# messages

> **Module** in `@langchain/core`

📖 [View in docs](https://reference.langchain.com/javascript/langchain-core/messages)

## Signature

```javascript
messages
```

## Methods

- [`_isMessageFieldWithRole()`](https://reference.langchain.com/javascript/langchain-core/messages/_isMessageFieldWithRole)
- [`_mergeDicts()`](https://reference.langchain.com/javascript/langchain-core/messages/_mergeDicts)
- [`_mergeLists()`](https://reference.langchain.com/javascript/langchain-core/messages/_mergeLists)
- [`_mergeObj()`](https://reference.langchain.com/javascript/langchain-core/messages/_mergeObj)
- [`_mergeStatus()`](https://reference.langchain.com/javascript/langchain-core/messages/_mergeStatus)
- [`coerceMessageLikeToMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/coerceMessageLikeToMessage)
- [`collapseToolCallChunks()`](https://reference.langchain.com/javascript/langchain-core/messages/collapseToolCallChunks)
- [`convertToChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/convertToChunk)
- [`convertToOpenAIImageBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/convertToOpenAIImageBlock)
- [`convertToProviderContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/convertToProviderContentBlock)
- [`defaultTextSplitter()`](https://reference.langchain.com/javascript/langchain-core/messages/defaultTextSplitter)
- [`filterMessages()`](https://reference.langchain.com/javascript/langchain-core/messages/filterMessages)
- [`getBufferString()`](https://reference.langchain.com/javascript/langchain-core/messages/getBufferString)
- [`iife()`](https://reference.langchain.com/javascript/langchain-core/messages/iife)
- [`isAIMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isAIMessage)
- [`isAIMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isAIMessageChunk)
- [`isBase64ContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/isBase64ContentBlock)
- [`isBaseMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isBaseMessage)
- [`isBaseMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isBaseMessageChunk)
- [`isChatMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isChatMessage)
- [`isChatMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isChatMessageChunk)
- [`isDataContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/isDataContentBlock)
- [`isFunctionMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isFunctionMessage)
- [`isFunctionMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isFunctionMessageChunk)
- [`isHumanMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isHumanMessage)
- [`isHumanMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isHumanMessageChunk)
- [`isIDContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/isIDContentBlock)
- [`isMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isMessage)
- [`isOpenAIToolCallArray()`](https://reference.langchain.com/javascript/langchain-core/messages/isOpenAIToolCallArray)
- [`isPlainTextContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/isPlainTextContentBlock)
- [`isSystemMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isSystemMessage)
- [`isSystemMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isSystemMessageChunk)
- [`isURLContentBlock()`](https://reference.langchain.com/javascript/langchain-core/messages/isURLContentBlock)
- [`mapChatMessagesToStoredMessages()`](https://reference.langchain.com/javascript/langchain-core/messages/mapChatMessagesToStoredMessages)
- [`mapStoredMessagesToChatMessages()`](https://reference.langchain.com/javascript/langchain-core/messages/mapStoredMessagesToChatMessages)
- [`mapStoredMessageToChatMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/mapStoredMessageToChatMessage)
- [`mergeContent()`](https://reference.langchain.com/javascript/langchain-core/messages/mergeContent)
- [`mergeMessageRuns()`](https://reference.langchain.com/javascript/langchain-core/messages/mergeMessageRuns)
- [`mergeResponseMetadata()`](https://reference.langchain.com/javascript/langchain-core/messages/mergeResponseMetadata)
- [`mergeUsageMetadata()`](https://reference.langchain.com/javascript/langchain-core/messages/mergeUsageMetadata)
- [`parseBase64DataUrl()`](https://reference.langchain.com/javascript/langchain-core/messages/parseBase64DataUrl)
- [`parseMimeType()`](https://reference.langchain.com/javascript/langchain-core/messages/parseMimeType)
- [`trimMessages()`](https://reference.langchain.com/javascript/langchain-core/messages/trimMessages)
- [`defaultToolCallParser()`](https://reference.langchain.com/javascript/langchain-core/messages/defaultToolCallParser)
- [`isDirectToolOutput()`](https://reference.langchain.com/javascript/langchain-core/messages/isDirectToolOutput)
- [`isToolMessage()`](https://reference.langchain.com/javascript/langchain-core/messages/isToolMessage)
- [`isToolMessageChunk()`](https://reference.langchain.com/javascript/langchain-core/messages/isToolMessageChunk)

---

[View source on GitHub](https://github.com/langchain-ai/langchainjs/blob/62fc484b2a0d1ec5b8bebff4a8a0efe6300ada72/libs/langchain-core/src/messages/index.ts#L1)