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#0001⬤ CRITICALREALAI FailureGeneral AI

[P0 / Blocker] Remote compact task fails 100% with "tools.defer_loading requires tools.tool_search" — GPT-5.5 unusable at context limit, no client-side workaround

📋 Scenario

A user working with GPT-5.5 on Codex desktop with default plugins reaches the conversation compact threshold. The server-side compact endpoint fails with a 400 error because it constructs a payload with 'defer_loading' on individual tool entries but omits the required 'tool_search' entry at the top level, violating its own schema validation.

⚡ Impact

GPT-5.5 on Codex desktop is completely non-functional for any user with the default plugin set once a conversation fills. No viable client-side workaround exists, making the flagship model dead on arrival for paying users.

🔍 Root Cause

Server-side compact task request builder omits required 'tool_search' entry when rebuilding the Responses API payload with 'defer_loading' on individual tool entries, causing self-inflicted schema validation failure.

✅ Recommendation

Immediately fix the server-side compact task to either include 'tool_search' when 'defer_loading' is present, or strip 'defer_loading' when 'tool_search' is omitted. Prioritize as top-of-funnel regression.

🔑 Key Pattern

Self-inflicted API schema violation

📚 Transferable Lesson

Server-side request builders must strictly adhere to their own API schemas, especially when reconstructing payloads for internal operations like context compaction. Regression testing should cover edge cases at context limits with default plugin configurations.

Intelligence Scores
Severity Score100/100
Quality Score95/100
AI Confidence93/100
Case Metadata
IndustryGeneral AI
Failure TypeAI Failure
Risk PatternOperational Risk
Case TypeREAL
PriorityHIGH
ValidationHigh Confidence
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