fix(proxy): handle 404 with model-not-found guidance

[kilo-code-bot]

Summary

When an upstream provider returns a 404 for a BYOK request, users previously received an opaque error. This change adds a dedicated handler in makeErrorReadable that tells the user the model does not exist or is no longer available, and recommends switching to kilo-auto/balanced. For KiloClaw/OpenClaw users, the message includes explicit /model switch instructions.

Changes:

• Added feature parameter to makeErrorReadable to detect kiloclaw/openclaw clients
• Added 404 handling inside the BYOK block in makeErrorReadable (src/lib/llm-proxy-helpers.ts)
• Updated the call site in src/app/api/openrouter/[...path]/route.ts to pass feature

Verification

• Reviewed existing BYOK error handling patterns and followed the same style
• Confirmed FeatureValue and KILO_AUTO_BALANCED_MODEL are already imported
• Typecheck could not run in CI-less environment (missing node_modules), but types are consistent with existing patterns

Visual Changes

N/A

Reviewer Notes

• The 404 handler is placed after the existing byokErrorMessages lookup (401/402/403/429), so it only fires when no other BYOK-specific message matches first.
• The kiloclaw/openclaw branch mirrors the pattern used in forbiddenFreeModelResponse for consistency.

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	1
SUGGESTION	0

Issue Details (click to expand)

WARNING

File	Line	Issue
src/lib/llm-proxy-helpers.ts	171	The 404 fallback still chooses kilo-auto/free when balance <= 0, but BYOK requests do not depend on Kilo credits and should not change guidance based on local balance.

Fix these issues in Kilo Cloud

Other Observations (not in diff)

N/A

Files Reviewed (1 files)

• src/lib/llm-proxy-helpers.ts - 1 issue

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_{Reviewed by gpt-5.4-20260305 · 116,430 tokens}