[Bug]: Grok 4.1 Fast 'reasoning.encrypted' data format causing Provider returned error in v3.2.4

[slowtokki0409]

Description

When using x-ai/grok-4.1-fast (via OpenRouter) as an agent model in oh-my-opencode v3.2.4, the model fails to return a response and throws a "Provider returned error".

Root Cause Analysis

• Direct API Test: A direct curl call to OpenRouter with x-ai/grok-4.1-fast works perfectly (response received in < 3s).
• In-App Failure: In the oh-my-opencode interface, it fails immediately.
• Specific Observation: Grok 4.1 Fast returns reasoning data in an encrypted format ("type":"reasoning.encrypted"). The new reasoning/thinking display engine in v3.2.4 likely fails to parse this specific format, leading to a crash or connection termination before the content is streamed.

Steps to Reproduce

1. Configure an agent with "model": "x-ai/grok-4.1-fast" in oh-my-opencode.json.
2. Attempt to chat with the agent.
3. Observe "Provider returned error" while the model is attempting to "think".

Environment

• Version: v3.2.4
• Provider: OpenRouter
• Model: x-ai/grok-4.1-fast

Expected Behavior

The system should either handle/ignore the reasoning.encrypted block or simply stream the content part once reasoning is completed.

[code-yeongyu]

Triage: FIX_NEEDED

Classification: Confirmed. The reasoning.encrypted content block type from Grok models is not handled anywhere in the codebase.

Root Cause

The reasoning/thinking system only recognizes three types (defined in src/hooks/session-recovery/types.ts):

type ThinkingPartType = "thinking" | "redacted_thinking" | "reasoning"

reasoning.encrypted is not recognized, causing failures when the streaming handler encounters this unknown type.

Affected Files (9 locations)

1. src/hooks/session-recovery/types.ts — ThinkingPartType definition
2. src/hooks/session-recovery/storage.ts — hasContent() / THINKING_TYPES
3. src/tools/background-task/tools.ts — 5 locations checking part.type === "reasoning"
4. src/tools/delegate-task/executor.ts — reasoning part filtering
5. src/tools/call-omo-agent/tools.ts — reasoning part filtering
6. src/hooks/thinking-block-validator/index.ts — validation
7. src/features/background-agent/manager.ts — content detection
8. src/features/background-agent/result-handler.ts — content checks
9. src/hooks/unstable-agent-babysitter/index.ts — content extraction

Fix

Add "reasoning.encrypted" to ThinkingPartType and update all 9 files to handle it alongside "reasoning". The encrypted reasoning content should be treated as opaque (no text extraction) but recognized as a valid thinking block to prevent crashes.