fix(cli): exclude gpt-5.6-terra models from explicit prompt cache breakpoints

[chrarnoldus]

Summary

• Fixes the error reported in feat(cli): set prompt cache breakpoints on stable prefix and user query before environment details #13022 (prompt_cache_breakpoint is not supported on this model on GPT-5.6 Terra).
• Exclude -terra model variants from manual promptCacheBreakpoint: { mode: 'explicit' } treatment on the OpenAI provider, falling back to standard automatic caching.
• Retain explicit breakpoints for base GPT-5.6, Azure OpenAI, and Kilo Gateway.

[kilo-code-bot]

SUGGESTION: Consider matching -terra instead of a bare terra substring

includes("terra") matches anywhere in the model id, so a hypothetical future non-Terra model whose name merely contains the substring (e.g. a terraform-themed variant) would silently lose explicit breakpoints. includes("-terra") would still catch gpt-5.6-terra and prefixed gateway ids like openai/gpt-5.6-terra while avoiding that false positive. This is consistent with the broad includes checks already used nearby (claude, anthropic), and the failure mode is a graceful fallback to automatic caching, so feel free to reject.

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Reply with @kilocode-bot fix it to have Kilo Code address this issue.

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	0
WARNING	0
SUGGESTION	1

Issue Details (click to expand)

SUGGESTION

File	Line	Issue
packages/opencode/src/provider/transform.ts	338	includes("terra") is a broad substring match; includes("-terra") would avoid hypothetical false positives

The fix is correct and well-scoped: the Terra exclusion sits inside the existing kilocode_change block, covers both supportsPromptCacheBreakpoint call sites (caching gate and provider options), and the new test genuinely exercises it (non-zero cost bypasses the ChatGPT-subscription heuristic, so the test fails without the new line). Changeset is present and user-facing. No memory-leak or security concerns — pure predicate change.

Fix these issues in Kilo Cloud

Files Reviewed (3 files)

• packages/opencode/src/provider/transform.ts - 1 issue
• packages/opencode/test/provider/transform.test.ts - 0 issues
• .changeset/exclude-terra-from-prompt-cache-breakpoint.md - 0 issues

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_{Reviewed by kimi-k3 · Input: 58.4K · Output: 6.6K · Cached: 237.5K}

_{Review guidance: REVIEW.md from base branch main}