Why has Avalara's AvaTax API experienced a 15% drop in successful calls over the past month?

Introduction

The recent 15% drop in successful calls to Avalara's AvaTax API over the past month is a critical issue that demands immediate attention. This decline in API performance not only affects our service reliability but also impacts our customers' operations and potentially our revenue. I'll approach this problem systematically, focusing on identifying the root cause, validating hypotheses, and developing both short-term fixes and long-term solutions.

Step 1

Clarifying Questions (3 minutes)

• Given the sudden drop, I'm wondering about recent changes. Have there been any significant updates to the AvaTax API or related systems in the past 1-2 months?

Why it matters: Recent changes often correlate with performance issues. Expected answer: Yes, there was a minor update to improve calculation speed. Impact on approach: If confirmed, we'd focus on regression testing and rollback options.

• Considering the 15% drop, I'm curious about the distribution. Is this decline uniform across all customers, or are certain segments more affected?

Why it matters: Helps identify if the issue is global or segment-specific. Expected answer: The drop is more pronounced among high-volume enterprise customers. Impact on approach: We'd prioritize investigating enterprise-specific integrations or usage patterns.

• Looking at the error patterns, I'm thinking about potential infrastructure issues. Have we observed any changes in server load or response times coinciding with this drop?

Why it matters: Infrastructure problems can cause widespread API failures. Expected answer: There's been a slight increase in average response times. Impact on approach: We'd focus on scaling and performance optimization strategies.

• Considering external factors, I'm wondering about any changes in tax regulations. Have there been any significant tax law updates in major jurisdictions recently?

Why it matters: Tax calculation complexity could impact API success rates. Expected answer: No major changes, but some minor updates in a few states. Impact on approach: We'd investigate the API's ability to handle complex tax scenarios.