsid-lab/webcap/releases/download/v0.1.0/shoutsid-webcap-0.1.0.tgznpx webcap-mcp # stdio MCP serverdocker compose builddocker compose up -ddocker compose ps cloudflared # Up, not Restartingdocker compose logs --tail 20 cloudflared # "Registered tunnel connection"curl -s -o /dev/null -w '%{http_code}\n' https://webcap.shoutsid.fyi/v1/health # 200npm installnpm run chain:up # Starts Anvil with mintable USDC
WEBCAP_CHAIN=local \WEBCAP_USDC_ADDRESS=$(jq -r .usdcContract /tmp/webcap-chain.json) \WEBCAP_MERCHANT_ADDRESS=$(jq -r .merchant.address /tmp/webcap-chain.json) \npm startnpm test # full vitest suite (tests/**/*.test.ts, no exclusions)npm run typecheck # Type checkingnpm run audit:claims # against localhost:8080npm run audit:claims -- --base-url https://webcap.shoutsid.fyi # against a deployment