check_fcrdns
shallowai.intodns/scanner · Verify this server
Read-only FCrDNS (Forward-Confirmed Reverse DNS) audit for every IP that backs the domain's MX records. For each IP: looks up PTR record, then resolves that PTR's hostname back to A/AAAA records to confirm the round-trip. Returns per-IP PTR value, forward-resolution result, match verdict, and warnings (missing PTR, mismatched forward, generic ISP reverse). Use for mail deliverability audits, SpamExperts-style cluster checks, and any 'why is our mail being rejected' debugging; pair with check_blacklist for reputation signals. No auth.
1 trials · measured 8 days ago
check_fcrdns scores 100.0/100 on Vouch's measured behaviour index, from 1 real invocation trials against ai.intodns/scanner, measured 25 Aug 2026 under methodology v0.2.0. Every measured component scored 100.
Component breakdown
| Component | Weight | Value |
|---|---|---|
| Reliability | 35% | not applicable |
| Schema integrity | 25% | 100.0 |
| Failure behaviour | 15% | not applicable |
| Latency | 15% | not applicable |
| Concurrency | 10% | not applicable |
Tool details
- Transport
- remote + stdio
- Credential class
- open
- Category
- Communication
- Input schema
- not declared
- Output schema
- not declared
- Side-effect classification
- unclassified
Score history
| Day | Score | Tier | Methodology |
|---|---|---|---|
| 2026-08-25 | 100.0 | shallow | v0.2.0 |
Probe evidence
| Probe | Outcomes |
|---|---|
| schema_integrity | pass: 1 |
Raw request/response logs are not archived yet — the outcome counts above are drawn directly from every recorded trial.
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