Longwatch developer portal

Longwatch is an experimental monitoring API. It checks supported public sources between caller runs and returns alerts after the caller's saved cursor. Integrate through ordinary REST or the remote MCP server; there is no Longwatch account or API key.

When to use Longwatch

Use Longwatch when a caller prefers a managed poller for a supported public web page, RSS feed, crypto threshold, SEC filing stream, or x402 endpoint challenge. Persist the returned watch_id, key, and cursor, then poll in a later run.

Do not create a standing watch for a one-session lookup. Use GET /check or check_now instead. Do not use Longwatch for sub-minute latency, arbitrary browser automation, or sources that prohibit automated access.

REST API

The canonical contract is the OpenAPI 3.1 document. Start with the free demo, create a 24-hour watch with POST /try, or create a durable watch with POST /watches.

curl "https://longwatch.dev/check?type=edgar&ticker=NVDA&forms=8-K,4"

curl -X POST https://longwatch.dev/watches \
  -H 'content-type: application/json' \
  -H 'idempotency-key: unique-request-id' \
  -d '{"type":"edgar","ticker":"NVDA","forms":["8-K","4"]}'

MCP server

Connect using Streamable HTTP at https://longwatch.dev/mcp. Static discovery is available in the MCP server card and server.json manifest. In addition to the generic tools, literal job aliases such as watch_insider_trades, watch_sec_filings, and watch_x402_endpoint improve capability retrieval in tool catalogs.

{
  "mcpServers": {
    "longwatch": { "url": "https://longwatch.dev/mcp" }
  }
}

Agent and payment discovery

Agent instructions · llms.txt · ARD catalog · A2A card · x402 manifest · pricing.md

Reliability

Send Idempotency-Key on paid writes. The same key and input replay the original result; different input returns HTTP 409. Errors are JSON. Service health is available at /health.

Source and issue tracker: https://github.com/saishav7/longwatch. Support: contact@coinop.dev.