Files
OmniRoute/open-sse/translator/index.ts
Óscar Fonseca a3c3117254 fix(translator): preserve omitted subagent session IDs (#11297)
Validated on a 3-PR combined board: openai-responses-opencode-subagent-sessionid within the board's 20/20, typecheck:core + check:open-sse-typecheck clean, gates within baseline. Uses null as the omission sentinel for OpenCode's optional default-less subagent.sessionID under Responses/Codex strict mode (which required every declared property) — models can now omit the field to spawn a new child instead of inventing filler IDs; the null is stripped before OpenCode sees the call, real child IDs pass through unchanged. Thank you @ofonseca-pyming!
2026-08-23 21:03:16 -03:00

923 lines
37 KiB
TypeScript

import { FORMATS } from "./formats.ts";
import {
ensureToolCallIds,
fixMissingToolResponses,
stripOrphanedToolResults,
} from "./helpers/toolCallHelper.ts";
import {
NON_ANTHROPIC_THINKING_PLACEHOLDER,
prepareClaudeRequest,
} from "./helpers/claudeHelper.ts";
import { filterToOpenAIFormat } from "./helpers/openaiHelper.ts";
import {
providerHonorsOpenAIFormatCacheControl,
resolveConnectionCacheOverride,
} from "../utils/cacheControlPolicy.ts";
import { isInternalReasoningPlaceholder } from "../utils/reasoningPlaceholder.ts";
import {
coerceToolSchemas,
injectEmptyReasoningContentForToolCalls,
injectOptionalEnumOmissionForTools,
injectOptionalStringOmissionForTools,
sanitizeToolDescriptions,
} from "./helpers/schemaCoercion.ts";
import { getRequestTranslator, getResponseTranslator } from "./registry.ts";
import { bootstrapTranslatorRegistry } from "./bootstrap.ts";
import { hasThinkingConfig, normalizeThinkingConfig } from "../services/provider.ts";
import { applyThinkingBudget } from "../services/thinkingBudget.ts";
import { applyReasoningRuleDirective } from "@/lib/reasoningRouting/policy";
import { getModelPreserveVideoUrl } from "@/lib/db/models/modelPreserveVideoUrl";
import { getResolvedModelCapabilities, supportsReasoning } from "../services/modelCapabilities.ts";
import { normalizeRoles } from "../services/roleNormalizer.ts";
import { hoistLeadingSystemMessage } from "./helpers/strictSystemHoist.ts";
import {
buildAssistantMessageCacheKey,
lookupReasoning,
recordReplay,
requiresReasoningReplay,
} from "../services/reasoningCache.ts";
import {
normalizeResponsesReasoningEffort,
RESPONSES_STORE_MARKER,
} from "./request/openai-responses/helpers.ts";
bootstrapTranslatorRegistry();
export { register } from "./registry.ts";
function normalizeResponsesInputItem(item) {
if (typeof item === "string") {
return {
type: "message",
role: "user",
content: [{ type: "input_text", text: item }],
};
}
if (!item || typeof item !== "object") return item;
if (item.type || item.role) {
return item.type ? item : { type: "message", ...item };
}
if (typeof item.text === "string") {
return {
type: "message",
role: "user",
content: [{ type: "input_text", text: item.text }],
};
}
return item;
}
// Promote a stray top-level Chat-Completions-shaped `reasoning_effort` into the
// Responses-shaped `reasoning:{effort}` object, in place, removing the top-level key.
// No-op when `reasoning` is already present (an explicit Responses-shaped value always
// wins) or when `reasoning_effort` is absent.
//
// This exists for the SAME-FORMAT lane (source === target === OPENAI_RESPONSES), where
// translateRequest's hub-and-spoke translation block is skipped entirely (#7631): a
// caller that lands a top-level `reasoning_effort` there — e.g. applyNoThinkingAlias
// on the OpenAI path, which runs upstream of model-format resolution and cannot know
// yet whether the target lane is Responses-native — would otherwise reach the upstream
// with BOTH an unrecognized top-level field AND no `reasoning.effort`, so suppression
// silently does not take effect. The cross-format path (openai -> openai-responses)
// already performs the equivalent promotion in toResponses.ts; this covers the lane
// that promotion never runs on.
function promoteStrayReasoningEffort(body) {
if (!body || typeof body !== "object") return body;
if (body.reasoning !== undefined) return body;
if (body.reasoning_effort === undefined) return body;
const effort = normalizeResponsesReasoningEffort(body.reasoning_effort);
if (effort) {
body.reasoning = { effort };
}
delete body.reasoning_effort;
return body;
}
function normalizeOpenAIResponsesRequest(body) {
if (!body || typeof body !== "object") return body;
const normalized = promoteStrayReasoningEffort({ ...body });
// #10165 safety net: if a chat-shaped body reached Responses normalization
// without input, promote messages → input and map token/format fields.
if (normalized.input == null && Array.isArray(normalized.messages)) {
normalized.input = normalized.messages;
delete normalized.messages;
}
if (normalized.max_output_tokens == null) {
if (normalized.max_completion_tokens != null) {
normalized.max_output_tokens = normalized.max_completion_tokens;
delete normalized.max_completion_tokens;
} else if (normalized.max_tokens != null) {
normalized.max_output_tokens = normalized.max_tokens;
delete normalized.max_tokens;
}
} else {
delete normalized.max_tokens;
delete normalized.max_completion_tokens;
}
if (normalized.response_format != null && normalized.text == null) {
normalized.text = { format: normalized.response_format };
delete normalized.response_format;
} else if (normalized.response_format != null) {
delete normalized.response_format;
}
if (typeof normalized.input === "string") {
normalized.input = [
{
type: "message",
role: "user",
content: [{ type: "input_text", text: normalized.input }],
},
];
return normalized;
}
if (Array.isArray(normalized.input)) {
normalized.input = normalized.input.map(normalizeResponsesInputItem);
return normalized;
}
if (normalized.input && typeof normalized.input === "object") {
normalized.input = [normalizeResponsesInputItem(normalized.input)];
return normalized;
}
return normalized;
}
function hasNonEmptyReasoningContent(message: Record<string, unknown>): boolean {
return typeof message.reasoning_content === "string" && message.reasoning_content.length > 0;
}
function isReasoningOnlyReplayTarget(provider: unknown, model: unknown): boolean {
const normalizedProvider = String(provider ?? "")
.trim()
.toLowerCase();
const normalizedModel = String(model ?? "")
.trim()
.toLowerCase();
// DeepSeek V4 and Xiaomi MiMo both enforce "pass reasoning_content back on
// subsequent turns" even on PLAIN (non-tool-call) assistant turns. Without
// replaying on those turns the upstream 400s with "Param Incorrect: The
// reasoning_content in the thinking mode must be passed back to the API."
// (deepseek #1682, xiaomi-mimo 9router#1321/#1337).
return (
normalizedProvider === "deepseek" ||
/(^|\/)deepseek/i.test(normalizedModel) ||
normalizedProvider === "xiaomi-mimo" ||
/(^|\/)mimo/i.test(normalizedModel) ||
requiresReasoningReplay({
provider: normalizedProvider,
model: normalizedModel,
allowLegacyFallback: false,
})
);
}
/**
* Upstreams that reject an ABSENT reasoning_content on replay turns, so the
* placeholder must survive the cache miss.
*
* #9573/#9610 removed the placeholder globally because the model echoed it as
* its own reasoning and stopped (empty turns). That holds for DeepSeek, where
* an absent field was verified to be accepted — but Xiaomi MiMo still 400s
* ("Param Incorrect: The reasoning_content in the thinking mode must be passed
* back to the API", 9router#1321/#1337), so omitting the field there trades one
* live bug for another. Keep the placeholder only for those providers; the echo
* that comes back is still stripped on the way in by
* isInternalReasoningPlaceholder(), so it never re-poisons cache or history.
*/
function requiresReasoningContentPresence(provider: unknown, model: unknown): boolean {
const normalizedProvider = String(provider ?? "")
.trim()
.toLowerCase();
const normalizedModel = String(model ?? "")
.trim()
.toLowerCase();
return normalizedProvider === "xiaomi-mimo" || /(^|\/)mimo/i.test(normalizedModel);
}
type OpenAIReplayOptions = {
canReplayReasoningOnly: boolean;
requiresExplicitReasoningReplay: boolean;
provider: string;
model: string;
reasoningCacheScope?: string | null;
};
function replayOpenAIReasoningMessage(
messages: Array<Record<string, unknown>>,
messageIndex: number,
options: OpenAIReplayOptions
): void {
const message = messages[messageIndex];
if (!message || message.role !== "assistant") return;
// Moonshot `partial` messages are output prefixes, not completed prior turns.
if (message.partial === true) {
if (message.reasoning_content === "") delete message.reasoning_content;
return;
}
if (
!hasNonEmptyReasoningContent(message) &&
typeof message.reasoning === "string" &&
message.reasoning.trim().length > 0
) {
message.reasoning_content = message.reasoning;
}
const toolCalls = Array.isArray(message.tool_calls) ? message.tool_calls : [];
const hasToolCalls = toolCalls.length > 0;
const shouldReplayReasoningOnly =
!hasToolCalls && options.canReplayReasoningOnly && !hasNonEmptyReasoningContent(message);
if (!hasToolCalls && !shouldReplayReasoningOnly) {
if (
message.reasoning_content === "" ||
isInternalReasoningPlaceholder(message.reasoning_content)
) {
delete message.reasoning_content;
}
return;
}
if (hasNonEmptyReasoningContent(message)) {
if (!isInternalReasoningPlaceholder(message.reasoning_content)) return;
delete message.reasoning_content;
}
const firstToolCall =
toolCalls[0] && typeof toolCalls[0] === "object" && !Array.isArray(toolCalls[0])
? (toolCalls[0] as Record<string, unknown>)
: null;
const cacheKey = hasToolCalls
? typeof firstToolCall?.id === "string"
? firstToolCall.id
: ""
: buildAssistantMessageCacheKey(options.reasoningCacheScope, messages, messageIndex);
if (cacheKey) {
const cached = lookupReasoning(cacheKey);
if (cached) {
message.reasoning_content = cached;
recordReplay();
return;
}
}
if (options.requiresExplicitReasoningReplay) {
if (message.reasoning_content === "") delete message.reasoning_content;
return;
}
if ((hasToolCalls || shouldReplayReasoningOnly) && !message.reasoning_content) {
if (requiresReasoningContentPresence(options.provider, options.model)) {
message.reasoning_content = NON_ANTHROPIC_THINKING_PLACEHOLDER;
} else {
delete message.reasoning_content;
}
}
}
/** @param options.normalizeToolCallId - When true, use 9-char tool call ids (e.g. Mistral); when false, leave ids as-is */
/** @param options.preserveDeveloperRole - undefined/true: keep developer for OpenAI format (default); false: map to system */
/** @param options.preserveCacheControl - When true, preserve client-side cache_control markers (for Claude Code, etc.) */
// Translate request: source -> openai -> target
// Client-only assistant "echo" fields that strict OpenAI-compatible upstreams (e.g.
// Mistral) reject with 422 extra_forbidden when sent back as input history. They carry
// no value upstream and are dropped on the OpenAI target path (#1649). `audio` is
// deliberately NOT included: OpenAI audio models reference a prior assistant audio
// response by id on multi-turn, so stripping it would break that (Mistral never emits
// audio, so it is never present there).
const OPENAI_INCOMPATIBLE_ECHO_FIELDS = [
"reasoning_content",
"reasoning",
"refusal",
"annotations",
"cache_control",
];
export function translateRequest(
sourceFormat,
targetFormat,
model,
body,
stream = true,
credentials = null,
provider = null,
reqLogger = null,
options?: {
normalizeToolCallId?: boolean;
preserveDeveloperRole?: boolean;
preserveCacheControl?: boolean;
signatureNamespace?: string | null;
preCompressionBody?: Record<string, unknown> | null;
reasoningCacheScope?: string | null;
/** UA-detected GitHub Copilot client. Forwarded to translators via the
* transient `_copilotClient` credential flag (see openai-responses → openai). */
copilotClient?: boolean;
}
) {
let result = body;
const use9CharId = options?.normalizeToolCallId === true;
const preserveDeveloperRole = options?.preserveDeveloperRole;
const connectionCacheOverride = resolveConnectionCacheOverride(
(credentials as { providerSpecificData?: unknown } | null)?.providerSpecificData
);
const normalizedProvider = String(provider ?? "");
const normalizedModel = String(model ?? "");
const isKimiCoding =
normalizedProvider === "kimi-coding" || normalizedProvider === "kimi-coding-apikey";
// GLM-family upstreams (Z.AI / Zhipu console gateways) reject messages arrays
// with no role:"user" turn (400 [1214] "The messages parameter is illegal").
// Pure tool-loop continuations from coding agents produce exactly that shape
// after Claude→OpenAI conversion, so flag those providers to have the source→
// openai translator append a synthetic user turn when none survives.
const isGlmFamilyUpstream =
["opencode-go", "opencode-zen"].includes(normalizedProvider) ||
/glm|zhipu|z-ai/i.test(normalizedModel);
// Phase 2: Apply thinking budget control before normalization
result = applyThinkingBudget(result);
// Explicit reasoning-routing policies are final. The marker is internal and is
// consumed here before any provider translation can see it.
result = applyReasoningRuleDirective(result);
// Normalize thinking config: remove if lastMessage is not user
normalizeThinkingConfig(result);
// Resolve the replay contract before Responses input is converted: conversion
// must know whether reasoning items are protocol history rather than display metadata.
const resolvedCapabilities = getResolvedModelCapabilities({
provider: normalizedProvider,
model: normalizedModel,
});
const replayRequirements = {
provider: normalizedProvider,
model: normalizedModel,
thinkingEnabled: hasThinkingConfig(result),
supportsReasoning: supportsReasoning({
provider: normalizedProvider,
model: normalizedModel,
}),
interleavedField: resolvedCapabilities?.interleavedField ?? null,
};
const isReasoner = requiresReasoningReplay(replayRequirements);
const requiresExplicitReasoningReplay = requiresReasoningReplay({
...replayRequirements,
allowLegacyFallback: false,
});
const preserveResponsesReasoning = sourceFormat === FORMATS.OPENAI_RESPONSES && isReasoner;
// Ensure tool_calls have id; optionally normalize to 9-char for providers like Mistral
ensureToolCallIds(result, { use9CharId });
// Fix missing tool responses (insert empty tool_result if needed)
fixMissingToolResponses(result);
// Claude reconciliation preserves orphaned tool output as labelled user text.
// Keep the raw result carriers until the target translator can perform that
// lossless conversion; other target formats retain the strict orphan filter.
if (targetFormat !== FORMATS.CLAUDE) {
stripOrphanedToolResults(result);
}
// Normalize roles: developer→system unless preserved, system→user for incompatible models.
// This handles (1) sourceFormat openai with messages containing developer → non-openai target
// or preserveDeveloperRole=false, and (2) all other paths where result.messages already exists.
if (result.messages && Array.isArray(result.messages)) {
result.messages = normalizeRoles(
result.messages,
provider || "",
model || "",
targetFormat,
preserveDeveloperRole
);
}
// #7293: hoist any system message at index > 0 onto index 0 for providers that reject
// a non-first system role (systemMessageMustBeFirst() — same source of truth as the
// memory-injection half, #6135/PR#6225). Runs for every path — including same-format
// (OpenAI→OpenAI) passthrough, where none of the format-specific translators below
// execute — so a client-injected mid-array system message (OpenCode/Kilo Code style
// clients) is still normalized before reaching the upstream. No-op for non-strict
// providers and for already-compliant requests (prompt-cache prefix stability).
if (targetFormat === FORMATS.OPENAI && result.messages && Array.isArray(result.messages)) {
result.messages = hoistLeadingSystemMessage(result.messages, provider);
}
if (
sourceFormat === FORMATS.OPENAI &&
targetFormat === FORMATS.OPENAI_RESPONSES &&
isReasoner &&
Array.isArray(result.messages)
) {
const messages = result.messages as Array<Record<string, unknown>>;
const replayOptions: OpenAIReplayOptions = {
canReplayReasoningOnly: isReasoningOnlyReplayTarget(normalizedProvider, normalizedModel),
requiresExplicitReasoningReplay,
provider: normalizedProvider,
model: normalizedModel,
reasoningCacheScope: options?.reasoningCacheScope,
};
for (let messageIndex = 0; messageIndex < messages.length; messageIndex += 1) {
replayOpenAIReasoningMessage(messages, messageIndex, replayOptions);
}
}
// If same format, skip translation steps
if (sourceFormat !== targetFormat) {
// Check for direct translation path first (e.g., Claude → Gemini)
const directTranslator = getRequestTranslator(sourceFormat, targetFormat);
if (directTranslator && sourceFormat !== FORMATS.OPENAI && targetFormat !== FORMATS.OPENAI) {
// Thread the routed provider id so target translators can apply provider-specific
// quirks (e.g. Vertex rejects function_call.id — #3440).
// Also thread signatureNamespace so Claude→Gemini can re-attach cached
// thoughtSignature on tool-use history (#8979 / #2504 parity with the hub path).
const hasNs = options?.signatureNamespace != null;
const hasProvider = provider != null;
const directCredentials =
hasNs || hasProvider
? {
...(credentials && typeof credentials === "object" ? credentials : {}),
...(hasProvider ? { _provider: provider } : {}),
...(hasNs ? { _signatureNamespace: options.signatureNamespace } : {}),
}
: credentials;
result = directTranslator(model, result, stream, directCredentials);
} else {
// Fallback: hub-and-spoke via OpenAI
// Step 1: source -> openai (if source is not openai)
if (sourceFormat !== FORMATS.OPENAI) {
const toOpenAI = getRequestTranslator(sourceFormat, FORMATS.OPENAI);
if (toOpenAI) {
// Forward Copilot UA marker to source→openai translators only.
const hasTargetHint = targetFormat != null;
// #2069 — forward the cache_control-preservation intent so the
// source→openai translator (e.g. claudeToOpenAIRequest) keeps the
// client's breakpoints — but ONLY for providers that honor explicit
// OpenAI-format cache_control (DashScope/alibaba, Xiaomi MiMo). Generic
// / implicit-cache OpenAI providers (openai/codex/azure) must still be
// stripped.
const preserveCacheControl =
options?.preserveCacheControl === true &&
providerHonorsOpenAIFormatCacheControl(provider, connectionCacheOverride);
const step1Credentials =
options?.copilotClient ||
hasTargetHint ||
preserveCacheControl ||
preserveResponsesReasoning ||
isGlmFamilyUpstream
? {
...(credentials && typeof credentials === "object" ? credentials : {}),
...(options?.copilotClient ? { _copilotClient: true } : {}),
...(hasTargetHint ? { _targetFormat: targetFormat } : {}),
...(preserveCacheControl ? { _preserveCacheControl: true } : {}),
...(preserveResponsesReasoning ? { _preserveReasoningContent: true } : {}),
...(isGlmFamilyUpstream ? { _ensureUserTurn: true } : {}),
}
: credentials;
result = toOpenAI(model, result, stream, step1Credentials);
// Log OpenAI intermediate format
reqLogger?.logOpenAIRequest?.(result);
}
}
// Step 2: openai -> target (if target is not openai)
if (targetFormat !== FORMATS.OPENAI) {
const fromOpenAI = getRequestTranslator(FORMATS.OPENAI, targetFormat);
if (fromOpenAI) {
const hasNs = options?.signatureNamespace != null;
const hasPreCompression = options?.preCompressionBody != null;
const hasCopilot = options?.copilotClient === true;
const hasProvider = provider != null;
const translationCredentials =
hasNs || hasPreCompression || hasCopilot || hasProvider
? {
...(credentials && typeof credentials === "object" ? credentials : {}),
...(hasNs ? { _signatureNamespace: options.signatureNamespace } : {}),
...(hasPreCompression ? { _preCompressionBody: options.preCompressionBody } : {}),
...(hasCopilot ? { _copilotClient: true } : {}),
// Routed provider id so target translators can apply provider-specific
// quirks (e.g. Vertex rejects function_call.id — #3440).
...(hasProvider ? { _provider: provider } : {}),
}
: credentials;
// #9780 — carry the Responses namespace identity map across the pivot.
// Target translators return a brand-new object (buildKiroPayload et
// al.), dropping the non-enumerable property step 1 attached; the
// #7936 seam then gets null and namespace sub-tool calls come back
// flattened, which Codex rejects with `unsupported call: <name>`.
const identityMap = (result as Record<string, unknown>)._namespaceToolIdentityMap;
const translated = fromOpenAI(model, result, stream, translationCredentials);
if (
identityMap instanceof Map &&
translated &&
typeof translated === "object" &&
!((translated as Record<string, unknown>)._namespaceToolIdentityMap instanceof Map)
) {
Object.defineProperty(translated, "_namespaceToolIdentityMap", {
value: identityMap,
enumerable: false,
configurable: true,
writable: true,
});
}
result = translated;
}
}
}
}
// Always normalize to clean OpenAI format when target is OpenAI
// This handles hybrid requests (e.g., OpenAI messages + Claude tools)
if (targetFormat === FORMATS.OPENAI) {
// #2069 — preserve client cache_control breakpoints only for providers that
// honor explicit OpenAI-format markers (DashScope/alibaba, Xiaomi MiMo) when
// requested upstream; generic/implicit-cache OpenAI providers stay stripped.
result = filterToOpenAIFormat(result, {
preserveCacheControl:
options?.preserveCacheControl === true &&
providerHonorsOpenAIFormatCacheControl(provider, connectionCacheOverride),
// #4849 regression guard: keep client reasoning_content for replay providers.
preserveReasoningContent: isReasoner,
// Per-provider/model preserveVideoUrl flag from compat overrides.
// Falls back to true for moonshot/kimi when unset (legacy behavior).
preserveVideoUrl:
getModelPreserveVideoUrl(normalizedProvider, normalizedModel) ??
(normalizedProvider === "moonshot" || normalizedProvider === "kimi"),
});
}
// Final step: prepare request for Claude format endpoints
// Preserve cache_control when:
// 1. Claude passthrough mode (Claude → Claude), OR
// 2. Explicitly requested via options (for caching-aware clients like Claude Code)
// When preserve-mode has nothing to preserve (the client sent no cache_control
// anywhere), fall back to the standard heuristic so the request never ships
// with zero prompt-cache breakpoints. Translator-path only — the CC relay
// path keeps its "never supplement" contract.
if (targetFormat === FORMATS.CLAUDE) {
const isClaudePassthrough = sourceFormat === FORMATS.CLAUDE;
const preserveCache = isClaudePassthrough || options?.preserveCacheControl === true;
result = prepareClaudeRequest(result, provider, preserveCache, model, {
fallbackToHeuristicWhenNoMarkers: true,
});
}
// Normalize openai-responses input shape for providers that require list input.
if (targetFormat === FORMATS.OPENAI_RESPONSES) {
result = normalizeOpenAIResponsesRequest(result);
}
// Second role normalization: only for OPENAI_RESPONSES. Here messages are built from input
// after the translation step, so the first normalizeRoles (above) did not see them. For
// sourceFormat openai with messages already on the body, the first block handles developer
// → system (non-openai target or preserveDeveloperRole=false); no second pass needed.
if (
sourceFormat === FORMATS.OPENAI_RESPONSES &&
result.messages &&
Array.isArray(result.messages)
) {
result.messages = normalizeRoles(
result.messages,
provider || "",
model || "",
targetFormat,
preserveDeveloperRole
);
}
if (result.tools !== undefined) {
// Plain-string omission must run before coerceToolSchemas() strips `default`,
// so defaulted optional strings stay unsentinelled. Enum injection stays after
// coercion to preserve the #7023 pipeline.
if (targetFormat === FORMATS.OPENAI_RESPONSES) {
result.tools = injectOptionalStringOmissionForTools(result.tools);
}
result.tools = coerceToolSchemas(result.tools);
result.tools = sanitizeToolDescriptions(result.tools);
if (targetFormat === FORMATS.OPENAI_RESPONSES) {
result.tools = injectOptionalEnumOmissionForTools(result.tools);
}
}
if (
targetFormat === FORMATS.OPENAI &&
!requiresExplicitReasoningReplay &&
result.messages &&
Array.isArray(result.messages)
) {
result.messages = injectEmptyReasoningContentForToolCalls(result.messages, provider, model);
}
// Ensure unique tool_call ids on final payload (translators may have introduced duplicates)
ensureToolCallIds(result, { use9CharId });
fixMissingToolResponses(result);
stripOrphanedToolResults(result);
if (result.tools) {
result.tools = coerceToolSchemas(result.tools);
result.tools = sanitizeToolDescriptions(result.tools);
}
// Reasoning Replay Cache (#1628): Re-inject cached reasoning_content for
// thinking-mode models (DeepSeek V4, Kimi K2, Qwen-Thinking, etc.) when
// clients omit it from the conversation history. Without this, DeepSeek V4
// returns 400: "The reasoning_content in the thinking mode must be passed
// back to the API."
// isReasoner / normalizedProvider / normalizedModel / resolvedCapabilities were
// resolved up-front (before the OpenAI-format filter) so the #4849 reasoning strip
// could honor reasoning-replay providers.
if (isReasoner && result.messages && Array.isArray(result.messages)) {
const canReplayReasoningOnly = isReasoningOnlyReplayTarget(normalizedProvider, normalizedModel);
for (const [messageIndex, msg] of result.messages.entries()) {
if (msg.role !== "assistant") continue;
// Moonshot `partial` messages are output prefixes, not completed prior
// assistant turns. Never attach replayed or placeholder reasoning to them.
if (msg.partial === true) {
if (msg.reasoning_content === "") delete msg.reasoning_content;
continue;
}
// Detect tool calls in either format
const hasToolCalls = Array.isArray(msg.tool_calls) && msg.tool_calls.length > 0;
// Claude format: tool_use lives in content[] blocks, not msg.tool_calls
const hasToolUseBlocks =
!hasToolCalls &&
Array.isArray(msg.content) &&
msg.content.some((b) => b?.type === "tool_use");
// For DeepSeek replay targets, a plain (non-tool-call) assistant turn must
// ALSO carry reasoning_content in thinking mode, or DeepSeek V4+ returns 400:
// "The reasoning_content in the thinking mode must be passed back to the API."
// Enter the replay path when the field is MISSING or empty (#1682) — not only
// when it is already present (the previous gate only matched messages that
// already had the field, so stripped-history turns from clients like Cursor
// were skipped and forwarded without reasoning_content).
const shouldReplayReasoningOnly =
!hasToolCalls &&
!hasToolUseBlocks &&
canReplayReasoningOnly &&
!hasNonEmptyReasoningContent(msg);
if (!hasToolCalls && !hasToolUseBlocks && !shouldReplayReasoningOnly) {
// Strip empty or placeholder reasoning_content on non-tool-call messages
// we are NOT replaying. The placeholder is request scaffolding, never
// real reasoning — forwarding it makes the model continue its chain of
// thought FROM that text (echo → empty stop, #9573).
if (msg.reasoning_content === "" || isInternalReasoningPlaceholder(msg.reasoning_content)) {
delete msg.reasoning_content;
}
continue;
}
if (hasToolUseBlocks) {
// ── Claude-format message ──
// Has tool_use blocks but no thinking block yet.
// Reasoning models (Kimi K2, etc.) require a thinking block before tool_use
// on multi-turn or they regenerate the same tool call infinitely.
const thinkingBlock = msg.content.find(
(b) => b?.type === "thinking" || b?.type === "redacted_thinking"
);
const hasNonEmptyClientThinking =
thinkingBlock?.type === "thinking" &&
typeof thinkingBlock.thinking === "string" &&
thinkingBlock.thinking.trim().length > 0;
if (thinkingBlock && (!isKimiCoding || hasNonEmptyClientThinking)) continue;
const toolUseBlocks = msg.content.filter((b) => b?.type === "tool_use");
const firstToolUseId = toolUseBlocks[0]?.id;
const firstToolUseIdx = msg.content.findIndex((b) => b?.type === "tool_use");
// Client reasoning wins above. Otherwise try authentic replay before
// retaining Kimi Code's empty protocol marker as the final fallback.
if (firstToolUseId) {
const cached = lookupReasoning(firstToolUseId);
if (cached) {
if (thinkingBlock) {
thinkingBlock.type = "thinking";
thinkingBlock.thinking = cached;
delete thinkingBlock.data;
delete thinkingBlock.signature;
} else {
msg.content.splice(firstToolUseIdx, 0, {
type: "thinking",
thinking: cached,
});
}
recordReplay();
continue;
}
}
if (isKimiCoding) {
if (thinkingBlock) {
thinkingBlock.type = "thinking";
thinkingBlock.thinking = "";
delete thinkingBlock.data;
delete thinkingBlock.signature;
} else {
msg.content.splice(firstToolUseIdx, 0, { type: "thinking", thinking: "" });
}
continue;
}
if (requiresExplicitReasoningReplay) continue;
msg.content.splice(firstToolUseIdx, 0, {
type: "thinking",
thinking: NON_ANTHROPIC_THINKING_PLACEHOLDER,
});
continue;
}
// ── OpenAI-format message ──
replayOpenAIReasoningMessage(result.messages, messageIndex, {
canReplayReasoningOnly,
requiresExplicitReasoningReplay,
provider: normalizedProvider,
model: normalizedModel,
reasoningCacheScope: options?.reasoningCacheScope,
});
}
} else if (
!isReasoner &&
targetFormat === FORMATS.OPENAI &&
result.messages &&
Array.isArray(result.messages)
) {
for (const msg of result.messages) {
for (const field of OPENAI_INCOMPATIBLE_ECHO_FIELDS) {
if (msg[field] !== undefined) {
delete msg[field];
}
}
}
}
// #<store-marker-leak>: a Responses-source request stashes the client's
// `store` intent under this internal marker (see the Responses -> OpenAI
// step above) so a later OpenAI -> Responses re-conversion can restore it
// as `store`. When the destination stays in Chat Completions shape (no
// such re-conversion happens), nothing else consumes the marker, and it
// was leaking verbatim into the real upstream request body — e.g. OpenAI
// itself rejects it with "Unknown parameter: '_omnirouteResponsesStore'".
// Always drop it here: any handler that still needs the client's original
// `store` value would have already read the marker before this point.
if (RESPONSES_STORE_MARKER in result) {
delete result[RESPONSES_STORE_MARKER];
}
// #7293 follow-up: the pre-translation hoist above normalizes the *source*
// message array, which a target translator can then undo. `claudeToOpenAI`
// pushes `body.system` as a fresh leading system message before appending the
// converted messages, so an already-hoisted system lands at index 1 again;
// a Responses-source request has no `messages` at all until translation, so
// the earlier call is a no-op for it. Re-run on the final outbound array —
// it is the only shape the upstream actually sees. Idempotent: same array
// reference for non-strict providers and already-compliant requests, so
// prompt-cache prefixes stay stable.
if (targetFormat === FORMATS.OPENAI && result.messages && Array.isArray(result.messages)) {
result.messages = hoistLeadingSystemMessage(result.messages, provider);
}
return result;
}
// Translate response chunk: target -> openai -> source
export function translateResponse(targetFormat, sourceFormat, chunk, state) {
// If same format, return as-is — but never propagate the null/flush signal as a
// literal `[null]`, which leaks an empty `data: null` SSE event between chunks and
// crashes strict clients (#1052).
if (sourceFormat === targetFormat) {
return chunk == null ? [] : [chunk];
}
let results = [chunk];
let openaiResults = null; // Store OpenAI intermediate results
// Check for direct translation path first (e.g., Gemini → Claude)
const directTranslator = getResponseTranslator(targetFormat, sourceFormat);
if (directTranslator && targetFormat !== FORMATS.OPENAI && sourceFormat !== FORMATS.OPENAI) {
const converted = directTranslator(chunk, state);
if (converted) {
results = Array.isArray(converted) ? converted : [converted];
} else {
results = [];
}
return results;
}
// Fallback: hub-and-spoke via OpenAI
// Step 1: target -> openai (if target is not openai)
if (targetFormat !== FORMATS.OPENAI) {
const toOpenAI = getResponseTranslator(targetFormat, FORMATS.OPENAI);
if (toOpenAI) {
results = [];
const converted = toOpenAI(chunk, state);
if (converted) {
results = Array.isArray(converted) ? converted : [converted];
openaiResults = results; // Store OpenAI intermediate
}
}
}
// Step 2: openai -> source (if source is not openai)
if (sourceFormat !== FORMATS.OPENAI) {
const fromOpenAI = getResponseTranslator(FORMATS.OPENAI, sourceFormat);
if (fromOpenAI) {
const finalResults = [];
for (const r of results) {
const converted = fromOpenAI(r, state);
if (converted) {
finalResults.push(...(Array.isArray(converted) ? converted : [converted]));
}
}
// Flush: pass null to source-format translator even when Step 1 produced no output.
// This is critical for formats like openai-responses that emit terminal events
// (e.g., response.completed with total_tokens) in their flush handler.
if (chunk === null && results.length === 0) {
const converted = fromOpenAI(null, state);
if (converted) {
finalResults.push(...(Array.isArray(converted) ? converted : [converted]));
}
}
results = finalResults;
}
}
// Attach OpenAI intermediate results for logging
if (openaiResults && sourceFormat !== FORMATS.OPENAI && targetFormat !== FORMATS.OPENAI) {
(results as { _openaiIntermediate?: unknown })._openaiIntermediate = openaiResults;
}
return results;
}
// Check if translation needed
export function needsTranslation(sourceFormat, targetFormat) {
return sourceFormat !== targetFormat;
}
// Initialize state for streaming response based on format
export function initState(sourceFormat) {
// Base state for all formats
const base = {
messageId: null,
model: null,
textBlockStarted: false,
thinkingBlockStarted: false,
inThinkingBlock: false,
currentBlockIndex: null,
toolCalls: new Map(),
finishReason: null,
finishReasonSent: false,
usage: null,
contentBlockIndex: -1,
};
// Add openai-responses specific fields
if (sourceFormat === FORMATS.OPENAI_RESPONSES) {
return {
...base,
seq: 0,
responseId: `resp_${Date.now()}`,
created: Math.floor(Date.now() / 1000),
started: false,
msgTextBuf: {},
msgItemAdded: {},
msgContentAdded: {},
msgItemDone: {},
reasoningId: "",
reasoningIndex: -1,
reasoningBuf: "",
reasoningPartAdded: false,
reasoningDone: false,
inThinking: false,
parseTextualReasoningTags: false,
funcArgsBuf: {},
funcArgsEscapeState: {},
funcNames: {},
funcCallIds: {},
funcArgsDone: {},
funcItemAdded: {},
funcItemDone: {},
completedOutputItems: [],
completedSent: false,
};
}
return base;
}
// Initialize all translators (no-op, kept for backward compatibility)
export function initTranslators() {
bootstrapTranslatorRegistry();
}