Files
genai-toolbox/docs/en/resources/tools/_index.md
Yuan Teoh 293c1d6889 feat!: update configuration file v2 (#2369)
This PR introduces a significant update to the Toolbox configuration
file format, which is one of the primary **breaking changes** required
for the implementation of the Advanced Control Plane.

# Summary of Changes
The configuration schema has been updated to enforce resource isolation
and facilitate atomic, incremental updates.
* Resource Isolation: Resource definitions are now separated into
individual blocks, using a distinct structure for each resource type
(Source, Tool, Toolset, etc.). This improves readability, management,
and auditing of configuration files.
* Field Name Modification: Internal field names have been modified to
align with declarative methodologies. Specifically, the configuration
now separates kind (general resource type, e.g., Source) from type
(specific implementation, e.g., Postgres).

# User Impact
Existing tools.yaml configuration files are now in an outdated format.
Users must eventually update their files to the new YAML format.

# Mitigation & Compatibility
Backward compatibility is maintained during this transition to ensure no
immediate user action is required for existing files.
* Immediate Backward Compatibility: The source code includes a
pre-processing layer that automatically detects outdated configuration
files (v1 format) and converts them to the new v2 format under the hood.
* [COMING SOON] Migration Support: The new toolbox migrate subcommand
will be introduced to allow users to automatically convert their old
configuration files to the latest format.

# Example
Example for config file v2:
```
kind: sources
name: my-pg-instance
type: cloud-sql-postgres
project: my-project
region: my-region
instance: my-instance
database: my_db
user: my_user
password: my_pass
---
kind: authServices
name: my-google-auth
type: google
clientId: testing-id
---
kind: tools
name: example_tool
type: postgres-sql
source: my-pg-instance
description: some description
statement: SELECT * FROM SQL_STATEMENT;
parameters:
- name: country
  type: string
  description: some description
---
kind: tools
name: example_tool_2
type: postgres-sql
source: my-pg-instance
description: returning the number one
statement: SELECT 1;
---
kind: toolsets
name: example_toolset
tools:
- example_tool
```

---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Averi Kitsch <akitsch@google.com>
2026-01-27 16:58:43 -08:00

14 KiB

title, type, weight, description
title type weight description
Tools docs 2 Tools define actions an agent can take -- such as reading and writing to a source.

A tool represents an action your agent can take, such as running a SQL statement. You can define Tools as a map in the tools section of your tools.yaml file. Typically, a tool will require a source to act on:

kind: tools
name: search_flights_by_number
type: postgres-sql
source: my-pg-instance
statement: |
  SELECT * FROM flights
  WHERE airline = $1
  AND flight_number = $2
  LIMIT 10
description: |
  Use this tool to get information for a specific flight.
  Takes an airline code and flight number and returns info on the flight.
  Do NOT use this tool with a flight id. Do NOT guess an airline code or flight number.
  An airline code is a code for an airline service consisting of a two-character
  airline designator and followed by a flight number, which is a 1 to 4 digit number.
  For example, if given CY 0123, the airline is "CY", and flight_number is "123".
  Another example for this is DL 1234, the airline is "DL", and flight_number is "1234".
  If the tool returns more than one option choose the date closest to today.
  Example:
  {{
      "airline": "CY",
      "flight_number": "888",
  }}
  Example:
  {{
      "airline": "DL",
      "flight_number": "1234",
  }}
parameters:
  - name: airline
    type: string
    description: Airline unique 2 letter identifier
  - name: flight_number
    type: string
    description: 1 to 4 digit number

Specifying Parameters

Parameters for each Tool will define what inputs the agent will need to provide to invoke them. Parameters should be pass as a list of Parameter objects:

parameters:
  - name: airline
    type: string
    description: Airline unique 2 letter identifier
  - name: flight_number
    type: string
    description: 1 to 4 digit number

Basic Parameters

Basic parameters types include string, integer, float, boolean types. In most cases, the description will be provided to the LLM as context on specifying the parameter.

parameters:
  - name: airline
    type: string
    description: Airline unique 2 letter identifier
field type required description
name string true Name of the parameter.
type string true Must be one of "string", "integer", "float", "boolean" "array"
description string true Natural language description of the parameter to describe it to the agent.
default parameter type false Default value of the parameter. If provided, required will be false.
required bool false Indicate if the parameter is required. Default to true.
allowedValues []string false Input value will be checked against this field. Regex is also supported.
excludedValues []string false Input value will be checked against this field. Regex is also supported.
escape string false Only available for type string. Indicate the escaping delimiters used for the parameter. This field is intended to be used with templateParameters. Must be one of "single-quotes", "double-quotes", "backticks", "square-brackets".
minValue int or float false Only available for type integer and float. Indicate the minimum value allowed.
maxValue int or float false Only available for type integer and float. Indicate the maximum value allowed.

Array Parameters

The array type is a list of items passed in as a single parameter. To use the array type, you must also specify what kind of items are in the list using the items field:

parameters:
  - name: preferred_airlines
    type: array
    description: A list of airline, ordered by preference.
    items:
      name: name
      type: string
      description: Name of the airline.
statement: |
  SELECT * FROM airlines WHERE preferred_airlines = ANY($1);
field type required description
name string true Name of the parameter.
type string true Must be "array"
description string true Natural language description of the parameter to describe it to the agent.
default parameter type false Default value of the parameter. If provided, required will be false.
required bool false Indicate if the parameter is required. Default to true.
allowedValues []string false Input value will be checked against this field. Regex is also supported.
excludedValues []string false Input value will be checked against this field. Regex is also supported.
items parameter object true Specify a Parameter object for the type of the values in the array.

{{< notice note >}} Items in array should not have a default or required value. If provided, it will be ignored. {{< /notice >}}

Map Parameters

The map type is a collection of key-value pairs. It can be configured in two ways:

  • Generic Map: By default, it accepts values of any primitive type (string, integer, float, boolean), allowing for mixed data.
  • Typed Map: By setting the valueType field, you can enforce that all values within the map must be of the same specified type.

Generic Map (Mixed Value Types)

This is the default behavior when valueType is omitted. It's useful for passing a flexible group of settings.

parameters:
  - name: execution_context
    type: map
    description: A flexible set of key-value pairs for the execution environment.

Typed Map

Specify valueType to ensure all values in the map are of the same type. An error will be thrown in case of value type mismatch.

parameters:
  - name: user_scores
    type: map
    description: A map of user IDs to their scores. All scores must be integers.
    valueType: integer # This enforces the value type for all entries.

Authenticated Parameters

Authenticated parameters are automatically populated with user information decoded from ID tokens that are passed in request headers. They do not take input values in request bodies like other parameters. To use authenticated parameters, you must configure the tool to map the required authServices to specific claims within the user's ID token.

kind: tools
name: search_flights_by_user_id
type: postgres-sql
source: my-pg-instance
statement: |
  SELECT * FROM flights WHERE user_id = $1
parameters:
  - name: user_id
    type: string
    description: Auto-populated from Google login
    authServices:
      # Refer to one of the `authServices` defined
      - name: my-google-auth
        # `sub` is the OIDC claim field for user ID
        field: sub
field type required description
name string true Name of the authServices used to verify the OIDC auth token.
field string true Claim field decoded from the OIDC token used to auto-populate this parameter.

Template Parameters

Template parameters types include string, integer, float, boolean types. In most cases, the description will be provided to the LLM as context on specifying the parameter. Template parameters will be inserted into the SQL statement before executing the prepared statement. They will be inserted without quotes, so to insert a string using template parameters, quotes must be explicitly added within the string.

Template parameter arrays can also be used similarly to basic parameters, and array items must be strings. Once inserted into the SQL statement, the outer layer of quotes will be removed. Therefore to insert strings into the SQL statement, a set of quotes must be explicitly added within the string.

{{< notice warning >}} Because template parameters can directly replace identifiers, column names, and table names, they are prone to SQL injections. Basic parameters are preferred for performance and safety reasons. {{< /notice >}}

{{< notice tip >}} To minimize SQL injection risk when using template parameters, always provide the allowedValues field within the parameter to restrict inputs. Alternatively, for string type parameters, you can use the escape field to add delimiters to the identifier. For integer or float type parameters, you can use minValue and maxValue to define the allowable range. {{< /notice >}}

kind: tools
name: select_columns_from_table
type: postgres-sql
source: my-pg-instance
statement: |
  SELECT {{array .columnNames}} FROM {{.tableName}}
description: |
  Use this tool to list all information from a specific table.
  Example:
  {{
      "tableName": "flights",
      "columnNames": ["id", "name"]
  }}
templateParameters:
  - name: tableName
    type: string
    description: Table to select from
  - name: columnNames
    type: array
    description: The columns to select
    items:
      name: column
      type: string
      description: Name of a column to select
      escape: double-quotes # with this, the statement will resolve to `SELECT "id", "name" FROM flights`
field type required description
name string true Name of the template parameter.
type string true Must be one of "string", "integer", "float", "boolean", "array"
description string true Natural language description of the template parameter to describe it to the agent.
default parameter type false Default value of the parameter. If provided, required will be false.
required bool false Indicate if the parameter is required. Default to true.
allowedValues []string false Input value will be checked against this field. Regex is also supported.
excludedValues []string false Input value will be checked against this field. Regex is also supported.
items parameter object true (if array) Specify a Parameter object for the type of the values in the array (string only).

Authorized Invocations

You can require an authorization check for any Tool invocation request by specifying an authRequired field. Specify a list of authServices defined in the previous section.

kind: tools
name: search_all_flight
type: postgres-sql
source: my-pg-instance
statement: |
  SELECT * FROM flights
# A list of `authServices` defined previously
authRequired:
  - my-google-auth
  - other-auth-service

Kinds of tools