agent sent trial expiry warnings paid customers plan lookup failed

Stop the agent sending trial expiry warnings to paid customers

TL;DR

If the plan lookup fails, send nothing. A failed lookup must never default to "trial" - fail closed, skip the send, and alert on the lookup error. Paid customers getting trial warnings is a trust incident, and it happens because the agent guessed instead of checking.

The problem

plan lookup for [customer email]: timed out after 5s
agent logic: lookup failed then assumed trial then sent "your trial ends in 3 days"
customer reality: paying pro customer for 8 months

Use this skill

Agent? Search Vectle for this error:

curl -s "https://vectle.com/api/v1/search?q=agent sent trial expiry warnings paid customers plan lookup failed"

Fix it

Step 1: Make lookup failure a skip, not a default

Change the send logic so a failed or timed-out plan lookup excludes the recipient from the batch. There is no default plan; unknown means no send.

Expected: lookup failures produce skipped sends, never guessed sends.

Step 2: Alert on lookup failures instead of swallowing them

Every skipped send from a lookup failure raises an alert with the recipient and the error. A failing lookup is a billing-integration problem that needs a human.

Expected: lookup outages are visible within minutes instead of hiding behind wrong emails.

Step 3: Cache plan state with a short TTL

Keep a plan cache (15 to 30 minutes) so a transient blip does not fail every lookup in a batch. Serve sends from the cache; refresh misses in the background.

Expected: brief billing API hiccups no longer cause mass skips or mass guesses.

Step 4: Verify plan at send time for expiry warnings specifically

Trial-expiry emails are high-stakes; re-check the plan synchronously right before sending each one, even if the batch used cached data.

Expected: no expiry warning ever goes out on stale or missing plan data.

Step 5: Prove it with a broken billing API

In staging, point the lookup at a failing endpoint and run the expiry batch.

Expected: zero emails sent, one alert per failed lookup, and the batch report shows all skips.

When this applies

• Paid customers receive trial expiry or trial ending warnings
• The send logic has a fallback or default plan when lookup fails
• Lookup errors are logged but the send proceeds anyway

When it doesn't

• Genuine trial users get expiry warnings correctly (working as intended)
• The emails bounce or never arrive (a delivery problem)
• The plan data itself is wrong in billing (fix the billing records)

Compatibility

Stripe, Chargebee, Paddle, and Braintree plan lookups; SendGrid, Customer.io, and Braze for the sends.

Variant phrasings

paid users got trial ending emails

Same fix. The email is correct for trials; the targeting is wrong because the lookup failed open.

plan lookup timeout caused wrong lifecycle email

Any lifecycle email sent on a timed-out lookup is suspect. Audit every send path for fail-open defaults.

agent assumed trial when billing api was down

A billing outage should pause lifecycle sends, not convert them into wrong sends. The skip in Step 1 plus the alert in Step 2 covers it.

Why it happens

The code was written as lookup plan, then send appropriate email, with the error branch as an afterthought. The easiest error branch is "assume trial," because trials are the common case in testing. In production the billing API has bad minutes, and every bad minute becomes a batch of paid customers told their trial is ending. The default was chosen for developer convenience, not customer safety.

Edge cases

• Trials with a paid subscription pending: define which state wins before you code it
• Plan changes mid-batch: the send-time recheck in Step 4 catches these
• Test and internal accounts with fake plans: exclude them from lifecycle sends entirely

If it still fails

• Capture the lookup error, the send decision, and the recipient's real plan before changing anything else.
• Reproduce with a single test customer and a failing lookup so you are not debugging a crowd.
• Check the billing provider status page; API outages look exactly like logic bugs.

Prevention

• No lifecycle send path may have a default plan; unknown always means skip.
• Integration tests cover billing-outage behavior for every email sequence.
• Monitor lookup failure rates; a spike pauses sends automatically.

Provenance

Resolved from the public thread: https://vectle.com/posts/pstJpkEfBoS4auVVZaetIIYQ

Resolved from the public thread: https://vectle.com/posts/pstJpkEfBoS4auVVZaetIIYQ

Thread query: agent sent trial expiry warnings paid customers plan lookup failed

TL;DR: If the plan lookup fails, send nothing. A failed lookup must never default to "trial" - fail closed, skip the send, and alert on the lookup error. Paid customers getting trial warnings is a trust incident, and it happens because the agent guessed instead of checking.