refactor(providers): split buildPrompt + extract applyCliDefaults to keep complexity under ratchet (#6220) (#5997)

open-sse/executors/gitlab.ts

@@ -91,79 +91,74 @@ function extractTextContent(content: unknown): string {
  * re-emitting the same `<tool>` call forever (#6220). Complements the tool_call emission
  * added in #6051.
  */
-export function buildPrompt(messages: OpenAIMessage[] | undefined): string {
-  if (!Array.isArray(messages)) return "";
-
-  const hasToolExchange = messages.some((message) => {
+function hasToolExchange(messages: OpenAIMessage[]): boolean {
+  return messages.some((message) => {
     const role = String(message?.role || "user").toLowerCase();
     if (role === "tool") return true;
     return (
-      role === "assistant" &&
-      Array.isArray(message?.tool_calls) &&
-      message.tool_calls.length > 0
+      role === "assistant" && Array.isArray(message?.tool_calls) && message.tool_calls.length > 0
     );
   });
+}
 
+/** Legacy flatten: system instructions + the latest user message. */
+function buildSimplePrompt(messages: OpenAIMessage[]): string {
   const systemParts: string[] = [];
-
-  if (!hasToolExchange) {
-    // Legacy path — unchanged: system instructions + the latest user message.
-    const userParts: string[] = [];
-    for (const message of messages) {
-      const role = String(message?.role || "user").toLowerCase();
-      const text = extractTextContent(message?.content);
-      if (!text) continue;
-      if (role === "system" || role === "developer") {
-        systemParts.push(text);
-        continue;
-      }
-      if (role === "user") {
-        userParts.push(text);
-      }
+  const userParts: string[] = [];
+  for (const message of messages) {
+    const role = String(message?.role || "user").toLowerCase();
+    const text = extractTextContent(message?.content);
+    if (!text) continue;
+    if (role === "system" || role === "developer") {
+      systemParts.push(text);
+    } else if (role === "user") {
+      userParts.push(text);
     }
-    const latestUserPrompt = userParts.at(-1) || "";
-    if (!systemParts.length) {
-      return latestUserPrompt;
-    }
-    return `System instructions:\n${systemParts.join("\n\n")}\n\n${latestUserPrompt}`.trim();
   }
+  const latestUserPrompt = userParts.at(-1) || "";
+  if (!systemParts.length) return latestUserPrompt;
+  return `System instructions:\n${systemParts.join("\n\n")}\n\n${latestUserPrompt}`.trim();
+}
 
-  // Tool-exchange path — serialize the full turn history so the model sees the tool
-  // result and continues instead of repeating the tool call (#6220).
+/** Render an assistant turn (its text plus any tool calls) for the tool-exchange prompt. */
+function renderAssistantTurn(message: OpenAIMessage, text: string): string | null {
+  const lines: string[] = [];
+  if (text) lines.push(text);
+  for (const tc of Array.isArray(message?.tool_calls) ? message.tool_calls : []) {
+    const id = tc?.id ? ` [${tc.id}]` : "";
+    lines.push(
+      `Called tool ${tc?.function?.name || "tool"}${id} with arguments: ${tc?.function?.arguments ?? ""}`
+    );
+  }
+  return lines.length ? `Assistant: ${lines.join("\n")}` : null;
+}
+
+/** Render one message as a labeled conversation line for the tool-exchange prompt. */
+function renderConversationTurn(message: OpenAIMessage, role: string, text: string): string | null {
+  if (role === "user") return text ? `User: ${text}` : null;
+  if (role === "assistant") return renderAssistantTurn(message, text);
+  if (role === "tool") {
+    const id = message?.tool_call_id ? ` for ${message.tool_call_id}` : "";
+    const name = message?.name ? ` (${message.name})` : "";
+    return `Tool result${name}${id}: ${text}`;
+  }
+  return null;
+}
+
+/** Serialize the full turn history so the model sees the tool result (#6220). */
+function buildToolExchangePrompt(messages: OpenAIMessage[]): string {
+  const systemParts: string[] = [];
   const convo: string[] = [];
   for (const message of messages) {
     const role = String(message?.role || "user").toLowerCase();
     const text = extractTextContent(message?.content);
-
     if (role === "system" || role === "developer") {
       if (text) systemParts.push(text);
       continue;
     }
-    if (role === "user") {
-      if (text) convo.push(`User: ${text}`);
-      continue;
-    }
-    if (role === "assistant") {
-      const lines: string[] = [];
-      if (text) lines.push(text);
-      const toolCalls = Array.isArray(message?.tool_calls) ? message.tool_calls : [];
-      for (const tc of toolCalls) {
-        const name = tc?.function?.name || "tool";
-        const args = tc?.function?.arguments ?? "";
-        const id = tc?.id ? ` [${tc.id}]` : "";
-        lines.push(`Called tool ${name}${id} with arguments: ${args}`);
-      }
-      if (lines.length) convo.push(`Assistant: ${lines.join("\n")}`);
-      continue;
-    }
-    if (role === "tool") {
-      const id = message?.tool_call_id ? ` for ${message.tool_call_id}` : "";
-      const name = message?.name ? ` (${message.name})` : "";
-      convo.push(`Tool result${name}${id}: ${text}`);
-      continue;
-    }
+    const line = renderConversationTurn(message, role, text);
+    if (line) convo.push(line);
   }
-
   const header = systemParts.length
     ? `System instructions:\n${systemParts.join("\n\n")}\n\n`
     : "";
@@ -172,6 +167,20 @@ export function buildPrompt(messages: OpenAIMessage[] | undefined): string {
   )}\n\nContinue the response using the tool result above; do not repeat the tool call.`.trim();
 }
 
+/**
+ * GitLab code_suggestions is a single-prompt completion API (no chat roles), so the
+ * OpenAI message array must be flattened to text. Simple conversations keep the legacy
+ * shape; a tool exchange (assistant `tool_calls` or a `tool` result) serializes the full
+ * conversation so the model continues instead of re-emitting the same `<tool>` call
+ * forever (#6220). Complements the tool_call emission added in #6051.
+ */
+export function buildPrompt(messages: OpenAIMessage[] | undefined): string {
+  if (!Array.isArray(messages)) return "";
+  return hasToolExchange(messages)
+    ? buildToolExchangePrompt(messages)
+    : buildSimplePrompt(messages);
+}
+
 function toOpenAIError(status: number, message: string): Response {
   return new Response(
     JSON.stringify({

open-sse/utils/opencodeHeaders.ts

@@ -75,22 +75,24 @@ export function forwardOpencodeClientHeaders(
 
   // 4. OpencodeExecutor-only: synthesize the OpenCode CLI identity Cloudflare expects
   //    on VPS egress, for any key the client did not supply (#5997).
-  const cliDefaults = options?.cliDefaults;
-  if (cliDefaults) {
-    if (!headers["User-Agent"] && !headers["user-agent"]) {
-      setUserAgentHeader(headers, cliDefaults.userAgent);
-    }
-    if (!headers["x-opencode-client"]) {
-      headers["x-opencode-client"] = cliDefaults.client;
-    }
-    if (!headers["x-opencode-project"]) {
-      headers["x-opencode-project"] = cliDefaults.project;
-    }
-    if (!headers["x-opencode-request"]) {
-      headers["x-opencode-request"] = randomUUID();
-    }
-    if (!headers["x-opencode-session"]) {
-      headers["x-opencode-session"] = randomUUID();
-    }
+  if (options?.cliDefaults) {
+    applyCliDefaults(headers, options.cliDefaults);
   }
 }
+
+/**
+ * Fill the OpenCode CLI identity headers Cloudflare requires on VPS egress, but only for
+ * keys the client did not already supply (client values always win). (#5997)
+ */
+function applyCliDefaults(
+  headers: Record<string, string>,
+  cliDefaults: { userAgent: string; client: string; project: string }
+): void {
+  if (!headers["User-Agent"] && !headers["user-agent"]) {
+    setUserAgentHeader(headers, cliDefaults.userAgent);
+  }
+  headers["x-opencode-client"] ||= cliDefaults.client;
+  headers["x-opencode-project"] ||= cliDefaults.project;
+  headers["x-opencode-request"] ||= randomUUID();
+  headers["x-opencode-session"] ||= randomUUID();
+}