IToolArgumentsValidator

Namespace Tracon · Assembly Tracon.Abstractions.dll

Validates a tool call’s arguments before the call runs.

public interface IToolArgumentsValidator

Remarks

Binding a call’s JSON arguments onto AI.AIFunctionArguments already rejects a type mismatch, a missing required field, or an invalid enum value — but it never rejects an extra field the schema does not declare, and a hand-written AI.AIFunction or an MCP-sourced tool shares none of that behavior. This interface is the consumer’s own gate on top of binding, applied uniformly to every tool source.

The default implementation is a no-op (registered with TryAddSingleton), so an installation that registers nothing keeps today’s behavior exactly. A consumer replaces the registration to enforce its own rule; Tracon does not ship a built-in JSON Schema validator — validation stays inside the consumer’s own trust boundary.

If this validator throws, the call is rejected (fail-closed). A gate that fails open on an exception is not a gate.

Tenant mode: IToolArgumentsValidator.ValidateAsync carries no tenant parameter — no delivery guarantee applies to the call it makes (it runs synchronously, inline, exactly once per tool call attempt; the validator is never queued or retried by Tracon itself). A multi-tenant implementation reads the ambient tenant itself, the same way the tool authorization wrapper reads it for IToolAuthorizationHandler.

Methods

ValidateAsync(ToolDescriptor, AIFunctionArguments, CancellationToken)

Validates the arguments of one call before it runs.

ValueTask<ToolArgumentsValidationResult> ValidateAsync(ToolDescriptor tool, AIFunctionArguments arguments, CancellationToken cancellationToken = default)

Parameters

tool ToolDescriptor

The tool being called.

arguments AIFunctionArguments

The call’s bound arguments.

cancellationToken CancellationToken

The cancellation token.

Returns

ValueTask<ToolArgumentsValidationResult>

The validation outcome.