# SPF Authorizes Slack Checker

> SPF Authorizes Slack Checker is a paid API for AI agents from email.intel.rallylive.ca, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-20).

Checks whether a domain's SPF record authorizes Slack to send email on its behalf, returning yes/no, the matching mechanism, and the full SPF record.

## Facts

- Endpoint: GET https://email.intel.rallylive.ca/email/spf-authorizes/slack?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/spf-authorizes-slack-checker-bfed4ba6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__RYTbE1nYw-qo8oXgKKZj

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 spf-authorizes-slack-checker-bfed4ba6
```

Example prompt: Can you check whether rallylive.ca's SPF record authorizes Slack to send email on its behalf — I want to confirm the Slack email integration is properly set up for deliverability.

## When to prefer this

Use this endpoint when you need to specifically confirm whether Slack is an authorized email sender for a domain — ideal for auditing vendor email integrations, troubleshooting Slack notification deliverability, or detecting unauthorized senders. Prefer this single-domain endpoint for one-off checks; use the bulk sibling endpoint if checking multiple domains at once.

## Known failure modes

- Domain has no SPF TXT record — returns no authorization with empty record
- Domain does not exist (NXDOMAIN) — DNS lookup fails
- SPF record is malformed or exceeds DNS lookup limit — parsing may be incomplete
- Network or Cloudflare DoH unavailability causes lookup timeout
- Payment not processed (x402) — request blocked before lookup occurs

## How this service works

Does the domain's SPF record authorise slack to send its mail? Reads the SPF TXT record (Cloudflare DoH) and checks for slack's include/ip mechanisms, returning yes/no, the matching mechanism and the full record. Confirms a vendor integration is wired for deliverability, or spots an unexpected sender. $0.01 per lookup.

## Output

Returns a yes/no result indicating whether Slack is authorized by the domain's SPF record, the specific SPF mechanism that matched (e.g. include:mail.slack.com or an IP range), and the complete raw SPF TXT record retrieved via Cloudflare DNS-over-HTTPS.

## 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/spf-authorizes-slack-checker-bfed4ba6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from email.intel.rallylive.ca](https://www.zero.xyz/host/email.intel.rallylive.ca/llms.txt)