LlmAgentConfig.model now accepts either a plain model string or a CodeConfig. This lets YAML configs pass a LiteLLM instance with managed API settings (e.g., api_base and fallbacks) so agents can hit KimiK2’s managed endpoint instead of only the default modelID.
Close#3579
Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 838978654
Merge https://github.com/google/adk-python/pull/3576
**Please ensure you have read the [contribution guide](https://github.com/google/adk-python/blob/main/CONTRIBUTING.md) before creating a pull request.**
### Link to Issue or Description of Change
**1. Link to an existing issue (if applicable):**
- Closes: #3557
- Related: #_issue_number_
**2. Or, if no issue exists, describe the change:**
_If applicable, please follow the issue templates to provide as much detail as
possible._
**Problem:**
When creating a BaseAgent with multiple sub-agents, there was no validation to ensure that all sub-agents have unique names. This could lead to confusion when trying to find or reference specific sub-agents by name, as duplicate names would make it ambiguous which agent is being referenced.
**Solution:**
Added a @field_validator for the sub_agents field in BaseAgent that validates all sub-agents have unique names. The validator:
Checks for duplicate names in the sub-agents list
Raises a ValueError with a clear error message listing all duplicate names found
Returns the validated list if all names are unique
Handles edge cases like empty lists gracefully
### Testing Plan
_Please describe the tests that you ran to verify your changes. This is required
for all PRs that are not small documentation or typo fixes._
**Unit Tests:**
- [x] I have added or updated unit tests for my change.
- [x] All unit tests pass locally.
_Please include a summary of passed `pytest` results._
Added 4 new test cases in tests/unittests/agents/test_base_agent.py:
test_validate_sub_agents_unique_names_single_duplicate: Verifies that a single duplicate name raises ValueError
test_validate_sub_agents_unique_names_multiple_duplicates: Verifies that multiple duplicate names are all reported in the error message
test_validate_sub_agents_unique_names_no_duplicates: Verifies that unique names pass validation successfully
test_validate_sub_agents_unique_names_empty_list: Verifies that empty sub-agents list passes validation
All tests pass locally. You can run with:
pytest tests/unittests/agents/test_base_agent.py::test_validate_sub_agents_unique_names_single_duplicate tests/unittests/agents/test_base_agent.py::test_validate_sub_agents_unique_names_multiple_duplicates tests/unittests/agents/test_base_agent.py::test_validate_sub_agents_unique_names_no_duplicates tests/unittests/agents/test_base_agent.py::test_validate_sub_agents_unique_names_empty_list -v
**Manual End-to-End (E2E) Tests:**
_Please provide instructions on how to manually test your changes, including any
necessary setup or configuration. Please provide logs or screenshots to help
reviewers better understand the fix._
Test Case 1: Duplicate names should raise error
from google.adk.agents import Agent
agent1 = Agent(name="sub_agent", model="gemini-2.5-flash")
agent2 = Agent(name="sub_agent", model="gemini-2.5-flash") # Same name
# This should raise ValueError
try:
parent = Agent(
name="parent",
model="gemini-2.5-flash",
sub_agents=[agent1, agent2]
)
except ValueError as e:
print(f"Expected error: {e}")
# Output: Found duplicate sub-agent names: `sub_agent`. All sub-agents must have unique names.
Test Case 2: Unique names should work
from google.adk.agents import Agent
agent1 = Agent(name="agent1", model="gemini-2.5-flash")
agent2 = Agent(name="agent2", model="gemini-2.5-flash")
# This should work without error
parent = Agent(
name="parent",
model="gemini-2.5-flash",
sub_agents=[agent1, agent2]
)
print("Success: Unique names validated correctly")
### Checklist
- [x] I have read the [CONTRIBUTING.md](https://github.com/google/adk-python/blob/main/CONTRIBUTING.md) document.
- [x] I have performed a self-review of my own code.
- [x] I have commented my code, particularly in hard-to-understand areas.
- [x] I have added tests that prove my fix is effective or that my feature works.
- [x] New and existing unit tests pass locally with my changes.
- [x] I have manually tested my changes end-to-end.
- [x] Any dependent changes have been merged and published in downstream modules.
### Additional context
This change adds validation at the BaseAgent level, so it automatically applies to all agent types that inherit from BaseAgent (e.g., LlmAgent, LoopAgent, etc.). The validation uses Pydantic's field validator system, which runs during object initialization, ensuring the constraint is enforced early and consistently.
The error message clearly identifies which names are duplicated, making it easy for developers to fix the issue:
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/3576 from sarojrout:feat/validate-unique-sub-agent-names 07adf1f9a5fc935389eb9dfa3cbc1311f551ebe3
PiperOrigin-RevId: 835358118
The change adds an extension point for controlling which request metadata gets attached to A2A requests made by a RemoteAgent.
Instead of taking metadata from custom_metadata of session events users can construct payloads using a2a_request_meta_provider.
request_meta feature was added in v0.3.11 of the a2a-sdk library: https://github.com/a2aproject/a2a-python/releases/tag/v0.3.11
PiperOrigin-RevId: 831506364
This change updates `RemoteA2AAgent` to extract and forward custom metadata from session events to the `a2a-sdk`'s `send_message` method. The metadata is looked for under the key `A2A_METADATA_PREFIX + "metadata"` within the `custom_metadata` of the relevant session events. The `a2a-sdk` dependency is also updated to a version that supports this feature.
This feature was added in v0.3.11 of the a2a-sdk library: https://github.com/a2aproject/a2a-python/releases/tag/v0.3.11
PiperOrigin-RevId: 831120978
Enhanced `save_artifact` in `callback_context.py` to accept `custom_metadata` and added `get_artifact_version` to retrieve artifact details.
Introduced a new sample, `context_offloading_with_artifact`, demonstrating how to use ADK artifacts to offload large data from the LLM context. The sample includes:
- `QueryLargeDataTool`: Generates mock sales reports, saves them as artifacts with custom metadata, and injects the artifact content into the LLM request immediately after creation.
- `CustomLoadArtifactsTool`: Provides summaries of available artifacts to the LLM based on metadata and loads artifact content on demand when `load_artifacts` is called.
Co-authored-by: Hangfei Lin <hangfei@google.com>
PiperOrigin-RevId: 830592786
Merge https://github.com/google/adk-python/pull/2875
related: https://github.com/google/adk-python/issues/2876
## Reason for this change:
Currently, there is no direct way to access the user_id from within agent contexts, plugins, or callbacks. This limitation prevents several important use cases:
1. **User-specific logging and tracing**: When debugging or monitoring agent behavior, it's crucial to associate actions with specific users for better observability.
2. **User-scoped operations**: Plugins and callbacks often need to perform user-specific operations, such as accessing user-specific resources or applying user-level configurations.
3. **Session management**: The user_id is a key component of session identification, but it's not accessible through the ReadonlyContext interface, requiring workarounds to access it.
## Changes made:
- Added a `user_id` property to the `ReadonlyContext` class in `src/google/adk/agents/readonly_context.py`
- The property exposes the user_id from the underlying invocation context as a readonly field
## Impact:
This change will:
- Enable plugins and callbacks to access the current user's ID directly through the context
- Improve logging and tracing capabilities by allowing user-specific tracking
- Simplify code that needs to perform user-scoped operations without requiring access to internal implementation details
- Maintain backward compatibility as this is an additive change
### Before:
- No direct way to access user_id from ReadonlyContext
### After:
```python
@property
def user_id(self) -> str:
"""The id of the user. READONLY field."""
return self._invocation_context.user_id
```
This is a non-breaking change that adds a new readonly property to the existing ReadonlyContext interface.
Co-authored-by: Hangfei Lin <hangfei@google.com>
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/2875 from ammmr:ammmr-add-user_id-property-to-readonly-context 771734ebf39cb0748a5dc826436236268fbb58f8
PiperOrigin-RevId: 830170908
Add support for MCP prompts via the McpInstructionProvider class, which can be specified as an agent's instruction.
Co-authored-by: Kathy Wu <wukathy@google.com>
PiperOrigin-RevId: 828166051
Merge https://github.com/google/adk-python/pull/3219
## Summary
Enhance error messages for tool and agent not found errors to provide actionable guidance and reduce developer debugging time from hours to minutes.
Fixes#3217
## Changes
### Modified Files
1. **`src/google/adk/flows/llm_flows/functions.py`**
- Enhanced `_get_tool()` error message with:
- Available tools list (formatted, truncated to 20 for readability)
- Possible causes
- Suggested fixes
- Fuzzy matching suggestions
2. **`src/google/adk/agents/llm_agent.py`**
- Enhanced `__get_agent_to_run()` error message with:
- Available agents list (formatted, truncated to 20 for readability)
- Timing/ordering issue explanation
- Fuzzy matching for agent names
- Added `_get_available_agent_names()` helper method
### New Test Files
3. **`tests/unittests/flows/llm_flows/test_functions_error_messages.py`**
- Tests for enhanced tool not found error messages
- Fuzzy matching validation
- Edge cases (no close matches, empty tools dict, 100+ tools)
4. **`tests/unittests/agents/test_llm_agent_error_messages.py`**
- Tests for enhanced agent not found error messages
- Agent tree traversal validation
- Fuzzy matching for agents
- Long list truncation
## Testing Plan
### Unit Tests
```bash
pytest tests/unittests/flows/llm_flows/test_functions_error_messages.py -v
pytest tests/unittests/agents/test_llm_agent_error_messages.py -v
```
**Results**: ✅ 8/8 tests passing
```
tests/unittests/flows/llm_flows/test_functions_error_messages.py::test_tool_not_found_enhanced_error PASSED
tests/unittests/flows/llm_flows/test_functions_error_messages.py::test_tool_not_found_fuzzy_matching PASSED
tests/unittests/flows/llm_flows/test_functions_error_messages.py::test_tool_not_found_no_fuzzy_match PASSED
tests/unittests/flows/llm_flows/test_functions_error_messages.py::test_tool_not_found_truncates_long_list PASSED
tests/unittests/agents/test_llm_agent_error_messages.py::test_agent_not_found_enhanced_error PASSED
tests/unittests/agents/test_llm_agent_error_messages.py::test_agent_not_found_fuzzy_matching PASSED
tests/unittests/agents/test_llm_agent_error_messages.py::test_agent_tree_traversal PASSED
tests/unittests/agents/test_llm_agent_error_messages.py::test_agent_not_found_truncates_long_list PASSED
8 passed, 1 warning in 4.38s
```
### Example Enhanced Error Messages
#### Before (Current Error)
```
ValueError: Function get_equipment_specs is not found in the tools_dict: dict_keys(['get_equipment_details', 'query_vendor_catalog', 'score_proposals'])
```
#### After (Enhanced Error)
```
Function 'get_equipment_specs' is not found in available tools.
Available tools: get_equipment_details, query_vendor_catalog, score_proposals
Possible causes:
1. LLM hallucinated the function name - review agent instruction clarity
2. Tool not registered - verify agent.tools list
3. Name mismatch - check for typos
Suggested fixes:
- Review agent instruction to ensure tool usage is clear
- Verify tool is included in agent.tools list
- Check for typos in function name
Did you mean one of these?
- get_equipment_details
```
## Community Impact
- **Addresses 3 active issues**: #2050, #2933 (12 comments), #2164
- **Reduces debugging time** from 3+ hours to < 5 minutes (validated in production multi-agent RFQ solution for recent partner nanothon initiative)
- **Improves developer experience** for new ADK users
## Implementation Details
- Uses standard library `difflib` for fuzzy matching (no new dependencies)
- Error path only (no performance impact on happy path)
- Measured performance: < 0.03ms per error
- Truncates long lists to first 20 items to prevent log overflow
- Fully backward compatible (same exception types)
## Checklist
- [x] Unit tests added and passing (8/8 tests)
- [x] Code formatted with `./autoformat.sh` (isort + pyink)
- [x] No new dependencies (uses standard library `difflib`)
- [x] Docstrings updated
- [x] Tested with Python 3.11
- [x] Issue #3217 created and linked
## Related Issues
- Fixes#3217
- Addresses #2050 - Tool verification callback request
- Addresses #2933 - How to handle "Function is not found in the tools_dict" Error
- Addresses #2164 - ValueError: {agent} not found in agent tree
---
**Note**: For production scenarios where LLM tool hallucinations occur, ADK's built-in [`ReflectAndRetryToolPlugin`](https://github.com/google/adk-python/blob/main/src/google/adk/plugins/reflect_retry_tool_plugin.py) can automatically retry failed tool calls (available since v1.16.0). This PR's enhanced error messages complement that by helping developers quickly identify and fix configuration issues during development.
Cheers, JP
Co-authored-by: Yvonne Yu <yyyu@google.com>
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/3219 from jpantsjoha:feat/better-error-messages a4df8bfb031685dce9e528d8eb7006f53447b75b
PiperOrigin-RevId: 826132579
Remove validation for output_schema and agent transfer flags.
The check that prevented `output_schema` from co-existing with agent transfer capabilities (`disallow_transfer_to_parent` or `disallow_transfer_to_peers` being False) has been removed. The agent will no longer automatically set these transfer flags to True when `output_schema` is present.
Co-authored-by: Ieva Grublyte <ievagrublyte@google.com>
PiperOrigin-RevId: 825998224
Previously this will return true for events yielded from before_agent_callback when there are state changes.
Note with this change, it will also return false for state delta only callbacks even after main response, but this is fine as long as the actual final response event has it to be true.
Closes#2992
PiperOrigin-RevId: 825313208
Previously this will return true for events yielded from before_agent_callback when there are state changes.
Note with this change, it will also return false for state delta only callbacks even after main response, but this is fine as long as the actual final response event has it to be true.
Closes#2992
PiperOrigin-RevId: 825279439
This is so we don't need to worry about side effect of Loop in all agent type. Custom agent should do the same if there exists loop inside.
PiperOrigin-RevId: 818766305