fix(proxy): Kimi-provider-fix. inline local $ref siblings in chat tool parameters / 内联 chat 工具参数中携带 sibling 的本地 $ref

[hezhongtang]

中文

背景

Codex 客户端发送的工具定义中，会出现 JSON Schema $ref 携带 sibling 关键字的形式，例如 $defs 里的 {"$ref": "#/$defs/__schema2", "type": "string", "format": "uuid", "minLength": 1}。按 JSON Schema draft-07 及更早版本的语义，$ref 的 sibling 会被直接忽略；严格的 OpenAI 兼容上游（如 Kimi For Coding）会拒绝或静默丢弃这类 schema，导致工具参数校验异常。

同时，normalize_chat_tool_parameters 此前会无条件为 parameters 补 type / properties / required 默认值。当 parameters 本身是裸 $ref 时，补默认值反而人为制造了 $ref sibling。

改动

• parameters 为裸 $ref（对象仅含 $ref 一个键）时不再补 type / properties / required 默认值，避免人为制造 sibling
• 新增 inline_ref_siblings：递归遍历参数 schema，将携带 sibling 的本地 #/$defs/ 引用展开为目标定义的副本，sibling 键覆盖定义中的同名键
• 支持 $defs 别名链（裸 $ref 指向另一个 $ref），内置循环检测；一旦发现环，整体回退为原 schema，不做任何内联（行为由测试锚定）
• 保守保留：外部 URL 引用、未知本地引用、非对象定义目标均原样输出

测试

crates/codex-plus-core/tests/protocol_proxy.rs 新增 10 个测试，覆盖：sibling 内联与覆盖优先级、别名链解析顺序、嵌套 properties / items 中的引用、循环引用不死循环、外部 / 未知 / 非对象目标保留、裸 $ref 不再被补默认值等。

本地 cargo test -p codex-plus-core --test protocol_proxy 87/87 通过；cargo fmt --check 与 cargo clippy 对本次改动无新增告警。cargo test -p codex-plus-core 全量中仅 launcher 的 1 个用例在本机失败（a_busy_floating_helper_port_fails_immediately_without_waiting，改动未触及 launcher 代码，为预存问题）。

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English

Background

Tool definitions sent by the Codex client may contain JSON Schema $ref values carrying sibling keys, e.g. inside $defs: {"$ref": "#/$defs/__schema2", "type": "string", "format": "uuid", "minLength": 1}. Under JSON Schema draft-07 and earlier, siblings of $ref are ignored entirely; strict OpenAI-compatible upstreams (such as Kimi For Coding) reject or silently drop such schemas, which breaks tool-parameter validation.

In addition, normalize_chat_tool_parameters previously injected type / properties / required defaults unconditionally. When parameters itself is a bare $ref, those defaults create $ref siblings that never existed in the original schema.

Changes

• Bare $ref parameter schemas (objects whose only key is $ref) no longer receive synthetic type / properties / required defaults, so normalization never manufactures $ref siblings.
• New inline_ref_siblings: recursively walks the parameter schema and expands local #/$defs/ references that carry siblings into a copy of the resolved definition, with sibling keys overriding same-named definition keys.
• Supports alias chains inside $defs (a bare $ref pointing at another $ref) with cycle detection; if a cycle is found, the whole schema is returned untouched (behaviour pinned by tests).
• Conservative fallbacks: external URL references, unknown local names, and non-object definition targets are preserved as-is.

Testing

10 new tests in crates/codex-plus-core/tests/protocol_proxy.rs, covering: sibling inlining and override precedence, alias-chain resolution order, refs nested inside properties / items, cycle safety, preservation of external / unknown / non-object targets, and bare $ref schemas staying default-free.

Local cargo test -p codex-plus-core --test protocol_proxy passes 87/87; cargo fmt --check and cargo clippy report no new warnings for this change. In the full cargo test -p codex-plus-core run, one pre-existing launcher test fails on this machine (a_busy_floating_helper_port_fails_immediately_without_waiting); the change does not touch launcher code.