# ToolInvocationContract
> Tracon documentation. Tracon is a .NET package family that adds a control
> plane on Microsoft Agent Framework, published as NuGet packages that run
> inside your own ASP.NET Core application.
>
> Page: https://tracon.dev/api/tracon.testing.contracts.storage.toolinvocationcontract/
> Summary: ToolInvocationContract: Behavior tests for the IRunStore tool-invocation contract.
Behavior tests for the [IRunStore](/api/tracon.irunstore/) tool-invocation contract.
```csharp
public abstract class ToolInvocationContract : TenantIsolationContract, IAsyncLifetime, IAsyncDisposable
```
## Remarks
Every implementation must pass the same scenarios; the summary is
computed *in the store itself*, not by fetching rows and
aggregating them in memory.
## Constructors
### ToolInvocationContract\(\)
```csharp
protected ToolInvocationContract()
```
## Methods
### A\_late\_settlement\_does\_not\_count\_as\_a\_second\_call\(\)
```csharp
[Fact]
public Task A_late_settlement_does_not_count_as_a_second_call()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### A\_late\_settlement\_never\_erases\_a\_measurement\_the\_row\_already\_carries\(\)
```csharp
[Fact]
public Task A_late_settlement_never_erases_a_measurement_the_row_already_carries()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### A\_measurement\_that\_names\_no\_provider\_or\_model\_comes\_back\_with\_none\(\)
```csharp
[Fact]
public Task A_measurement_that_names_no_provider_or_model_comes_back_with_none()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### A\_second\_late\_settlement\_for\_the\_same\_call\_changes\_nothing\(\)
```csharp
[Fact]
public Task A_second_late_settlement_for_the_same_call_changes_nothing()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### CancellableWriteAsync\(CancellationToken\)
Calls one **write** method of the store with the given
token.
```csharp
protected override ValueTask CancellableWriteAsync(CancellationToken cancellationToken)
```
#### Parameters
`cancellationToken` [CancellationToken](https://learn.microsoft.com/dotnet/api/system.threading.cancellationtoken)
The token the store must observe.
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask)
The completion task.
#### Remarks
The write must be one [StoreCancellationContract.WroteAnythingAsync](/api/tracon.testing.contracts.storage/) can see. A write
this contract cannot read back proves nothing about side effects, which
is why [StoreCancellationContract.The_write_this_contract_checks_can_be_read_back](/api/tracon.testing.contracts.storage/)
runs the same pair with a live token and requires the read to find it.
### CountAsync\(string, CancellationToken\)
Reports how many records the given tenant sees through the listing endpoint.
```csharp
protected override ValueTask CountAsync(string tenantId, CancellationToken cancellationToken)
```
#### Parameters
`tenantId` [string](https://learn.microsoft.com/dotnet/api/system.string)
The reading tenant.
`cancellationToken` [CancellationToken](https://learn.microsoft.com/dotnet/api/system.threading.cancellationtoken)
The token every store call inside the hook must be handed; see
[TenantIsolationContract.SeedAsync](/api/tracon.testing.contracts.storage/).
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask\-1)<[int](https://learn.microsoft.com/dotnet/api/system.int32)\>
The number of records seen.
### ExistsAsync\(string, object\)
Reports whether the record is visible from the given tenant's viewpoint.
```csharp
protected override ValueTask ExistsAsync(string tenantId, object key)
```
#### Parameters
`tenantId` [string](https://learn.microsoft.com/dotnet/api/system.string)
The reading tenant.
`key` [object](https://learn.microsoft.com/dotnet/api/system.object)
The key returned by [TenantIsolationContract.SeedAsync](/api/tracon.testing.contracts.storage/).
#### Returns
[ValueTask](https://learn.microsoft.com/dotnet/api/system.threading.tasks.valuetask\-1)<[bool](https://learn.microsoft.com/dotnet/api/system.boolean)\>
[true](https://learn.microsoft.com/dotnet/csharp/language-reference/builtin-types/bool) if the record is visible.
### Failed\_invocation\_is\_counted\_as\_unsuccessful\(\)
```csharp
[Fact]
public Task Failed_invocation_is_counted_as_unsuccessful()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Invocation\_fields\_round\_trip\(\)
```csharp
[Fact]
public Task Invocation_fields_round_trip()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Invocation\_with\_no\_reported\_usage\_comes\_back\_with\_EMPTY\_usage\(\)
```csharp
[Fact]
public Task Invocation_with_no_reported_usage_comes_back_with_EMPTY_usage()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Invocations\_come\_back\_in\_time\_order\(\)
```csharp
[Fact]
public Task Invocations_come_back_in_time_order()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Late\_settlement\_fills\_in\_the\_timed\_out\_record\_without\_rewriting\_what\_the\_model\_was\_told\(\)
```csharp
[Fact]
public Task Late_settlement_fills_in_the_timed_out_record_without_rewriting_what_the_model_was_told()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Late\_settlement\_for\_an\_unknown\_call\_reports\_that\_it\_wrote\_nothing\(\)
```csharp
[Fact]
public Task Late_settlement_for_an_unknown_call_reports_that_it_wrote_nothing()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Late\_settlement\_from\_the\_wrong\_tenant\_writes\_nothing\(\)
```csharp
[Fact]
public Task Late_settlement_from_the_wrong_tenant_writes_nothing()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Late\_settlement\_touches\_only\_the\_call\_it\_names\(\)
```csharp
[Fact]
public Task Late_settlement_touches_only_the_call_it_names()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### Non\_token\_measurement\_round\_trips\(\)
```csharp
[Fact]
public Task Non_token_measurement_round_trips()
```
#### Returns
[Task](https://learn.microsoft.com/dotnet/api/system.threading.tasks.task)
### SeedAsync\(string, string, CancellationToken\)
Writes a sample record for the given tenant.
```csharp
protected override ValueTask