Blog
February 25, 2025

DID Health Monitoring: How We Keep Your Numbers Clean

How Trunx continuously scores phone number health, detects reputation issues before they become spam flags, and automatically rotates numbers to maintain connect rates.

Wei Lin
Wei Lin
3 mins read

DID Health Monitoring: How We Keep Your Numbers Clean

If you're running outbound campaigns at any scale, your phone numbers are your most valuable asset. A flagged number means unanswered calls, wasted compute, and lost revenue.

Trunx monitors every DID in your pool continuously — scoring health, detecting anomalies, and rotating numbers automatically so you don't have to think about it.

The Problem

Telecom carriers and spam detection services are getting aggressive about flagging outbound numbers. A number that worked fine yesterday can get flagged today based on:

  • High call volume from a single number
  • Low answer rates
  • Short call durations (indicating people hanging up immediately)
  • Reports from recipients

Most teams discover a number is burned after their connect rates have already tanked. By then, the damage is done.

How Health Scoring Works

Every call made through Trunx generates a health event. We compute a rolling health score from the last 50 calls per DID using a weighted formula:

FactorWeightWhat It Measures
Answer rate30%Are people picking up?
Average duration25%Are calls substantive or instant hangups?
Human engagement20%Did a human (not voicemail) answer?
No-answer trend15%Is the no-answer rate increasing?
Spam clean10%Has the number been flagged by reputation services?

The result is a score from 0-100. Numbers above 70 are healthy. Below 50, they're automatically cooled down.

Automatic State Management

DIDs cycle through four states:

  • Active — In use, accepting calls
  • Warming — New number, gradually increasing volume
  • Cooling — Pulled from rotation, resting after health drop
  • Burned — Flagged by carriers, removed from pool

Transitions happen automatically. A DID lifecycle job runs every 60 seconds, checking health scores and reputation data, moving numbers between states without human intervention.

Anomaly Detection

Beyond individual health scores, Trunx runs comparative anomaly detection across your entire DID pool. If one number's answer rate drops significantly compared to the pool average (using z-score analysis with a configurable threshold), it gets flagged before the health score alone would catch it.

This catches subtle issues — a number that's still technically "healthy" but performing worse than its peers.

Reputation Monitoring

Health scoring measures how your numbers perform. Reputation monitoring checks how the outside world sees them.

Trunx checks every active DID against multiple external reputation databases. A daily reputation audit job updates scores automatically. Numbers with reputation issues get flagged immediately.

What This Means For You

If you're running campaigns through Trunx:

  1. Numbers warm up automatically — New DIDs start with low volume and ramp up
  2. Unhealthy numbers cool down — Before they get flagged by carriers
  3. Burned numbers get replaced — No manual intervention needed
  4. Connect rates stay high — Because your caller ID pool stays clean

The DID selection algorithm picks the best number for each call based on health score, local presence matching, and warming schedule. You don't pick which number to use — Trunx picks the healthiest one.

Getting Started

DID health monitoring is on by default for every Trunx account. Check your DID health scores in the dashboard or via the API.

For the technical details on health scoring and reputation monitoring, see the DID Health guide and Reputation API reference.

Wrap-up

Telecom infrastructure shouldn't slow you down. Trunx fits into your workflow — whether you're building voice AI agents, managing outbound campaigns, or scaling SMS at 2am.

If that sounds like the kind of tooling you want to use — try Trunx or join us on Discord.