chore: release v0.1.6 (#301)

This PR updates the version to 0.1.6 after publishing to PyPI.

## Changes
- Updated version in `pyproject.toml`
- Updated version in `src/claude_agent_sdk/_version.py`
- Updated `CHANGELOG.md` with release notes

## Release Information
- Published to PyPI: https://pypi.org/project/claude-agent-sdk/0.1.6/
- Install with: `pip install claude-agent-sdk==0.1.6`

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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
Co-authored-by: Ashwin Bhat <[email protected]>

Author: github-actions[bot]

CHANGELOG.md

@@ -1,5 +1,16 @@
 # Changelog
 
+## 0.1.6
+
+### Features
+
+- **Max budget control**: Added `max_budget_usd` option to set a maximum spending limit in USD for SDK sessions. When the budget is exceeded, the session will automatically terminate, helping prevent unexpected costs (#293)
+- **Extended thinking configuration**: Added `max_thinking_tokens` option to control the maximum number of tokens allocated for Claude's internal reasoning process. This allows fine-tuning of the balance between response quality and token usage (#298)
+
+### Bug Fixes
+
+- **System prompt defaults**: Fixed issue where a default system prompt was being used when none was specified. The SDK now correctly uses an empty system prompt by default, giving users full control over agent behavior (#290)
+
 ## 0.1.5
 
 ### Features

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "claude-agent-sdk"
-version = "0.1.5"
+version = "0.1.6"
 description = "Python SDK for Claude Code"
 readme = "README.md"
 requires-python = ">=3.10"

src/claude_agent_sdk/_version.py

@@ -1,3 +1,3 @@
 """Version information for claude-agent-sdk."""
 
-__version__ = "0.1.5"
+__version__ = "0.1.6"