Found docs updates needed from ADK python release v1.14.0 to v1.14.1

[xuanyang15]

Based on the changes from ADK python release v1.14.0 to v1.14.1, we need to update the ADK documentation.

Compare link: google/adk-python@v1.14.0...v1.14.1

Here are the details of the required updates:

1. New Spanner similarity_search tool

A new similarity_search tool has been added to the Spanner toolset. This tool allows for similarity search in Spanner using a text query.

Proposed Change:

Add a new "Spanner" section to docs/tools/built-in-tools.md with the following content:

### Spanner

The `SpannerToolset` provides tools for interacting with Google Cloud Spanner.

* **`similarity_search`**: Performs a similarity search in a Spanner table using a text query. This tool automatically embeds the query text and uses the embedding vector to find similar items in the specified table.

--8<-- "examples/python/snippets/tools/built-in-tools/spanner_similarity_search.py"

Also create a new file examples/python/snippets/tools/built-in-tools/spanner_similarity_search.py with the following content:

from google.adk.agents import Agent
from google.adk.tools.spanner import SpannerToolset

# Initialize the SpannerToolset
spanner_toolset = SpannerToolset(
    project_id="your-gcp-project-id",
    instance_id="your-spanner-instance-id",
    database_id="your-spanner-database-id",
)

# Create an agent with the Spanner tools
root_agent = Agent(
    model="gemini-2.5-flash",
    name="spanner_agent",
    instruction="You are an agent that can perform similarity searches in a Spanner database.",
    tools=spanner_toolset.get_tools(),
)

Reasoning:

This is a new feature that needs to be documented to be discoverable by users.

Reference:

• src/google/adk/tools/spanner/search_tool.py
• src/google/adk/tools/spanner/spanner_toolset.py

2. BigQuery location parameter

The BigQuery tools now support a location parameter to specify the location of the BigQuery client.

Proposed Change:

Update the docs/tools/built-in-tools.md file to include the location parameter in the BigQueryToolset configuration.

Current state:

The documentation for BigQueryToolset does not mention the location parameter.

Proposed Change:

Add a description of the location parameter to the BigQueryToolset initialization example in docs/tools/built-in-tools.md:

from google.adk.tools.bigquery import BigQueryToolset

# Initialize the BigQueryToolset with an optional location
bigquery_toolset = BigQueryToolset(
    project_id="your-gcp-project-id",
    location="us-central1"  # Optional: specify BigQuery location
)

Reasoning:

This is a new parameter that provides more control over the BigQuery client and should be documented.

Reference:

• src/google/adk/tools/bigquery/client.py
• src/google/adk/tools/bigquery/config.py

3. ADK Live agent changes

There are several updates related to ADK Live agents.

a) save_live_audio in RunConfig

Proposed Change:

Add the save_live_audio flag to the RunConfig table in docs/runtime/runconfig.md.

Parameter	Python Type	Java Type	Default (Py / Java)	Description
save_live_audio	bool	boolean	False / false	If true, saves live audio data to session and artifact service.

Reasoning:

This is a new feature for live agents that needs to be documented.

Reference:

• src/google/adk/agents/run_config.py

b) New live_agent_api_server_example

Proposed Change:

Add a link to the new live_agent_api_server_example in docs/get-started/streaming/index.md.

-   :material-console-line: **Live Agent API Server Example**

    This example demonstrates how to set up a live agent with an API server to handle audio streaming.

    [:octicons-arrow-right-24: View Live Agent API Server Example](https://github.com/google/adk-python/tree/main/contributing/samples/live_agent_api_server_example)

Reasoning:

This new example is a valuable resource for users who want to build live agents.

Reference:

• contributing/samples/live_agent_api_server_example/

4. Evaluation rubrics

The EvalCase and Invocation data models in the evaluation framework now include a rubrics field.

Proposed Change:

Update docs/evaluate/index.md to include the rubrics field in the EvalCase and Invocation data models.

Current state:

The documentation does not mention the rubrics field.

Proposed Change:

Add a description of the rubrics field to the EvalCase and Invocation sections in docs/evaluate/index.md.

Reasoning:

This is a new feature in the evaluation framework that needs to be documented.

Reference:

• src/google/adk/evaluation/eval_case.py

5. Model name updates

The recommended model name has been updated from gemini-2.0-flash to gemini-2.5-flash.

Proposed Change:

Perform a global find and replace in the documentation to replace gemini-2.0-flash and gemini-2.0-flash-exp with gemini-2.5-flash.

Reasoning:

To ensure the documentation uses the latest and correct model names.

Reference:

• README.md
• contributing/samples/bigtable/agent.py
• src/google/adk/models/google_llm.py
• src/google/adk/models/lite_llm.py

6. API Reference updates

Several docstrings in the codebase have been updated.

Proposed Change:

Regenerate the API reference documentation to reflect the latest changes in the code.

Reasoning:

To keep the API reference in sync with the codebase.

Reference:

• src/google/adk/events/event.py
• src/google/adk/sessions/session.py
• src/google/adk/models/llm_response.py
• src/google/adk/models/base_llm.py