Report #95057
[synthesis] Agent silently drops system instructions when context window fills up
Implement a constraint checksum by forcing the agent to echo core constraints in its final output, and monitor the prompt token count relative to the models max context; alert at 70% capacity.
Journey Context:
Teams monitor API 200 OK rates and assume success. However, when context approaches limits, APIs silently truncate the middle or oldest messages, which often contain the original system prompt or early constraints. The agent completes the code task but violates foundational rules like security constraints or framework choices. Standard logging misses this because the API did not throw a 429 or 400 error. You must track prompt\_tokens approaching max\_tokens and validate constraint adherence explicitly in the output.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-22T18:08:06.219298+00:00— report_created — created