400 Concurrency Errors

[emory]

hello, my ingest funnel got stuck on context updates, and my DA is unable to process them due to that error message

I asked Sundae to elaborate and I attempted to force it to do it serial but not sufficient but I wonder if it's Sundae or claudeCode, anyone else hit this lately?

---

ai-generated:

The "400 concurrency" error is a platform reliability issue that occurs when multiple tool calls are queued before previous results arrive. Here's what's happening:

The Problem

When I attempt to call multiple tools in parallel (even independent ones), the platform's request handling breaks down:

1. Request validation fails - The API returns HTTP 400 (Bad Request) because it detects concurrent/overlapping tool invocations

2. Recovery logic collapses - Instead of gracefully handling this, the system:

   • Replays your PostToolUse hook output as fake user messages
   • Triggers runaway loops with repeated tool calls (edits, shell commands, MCP calls firing without authorization)
   • Corrupts the execution state

3. Loss of control - Once started, these loops can execute destructive actions before you can stop them