> ## Documentation Index
> Fetch the complete documentation index at: https://allhandsai-client-message-context.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Client Message Context

> Attach client-generated context to a user message without changing its visible content.

Use `client_context` when an SDK client needs to provide current environment details with a user turn. The context is persisted in the user `MessageEvent.extended_content` and included when that event is converted to LLM input. The original message content remains separate.

```python theme={null}
from openhands.sdk import TextContent

conversation.send_message(
    "Inspect the running services.",
    client_context=[
        TextContent(
            text="<RUNTIME_SERVICES>API: http://runtime:8000</RUNTIME_SERVICES>"
        )
    ],
)
```

This is useful for context owned by the client rather than the agent configuration, such as:

* Runtime URLs that may change after a conversation moves.
* UI capabilities available for the current session.
* Workspace or deployment metadata relevant to the next turn.

Attach the context to the first applicable user message. If the environment changes later, attach the updated context to the next user message.

<Warning>
  `client_context` is not a security boundary. It is stored with the conversation and should not contain secrets.
</Warning>

## Remote Agent Server

The same field is available on the initial message in `POST /api/conversations` and on later messages in `POST /api/conversations/{conversation_id}/events`:

```json theme={null}
{
  "role": "user",
  "content": [{ "type": "text", "text": "Inspect the running services." }],
  "client_context": [
    {
      "type": "text",
      "text": "<RUNTIME_SERVICES>API: http://runtime:8000</RUNTIME_SERVICES>"
    }
  ],
  "run": true
}
```

The server maps `client_context` to `MessageEvent.extended_content`. Consumers that render the visible message should continue to use `MessageEvent.llm_message.content`; LLM conversion includes both fields.