Add SDK FAQ documentation with parallel tool calling information (#149)

* Add FAQ documentation for SDK with parallel tool calling info

- Created new sdk/faq.mdx with detailed information about parallel tool calling support
- Added FAQ page to docs.json navigation right below 'Getting Started'
- Included code references and links to architecture documentation
- Explained how parallel tool calling works with llm_response_id grouping

* Compact related documentation links into one paragraph

* Compact 'How it works' section into collapsible Accordion

- Converted detailed 'How it works' section into a Mintlify Accordion component
- Made the content more concise while preserving key information
- Improves readability by allowing users to expand details on demand

* Compact code references section into one paragraph

* Convert code references and related documentation into collapsible accordions

* Merge all three accordions into one 'How it works' section

---------

Co-authored-by: openhands <openhands@all-hands.dev>

Author: xingyaoww

docs.json

@@ -192,6 +192,7 @@
         "pages": [
           "sdk/index",
           "sdk/getting-started",
+          "sdk/faq",
           {
             "group": "Guides",
             "pages": [

sdk/faq.mdx

@@ -0,0 +1,31 @@
+---
+title: FAQ
+description: Frequently asked questions about the OpenHands SDK
+icon: question
+---
+
+## Does the agent SDK support parallel tool calling?
+
+**Yes, the OpenHands SDK supports parallel tool calling by default.**
+
+The SDK automatically handles parallel tool calls when the underlying LLM (like Claude or GPT-4) returns multiple tool calls in a single response. This allows agents to execute multiple independent actions simultaneously, improving efficiency.
+
+<Accordion title="How it works" icon="gear">
+When the LLM generates multiple tool calls in parallel, the SDK groups them using a shared `llm_response_id`:
+
+```python
+ActionEvent(llm_response_id="abc123", thought="Let me check...", tool_call=tool1)
+ActionEvent(llm_response_id="abc123", thought=[], tool_call=tool2)
+# Combined into: Message(role="assistant", content="Let me check...", tool_calls=[tool1, tool2])
+```
+
+Multiple `ActionEvent`s with the same `llm_response_id` are grouped together and combined into a single LLM message with multiple `tool_calls`. Only the first event's thought/reasoning is included. The parallel tool calling implementation can be found in the [Events Architecture](/sdk/arch/events#event-types) for detailed explanation of how parallel function calling works, the [`prepare_llm_messages` in utils.py](https://github.com/OpenHands/software-agent-sdk/blob/main/openhands-sdk/openhands/sdk/agent/utils.py) which groups ActionEvents by `llm_response_id` when converting events to LLM messages, the [agent step method](https://github.com/OpenHands/software-agent-sdk/blob/main/openhands-sdk/openhands/sdk/agent/agent.py#L200-L300) where actions are created with shared `llm_response_id`, and the [`ActionEvent` class](https://github.com/OpenHands/software-agent-sdk/blob/main/openhands-sdk/openhands/sdk/event/llm_convertible/action.py) which includes the `llm_response_id` field. For more details, see the **[Events Architecture](/sdk/arch/events)** for a deep dive into the event system and parallel function calling, the **[Tool System](/sdk/arch/tool-system)** for understanding how tools work with the agent, and the **[Agent Architecture](/sdk/arch/agent)** for how agents process and execute actions.
+</Accordion>
+
+## More questions?
+
+If you have additional questions:
+
+- **[Join our Slack Community](https://openhands.dev/joinslack)** - Ask questions and get help from the community
+- **[GitHub Discussions](https://github.com/OpenHands/software-agent-sdk/discussions)** - Start a discussion
+- **[GitHub Issues](https://github.com/OpenHands/software-agent-sdk/issues)** - Report bugs or request features