injection guide comments

Author: Tarquinen

lib/messages/inject.ts

@@ -193,14 +193,18 @@ export const insertPruneToolContext = (
         (msg) => !(msg.info.role === "user" && isIgnoredUserMessage(msg)),
     )
 
-    // It's not safe to inject assistant role messages following a user message, as models such
+    // It's not safe to inject assistant role messages following a user message as models such
     // as Claude expect the assistant "turn" to start with reasoning parts. Reasoning parts in many
     // cases also cannot be faked as they may be encrypted by the model.
+    // Gemini only accepts synth reasoning text if it is "skip_thought_signature_validator"
     if (!lastNonIgnoredMessage || lastNonIgnoredMessage.info.role === "user") {
         messages.push(createSyntheticUserMessage(lastUserMessage, combinedContent, variant))
     } else {
-        // For DeepSeek and Kimi, append tool part to existing message, it seems they only allow assistant
-        // messages to not have reasoning parts if they only have tool parts.
+        // For DeepSeek and Kimi, append tool part to existing message, for some reason they don't
+        // output reasoning parts following an assistant injection containing either just text part,
+        // or text part with synth reasoning, and there's no docs on how their reasoning encryption
+        // works as far as I can find. IDK what's going on here, seems like the only possible ways
+        // to inject for them is a user role message, or a tool part apeended to last assistant message.
         const providerID = userInfo.model?.providerID || ""
         const modelID = userInfo.model?.modelID || ""
         if (isDeepSeekOrKimi(providerID, modelID)) {