Tools

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:

tools:
 search_flights_by_number:
    kind: 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`.

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`.
items	parameter object	true	Specify a Parameter object for the type of the values in the array.

Note

Items in array should not have a default or required value. If provided, it will be ignored.

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.

  tools:
    search_flights_by_user_id:
        kind: 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.

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.

tools:
 select_columns_from_table:
    kind: 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

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.
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.

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

Tools

Specifying Parameters

Basic Parameters

Array Parameters

Map Parameters

Generic Map (Mixed Value Types)

Typed Map

Authenticated Parameters

Template Parameters

Authorized Invocations

Kinds of tools

AlloyDB AI NL

BigQuery

Bigtable

ClickHouse

Couchbase

Dataplex

Dgraph

Firebird

Firestore

HTTP

Looker

MongoDB

MySQL

Neo4j

OceanBase

Postgres

Redis

Spanner

SQL Server

SQLite

TiDB

Trino

Utility tools

Valkey