Tool: list_instances
List Spanner instances in a given project. * Response may include next_page_token to fetch additional instances using list_instances tool with page_token set.
The following sample demonstrate how to use curl
to invoke the list_instances
MCP tool.
| Curl Request |
|---|
curl --location 'https://spanner.googleapis.com/mcp' \ --header 'content-type: application/json' \ --header 'accept: application/json, text/event-stream' \ --data '{ "method": "tools/call", "params": { "name": "list_instances", "arguments": { // provide these details according to the tool' s MCP specification } } , "jsonrpc" : "2.0" , "id" : 1 } ' |
Input Schema
The request for ListInstances
.
ListInstancesRequest
| JSON representation |
|---|
{ "parent" : string , "pageSize" : integer , "pageToken" : string , "filter" : string , "instanceDeadline" : string } |
parent
string
Required. The name of the project for which a list of instances is requested. Values are of the form projects/<project>
.
pageSize
integer
Number of instances to be returned in the response. If 0 or less, defaults to the server's maximum allowed page size.
pageToken
string
If non-empty, page_token
should contain a next_page_token
from a previous ListInstancesResponse
.
filter
string
An expression for filtering the results of the request. Filter rules are case insensitive. The fields eligible for filtering are:
-
name -
display_name -
labels.keywhere key is the name of a label
Some examples of using filters are:
-
name:*--> The instance has a name. -
name:Howl--> The instance's name contains the string "howl". -
name:HOWL--> Equivalent to above. -
NAME:howl--> Equivalent to above. -
labels.env:*--> The instance has the label "env". -
labels.env:dev--> The instance has the label "env" and the value of the label contains the string "dev". -
name:howl labels.env:dev--> The instance's name contains "howl" and it has the label "env" with its value containing "dev".
instanceDeadline
string (
Timestamp
format)
Deadline used while retrieving metadata for instances. Instances whose metadata cannot be retrieved within this deadline will be added to unreachable
in ListInstancesResponse
.
Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: "2014-10-02T15:01:23Z"
, "2014-10-02T15:01:23.045123456Z"
or "2014-10-02T15:01:23+05:30"
.
Timestamp
| JSON representation |
|---|
{ "seconds" : string , "nanos" : integer } |
| Fields | |
|---|---|
seconds
|
Represents seconds of UTC time since Unix epoch 1970-01-01T00:00:00Z. Must be between -62135596800 and 253402300799 inclusive (which corresponds to 0001-01-01T00:00:00Z to 9999-12-31T23:59:59Z). |
nanos
|
Non-negative fractions of a second at nanosecond resolution. This field is the nanosecond portion of the duration, not an alternative to seconds. Negative second values with fractions must still have non-negative nanos values that count forward in time. Must be between 0 and 999,999,999 inclusive. |
Output Schema
The response for ListInstances
.
ListInstancesResponse
| JSON representation |
|---|
{
"instances"
:
[
{
object (
|
| Fields | |
|---|---|
instances[]
|
The list of requested instances. |
nextPageToken
|
|
unreachable[]
|
The list of unreachable instances. It includes the names of instances whose metadata could not be retrieved within |
Instance
| JSON representation |
|---|
{ "name" : string , "config" : string , "displayName" : string , "nodeCount" : integer , "processingUnits" : integer , "replicaComputeCapacity" : [ { object ( |
name
string
Required. A unique identifier for the instance, which cannot be changed after the instance is created. Values are of the form projects/<project>/instances/[a-z][-a-z0-9]*[a-z0-9]
. The final segment of the name must be between 2 and 64 characters in length.
config
string
Required. The name of the instance's configuration. Values are of the form projects/<project>/instanceConfigs/<configuration>
. See also InstanceConfig
and ListInstanceConfigs
.
displayName
string
Required. The descriptive name for this instance as it appears in UIs. Must be unique per project and between 4 and 30 characters in length.
nodeCount
integer
The number of nodes allocated to this instance. At most, one of either node_count
or processing_units
should be present in the message.
Users can set the node_count
field to specify the target number of nodes allocated to the instance.
If autoscaling is enabled, node_count
is treated as an OUTPUT_ONLY
field and reflects the current number of nodes allocated to the instance.
This might be zero in API responses for instances that are not yet in the READY
state.
If the instance has varying node count across replicas (achieved by setting asymmetric_autoscaling_options
in the autoscaling configuration), the node_count
set here is the maximum node count across all replicas.
For more information, see Compute capacity, nodes, and processing units .
processingUnits
integer
The number of processing units allocated to this instance. At most, one of either processing_units
or node_count
should be present in the message.
Users can set the processing_units
field to specify the target number of processing units allocated to the instance.
If autoscaling is enabled, processing_units
is treated as an OUTPUT_ONLY
field and reflects the current number of processing units allocated to the instance.
This might be zero in API responses for instances that are not yet in the READY
state.
If the instance has varying processing units per replica (achieved by setting asymmetric_autoscaling_options
in the autoscaling configuration), the processing_units
set here is the maximum processing units across all replicas.
For more information, see Compute capacity, nodes and processing units .
replicaComputeCapacity[]
object (
ReplicaComputeCapacity
)
Output only. Lists the compute capacity per ReplicaSelection. A replica selection identifies a set of replicas with common properties. Replicas identified by a ReplicaSelection are scaled with the same compute capacity.
autoscalingConfig
object (
AutoscalingConfig
)
Optional. The autoscaling configuration. Autoscaling is enabled if this field is set. When autoscaling is enabled, node_count and processing_units are treated as OUTPUT_ONLY fields and reflect the current compute capacity allocated to the instance.
state
enum (
State
)
Output only. The current instance state. For CreateInstance
, the state must be either omitted or set to CREATING
. For UpdateInstance
, the state must be either omitted or set to READY
.
labels
map (key: string, value: string)
Cloud Labels are a flexible and lightweight mechanism for organizing cloud resources into groups that reflect a customer's organizational needs and deployment strategies. Cloud Labels can be used to filter collections of resources. They can be used to control how resource metrics are aggregated. And they can be used as arguments to policy management rules (e.g. route, firewall, load balancing, etc.).
- Label keys must be between 1 and 63 characters long and must conform to the following regular expression:
[a-z][a-z0-9_-]{0,62}. - Label values must be between 0 and 63 characters long and must conform to the regular expression
[a-z0-9_-]{0,63}. - No more than 64 labels can be associated with a given resource.
See https://goo.gl/xmQnxf for more information on and examples of labels.
If you plan to use labels in your own code, please note that additional characters may be allowed in the future. And so you are advised to use an internal label representation, such as JSON, which doesn't rely upon specific characters being disallowed. For example, representing labels as the string: name + "_" + value would prove problematic if we were to allow "_" in a future release.
An object containing a list of "key": value
pairs. Example: { "name": "wrench", "mass": "1.3kg", "count": "3" }
.
instanceType
enum (
InstanceType
)
The InstanceType
of the current instance.
endpointUris[]
string
Deprecated. This field is not populated.
createTime
string (
Timestamp
format)
Output only. The time at which the instance was created.
Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: "2014-10-02T15:01:23Z"
, "2014-10-02T15:01:23.045123456Z"
or "2014-10-02T15:01:23+05:30"
.
updateTime
string (
Timestamp
format)
Output only. The time at which the instance was most recently updated.
Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: "2014-10-02T15:01:23Z"
, "2014-10-02T15:01:23.045123456Z"
or "2014-10-02T15:01:23+05:30"
.
freeInstanceMetadata
object (
FreeInstanceMetadata
)
Free instance metadata. Only populated for free instances.
edition
enum (
Edition
)
Optional. The Edition
of the current instance.
defaultBackupScheduleType
enum (
DefaultBackupScheduleType
)
Optional. Controls the default backup schedule behavior for new databases within the instance. By default, a backup schedule is created automatically when a new database is created in a new instance.
Note that the AUTOMATIC
value isn't permitted for free instances, as backups and backup schedules aren't supported for free instances.
In the GetInstance
or ListInstances
response, if the value of default_backup_schedule_type
isn't set, or set to NONE
, Spanner doesn't create a default backup schedule for new databases in the instance.
ReplicaComputeCapacity
| JSON representation |
|---|
{ "replicaSelection" : { object ( |
replicaSelection
object (
ReplicaSelection
)
Required. Identifies replicas by specified properties. All replicas in the selection have the same amount of compute capacity.
compute_capacity
. Compute capacity allocated to each replica identified by the specified selection. The unit is selected based on the unit used to specify the instance size for non-autoscaling instances, or the unit used in autoscaling limit for autoscaling instances. compute_capacity
can be only one of the following:nodeCount
integer
The number of nodes allocated to each replica.
This may be zero in API responses for instances that are not yet in state READY
.
processingUnits
integer
The number of processing units allocated to each replica.
This may be zero in API responses for instances that are not yet in state READY
.
ReplicaSelection
| JSON representation |
|---|
{ "location" : string } |
| Fields | |
|---|---|
location
|
Required. Name of the location of the replicas (for example, "us-central1"). |
AutoscalingConfig
| JSON representation |
|---|
{ "autoscalingLimits" : { object ( |
| Fields | |
|---|---|
autoscalingLimits
|
Required. Autoscaling limits for an instance. |
autoscalingTargets
|
Required. The autoscaling targets for an instance. |
asymmetricAutoscalingOptions[]
|
Optional. Optional asymmetric autoscaling options. Replicas matching the replica selection criteria will be autoscaled independently from other replicas. The autoscaler will scale the replicas based on the utilization of replicas identified by the replica selection. Replica selections should not overlap with each other. Other replicas (those do not match any replica selection) will be autoscaled together and will have the same compute capacity allocated to them. |
AutoscalingLimits
| JSON representation |
|---|
{ // Union field |
min_limit
. The minimum compute capacity for the instance. min_limit
can be only one of the following:minNodes
integer
Minimum number of nodes allocated to the instance. If set, this number should be greater than or equal to 1.
minProcessingUnits
integer
Minimum number of processing units allocated to the instance. If set, this number should be multiples of 1000.
max_limit
. The maximum compute capacity for the instance. The maximum compute capacity should be less than or equal to 10X the minimum compute capacity. max_limit
can be only one of the following:maxNodes
integer
Maximum number of nodes allocated to the instance. If set, this number should be greater than or equal to min_nodes.
maxProcessingUnits
integer
Maximum number of processing units allocated to the instance. If set, this number should be multiples of 1000 and be greater than or equal to min_processing_units.
AutoscalingTargets
| JSON representation |
|---|
{ "highPriorityCpuUtilizationPercent" : integer , "totalCpuUtilizationPercent" : integer , "storageUtilizationPercent" : integer } |
| Fields | |
|---|---|
highPriorityCpuUtilizationPercent
|
Optional. The target high priority cpu utilization percentage that the autoscaler should be trying to achieve for the instance. This number is on a scale from 0 (no utilization) to 100 (full utilization). The valid range is [10, 90] inclusive. If not specified or set to 0, the autoscaler skips scaling based on high priority CPU utilization. |
totalCpuUtilizationPercent
|
Optional. The target total CPU utilization percentage that the autoscaler should be trying to achieve for the instance. This number is on a scale from 0 (no utilization) to 100 (full utilization). The valid range is [10, 90] inclusive. If not specified or set to 0, the autoscaler skips scaling based on total CPU utilization. If both |
storageUtilizationPercent
|
Required. The target storage utilization percentage that the autoscaler should be trying to achieve for the instance. This number is on a scale from 0 (no utilization) to 100 (full utilization). The valid range is [10, 99] inclusive. |
AsymmetricAutoscalingOption
| JSON representation |
|---|
{ "replicaSelection" : { object ( |
| Fields | |
|---|---|
replicaSelection
|
Required. Selects the replicas to which this AsymmetricAutoscalingOption applies. Only read-only replicas are supported. |
overrides
|
Optional. Overrides applied to the top-level autoscaling configuration for the selected replicas. |
AutoscalingConfigOverrides
| JSON representation |
|---|
{
"autoscalingLimits"
:
{
object (
|
| Fields | |
|---|---|
autoscalingLimits
|
Optional. If specified, overrides the min/max limit in the top-level autoscaling configuration for the selected replicas. |
autoscalingTargetHighPriorityCpuUtilizationPercent
|
Optional. If specified, overrides the autoscaling target high_priority_cpu_utilization_percent in the top-level autoscaling configuration for the selected replicas. |
autoscalingTargetTotalCpuUtilizationPercent
|
Optional. If specified, overrides the autoscaling target |
disableHighPriorityCpuAutoscaling
|
Optional. If true, disables high priority CPU autoscaling for the selected replicas and ignores When setting this field to true, setting If false, the Setting both |
disableTotalCpuAutoscaling
|
Optional. If true, disables total CPU autoscaling for the selected replicas and ignores When setting this field to true, setting If false, the Setting both |
LabelsEntry
| JSON representation |
|---|
{ "key" : string , "value" : string } |
| Fields | |
|---|---|
key
|
|
value
|
|
Timestamp
| JSON representation |
|---|
{ "seconds" : string , "nanos" : integer } |
| Fields | |
|---|---|
seconds
|
Represents seconds of UTC time since Unix epoch 1970-01-01T00:00:00Z. Must be between -62135596800 and 253402300799 inclusive (which corresponds to 0001-01-01T00:00:00Z to 9999-12-31T23:59:59Z). |
nanos
|
Non-negative fractions of a second at nanosecond resolution. This field is the nanosecond portion of the duration, not an alternative to seconds. Negative second values with fractions must still have non-negative nanos values that count forward in time. Must be between 0 and 999,999,999 inclusive. |
FreeInstanceMetadata
| JSON representation |
|---|
{
"expireTime"
:
string
,
"upgradeTime"
:
string
,
"expireBehavior"
:
enum (
|
| Fields | |
|---|---|
expireTime
|
Output only. Timestamp after which the instance will either be upgraded or scheduled for deletion after a grace period. ExpireBehavior is used to choose between upgrading or scheduling the free instance for deletion. This timestamp is set during the creation of a free instance. Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: |
upgradeTime
|
Output only. If present, the timestamp at which the free instance was upgraded to a provisioned instance. Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: |
expireBehavior
|
Specifies the expiration behavior of a free instance. The default of ExpireBehavior is |
Tool Annotations
Destructive Hint: ❌ | Idempotent Hint: ❌ | Read Only Hint: ✅ | Open World Hint: ❌

