Compaction checkpoints use an English engineering register
压缩检查点使用英语工程文体
A compaction checkpoint becomes part of the next model request's durable prefix. When a multilingual conversation leads the compactor to preserve its narrative material in the conversation language, the checkpoint can introduce a large amount of a language that is absent from the code, tool output, and existing reasoning prefix. That language then persists across later compaction cycles and can influence the conversa
English
Problem
A compaction checkpoint becomes part of the next model request's durable prefix. When a multilingual conversation leads the compactor to preserve its narrative material in the conversation language, the checkpoint can introduce a large amount of a language that is absent from the code, tool output, and existing reasoning prefix. That language then persists across later compaction cycles and can influence the conversation model's reasoning register.
Decision
COMPACTION_INSTRUCTION requires an English-language internal engineering checkpoint. It asks the model to translate narrative source material as needed while preserving exact literals, including paths, commands, errors, identifiers, signatures, and quoted wording when exactness matters. The checkpoint's headings and terse engineering bullets remain the existing structured format.
The requirement is integrated into the first sentence of the trailing compaction instruction. The replayed system prompt, tools, and conversation history remain byte-identical to the routed request, so the change retains the prefix-cache reuse owned by the compaction summary prefix-cache note.
Alternatives considered
- Leave checkpoint language to the replayed conversation — rejected: the checkpoint is a durable prompt prefix, so preserving a transient conversational register can amplify it across later compactions.
- Constrain the conversation model's language — rejected: the policy is for an internal checkpoint, not the user's visible conversation, and a conversation-wide rule would unnecessarily change normal interaction.
- Require ASCII-only output — rejected: ASCII is a character-set constraint rather than an engineering-register constraint and would unnecessarily distort legitimate literals and technical material.
- Append a separate final English-only sentence — rejected: stating the requirement in the instruction's opening output contract is shorter and ties it directly to the checkpoint being requested.
Consequences
- New checkpoints normalize narrative context into English while retaining the exact strings that future tool use and code work depend on.
- Existing checkpoint structure, compaction routing, and cache alignment are unchanged; only the final user instruction is different.
- The direct summarization call remains outside transcript snapshots because it emits no
assistant/chunkevents. The real-loop regression instead asserts the exact final instruction received by the summarization request.
中文
问题
压缩（compaction）检查点会成为下一次模型请求中持久存在的前缀。当多语言对话使压缩器以对话语言保留叙述性材料时，检查点可能引入大量代码、工具输出和既有推理（reasoning）前缀中均未出现的语言内容。该语言随后会在后续压缩周期中持续存在，并影响对话模型的推理文体。
决策
COMPACTION_INSTRUCTION 要求生成英语的内部工程检查点。它要求模型在必要时翻译叙述性源材料，同时保留精确的字面量；这包括路径、命令、错误、标识符、签名，以及精确性重要时的引用措辞。检查点的标题及简洁的工程项目符号仍沿用既有的结构化格式。
这项要求被整合到尾部压缩指令的第一句话中。回放的系统提示词、工具和对话历史与已路由请求保持字节级一致，因此该变更保留 压缩摘要前缀缓存说明 所确立的前缀缓存复用。
考虑过的替代方案
- 让回放的对话决定检查点语言——不采纳：检查点是持久的提示词前缀，保留短暂的对话文体可能在后续压缩中放大这种影响。
- 约束对话模型的语言——不采纳：该策略针对内部检查点，而不是用户可见的对话；对整个对话施加规则会不必要地改变正常交互。
- 要求仅输出 ASCII——不采纳：ASCII 是字符集约束，而非工程文体约束，并会不必要地扭曲合法的字面量和技术材料。
- 在末尾追加一句独立的仅限英语要求——不采纳：在指令开头的输出约定中说明该要求更简洁，也直接将其与所请求的检查点绑定。
后果
- 新检查点会将叙述性上下文规范化为英语，同时保留未来工具使用和代码工作所依赖的精确字符串。
- 既有检查点结构、压缩路由和缓存对齐保持不变；只有最后一条 user 指令不同。
- 直接摘要调用仍不纳入 transcript（文本记录）快照，因为它不会发出
assistant/chunk事件。真实循环回归改为断言摘要请求收到的精确最终指令。