twilio-sendgrid-engagement-quality — Codex skill: how to install

---
name: twilio-sendgrid-engagement-quality
description: >
  Monitor email program health with SendGrid Engagement Quality (SEQ)
  scores. Covers the SEQ API endpoints, the 5 scoring metrics
  (engagement recency, open rate, bounce classification, bounce rate,
  spam rate), eligibility requirements, and interpreting scores for
  deliverability improvement. Use when diagnosing SendGrid deliverability
  issues or monitoring sender reputation. Requires a SendGrid API key
  (SG.-prefix) — not applicable to the Twilio Email API (comms.twilio.com).
---

## Overview

SendGrid Engagement Quality (SEQ) scores measure how "wanted" your email is by recipients. Higher scores (1-5 scale) correlate with better inbox placement. SEQ is a diagnostic tool — it tells you where your email program is healthy and where it needs improvement.

**Key insight:** SEQ scores are correlated with deliverability. A higher score means more emails land in inboxes, not spam folders.

---

## Eligibility Requirements

Your account must meet ALL conditions to receive scores:
1. **Pro or Premier Email API plan** — SEQ is not available on Free or Essentials plans
2. **Open tracking enabled** in SendGrid settings
3. **Minimum 1,000 messages sent** in the previous 30 days

If not eligible, the `score` and `metrics` fields are omitted from API responses entirely.

---

## The 5 Metrics

All scores range from **1 (poor) to 5 (excellent)**.

| Metric | What it measures | How to improve |
|--------|-----------------|---------------|
| **engagement_recency** | Are you sending to an engaged audience? Based on how regularly messages are opened and clicked. | Remove inactive subscribers. Implement re-engagement campaigns before pruning. |
| **open_rate** | Degree to which your audience opens your messages. | Improve subject lines. Segment audiences by engagement level. |
| **bounce_classification** | Rejection by mailbox providers due to reputation or spam-like content. | Fix content triggering spam filters. Warm IPs properly. Monitor domain reputation. |
| **bounce_rate** | Are you sending to addresses that don't exist? Based on permanent bounces to invalid mailboxes. | Implement double opt-in. Clean lists quarterly. Use Email Validation API before sending. |
| **spam_rate** | Are recipients marking your email as spam? Based on recipients who open then report spam. | Only send to opted-in recipients. Make unsubscribe easy. Match content to expectations set at signup. |

**Note:** The overall `score` is NOT a simple average of the 5 metrics — the weighting formula is opaque. A single low metric (e.g., spam_rate = 1) can drag the overall score significantly.

---

## API Endpoints

### Get Your Scores (Date Range)

`GET /v3/engagementquality/scores`

| Parameter | Required | Description |
|-----------|----------|-------------|
| `from` | Yes | Start date (YYYY-MM-DD, UTC) |
| `to` | Yes | End date (YYYY-MM-DD, UTC) |

**Python**
```python
import os, requests

headers = {"Authorization": f"Bearer {os.environ['SENDGRID_API_KEY']}"}
response = requests.get(
    "https://api.sendgrid.com/v3/engagementquality/scores",
    params={"from": "2026-04-01", "to": "2026-04-23"},
    headers=headers
)

if response.status_code == 200:
    for entry in response.json()["result"]:
        print(f"Date: {entry['date']}, Score: {entry.get('score', 'N/A')}")
        metrics = entry.get("metrics", {})
        for metric, value in metrics.items():
            print(f"  {metric}: {value}")
elif response.status_code == 202:
    print("Scores not yet calculated — try again later")
```

### Get Subuser Scores (Single Date)

`GET /v3/engagementquality/subusers/scores`

| Parameter | Required | Description |
|-----------|----------|-------------|
| `date` | Yes | Date (YYYY-MM-DD, UTC) |
| `limit` | No | Results per page (default 1000, max 1000) |
| `after_key` | No | Pagination cursor |

Returns paginated results with `_metadata.next_params.after_key` for pagination.

---

## Response Patterns

**200 OK** — Scores available:
```json
{
    "result": [{
        "user_id": "12345",
        "username": "myaccount",
        "date": "2026-04-22",
        "score": 4,
        "metrics": {
            "engagement_recency": 4,
            "open_rate": 5,
            "bounce_classification": 3,
            "bounce_rate": 4,
            "spam_rate": 5
        }
    }]
}
```

**202 Accepted** — Scores are calculated asynchronously. Not yet available for the requested date. Retry later.

**Score or metrics omitted** — Account/subuser is not eligible (open tracking off or <1,000 sends in 30 days).

---

## CANNOT

- **Cannot get scores without open tracking enabled** — This is a hard prerequisite. No tracking = no score.
- **Cannot get scores with fewer than 1,000 messages in 30 days** — Low-volume senders are ineligible.
- **Cannot query more than 90 days in the past** — Date range is limited to the last 90 days.
- **Cannot get real-time scores** — Scores are calculated asynchronously (daily). A `202` response means "not ready yet."
- **Cannot determine the exact weighting formula** — The overall score is not a simple average. Individual metric weights are not published.
- **Email Validation API is a separate paid feature** — Referenced in bounce_rate improvement guidance, but requires Pro or Premier plan. Not included in base plan.
- **Subuser endpoint accepts only a single date** — Not a date range. Query one day at a time.

---

## Next Steps

- **Improve bounce rate:** `twilio-sendgrid-suppressions`
- **Track delivery events:** `twilio-sendgrid-webhooks`
- **Account setup:** `twilio-sendgrid-account-setup`