ToolResult

NexusLabs.Needlr.AgentFramework

NexusLabs.Needlr.AgentFramework.Tools

ToolResult Class

Static factory providing shorthand constructors for ToolResult<TValue,TError> using the default ToolError shape.

public static class ToolResult

Inheritance System.Object 🡒 ToolResult

Methods

ToolResult.Fail<TValue,TError>(TError, Exception, Nullable<bool>) Method

Creates a failure ToolResult<TValue,TError> with a custom error shape.

public static NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,TError> Fail<TValue,TError>(TError error, System.Exception? ex=null, System.Nullable<bool> isTransient=null)
    where TError : class;

Type parameters

TValue

TError

Parameters

error TError

ex System.Exception

isTransient System.Nullable<System.Boolean>

Returns

NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,TError>

ToolResult.Fail<TValue>(string, Exception, Nullable<bool>, string) Method

Creates a failure ToolResult<TValue,TError> from a message string.

public static NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,NexusLabs.Needlr.AgentFramework.Tools.ToolError> Fail<TValue>(string message, System.Exception? ex=null, System.Nullable<bool> isTransient=null, string? suggestion=null);

Type parameters

TValue

Parameters

message System.String

ex System.Exception

isTransient System.Nullable<System.Boolean>

suggestion System.String

Returns

NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,ToolError>

ToolResult.Ok<TValue>(TValue) Method

Creates a successful ToolResult<TValue,TError>.

public static NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,NexusLabs.Needlr.AgentFramework.Tools.ToolError> Ok<TValue>(TValue value);

Type parameters

TValue

Parameters

value TValue

Returns

NexusLabs.Needlr.AgentFramework.Tools.ToolResult<TValue,ToolError>

ToolResult.UnhandledFailure(Exception, Func<Exception,ToolError>) Method

Creates an IToolResult for an unhandled exception caught by middleware. IsTransient is null because middleware cannot determine whether the failure is transient without domain knowledge.

public static NexusLabs.Needlr.AgentFramework.Tools.IToolResult UnhandledFailure(System.Exception ex, System.Func<System.Exception,NexusLabs.Needlr.AgentFramework.Tools.ToolError>? formatter=null);

Parameters

ex System.Exception

The exception that escaped the tool body.

formatter System.Func<System.Exception,ToolError>

Optional formatter that converts the exception into the LLM-facing ToolError. When null, a default formatter is used that includes the exception type name without the message body.

Returns

IToolResult

Remarks

The default LLM-facing error message is "An unexpected error occurred ({ExceptionTypeName}). Please try again." — the type name is included so the model can distinguish a shape mismatch from a timeout from an authorization failure and choose a sensible recovery strategy. The System.Exception.Message body is intentionally \<em>not\</em> included to avoid leaking application or PII details (DB connection strings, user data, internal IDs). Pass formatter to override the LLM-facing message — useful when an application wants to keep the bland legacy message or surface domain-specific guidance.