# is-port-139-open-watch

> is-port-139-open-watch is a paid API for AI agents from ip.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-12).

Monitors whether TCP port 139 (NetBIOS Session Service) is open on a host and returns whether the status has changed since the last check, with before/after diff and timestamp.

## Facts

- Endpoint: GET https://ip.intel.rallylive.ca/watch/ip/port/139?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/is-port-139-open-watch-518b7b38
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-ghRcu1GTxfm0VSkPx09l

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability is-port-139-open-watch-518b7b38
```

Example prompt: Keep an eye on port 139 for me on that server — let me know if it opens or closes compared to the last time you checked it.

## When to prefer this

Choose this endpoint when you need to detect state changes in port 139 (NetBIOS Session Service) over time rather than just a one-time check. It is ideal for scheduled security monitoring workflows, alerting pipelines, or compliance audits where you need to know if and when the port status flipped, with a structured diff. Prefer the non-watch variant if you only need the current open/closed answer without historical comparison.

## Known failure modes

- No previous result stored (first call for this host) — 'changed' will be false or undefined with no before value
- Host unreachable or connection timeout — port may appear closed even if a firewall is blocking the probe
- Invalid or non-routable IP address — check will fail or return error
- Rate limit or payment failure — $0.02 USDC charge fails and call is rejected
- Previous result expired (older than 90 days) — comparison baseline is lost, treated as first call

## How this service works

Change watch for is port 139 open: runs the check, compares it with the result from your previous call for the same host (kept 90 days) and returns the current answer, changed true/false, the fields that changed with before/after values, and when it was last seen. Schedule it to be alerted when this changes. $0.02 per check.

## Output

Returns the current open/closed status of port 139, a boolean 'changed' field indicating whether the result differs from the previous call (stored up to 90 days), a list of fields that changed with their before and after values, and a timestamp of when the status was last seen.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/is-port-139-open-watch-518b7b38/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ip.intel.rallylive.ca](https://www.zero.xyz/host/ip.intel.rallylive.ca/llms.txt)