What causes "no input with name '%s' was found" in microsoft/aspire?

Correct the input name string to match a declared input exactly (names are case-sensitive)

no input with name ' ' was found

Error message

no input with name '%s' was found

What it means

Generated Go ATS wrapper code's Required(name) method looks up an interaction input by name; if Get succeeds but the input is absent (or nil), it returns this error. It exists to distinguish 'the name exists but is empty' from a successful lookup, guaranteeing Required never returns a nil input.

Solutions

Correct the input name string to match a declared input exactly (names are case-sensitive)
Regenerate the Go client from the current AppHost so the inputs struct is in sync with the capability definition
Use Get/Value instead of Required if the input is genuinely optional

Example fix

// before
val, err := inputs.Required("ConenctionString") // typo
// after
val, err := inputs.Required("ConnectionString")

Defensive patterns

Strategy: try-catch

Validate before calling

// Check availability first
if v, err := inputs.Get("ConnectionString"); err != nil || v == nil {
	// handle missing input before calling Required
}

Type guard

func inputExists(inputs *InteractionInputs, name string) bool { v, _ := inputs.Get(name); return v != nil }

Try / catch

val, err := inputs.Required("ConnectionString")
if err != nil {
	return fmt.Errorf("missing required input: %w", err)
}

Prevention

Copy input names from the generated source rather than typing them
Regenerate the Go client whenever the AppHost inputs change
Only use Required for inputs that are unconditionally declared

When it happens

Trigger: Calling a generated Required("name") method on the interaction-inputs struct with a name that was never declared among the capability's inputs, or whose lookup returned a nil entry.

Common situations: Typo in the input name, renaming/removing an input on the C# side while the generated Go client is stale, or consuming a required input that is only conditionally defined.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of microsoft/aspire@25830f84bd (2026-09-16). Data as JSON: /api/errors/0b3aba081fc1abb3. Report an issue: GitHub.

Appendix: source

Thrown at src/Aspire.Hosting.CodeGeneration.Go/AtsGoCodeGenerator.cs:997

        // These delegate to ToArray (a single RPC) and then match locally. Names are compared
        // case-insensitively via strings.EqualFold to mirror StringComparers.InteractionInputName in .NET.
        WriteLine("// Get returns the input with the specified name, or nil if no input matches.");
        WriteLine($"func (s *{implName}) Get(name string) (*InteractionInput, error) {{");
        WriteLine("\tif s.err != nil { return nil, s.err }");
        WriteLine("\tinputs, err := s.ToArray()");
        WriteLine("\tif err != nil { return nil, err }");
        WriteLine("\tfor _, input := range inputs {");
        WriteLine("\t\tif strings.EqualFold(input.Name, name) { return input, nil }");
        WriteLine("\t}");
        WriteLine("\treturn nil, nil");
        WriteLine("}");
        WriteLine();

        WriteLine("// Required returns the input with the specified name, or an error if no input matches.");
        WriteLine($"func (s *{implName}) Required(name string) (*InteractionInput, error) {{");
        WriteLine("\tinput, err := s.Get(name)");
        WriteLine("\tif err != nil { return nil, err }");
        WriteLine("\tif input == nil { return nil, fmt.Errorf(\"no input with name '%s' was found\", name) }");
        WriteLine("\treturn input, nil");
        WriteLine("}");
        WriteLine();

        WriteLine("// Value returns the value of the input with the specified name, or an empty string if no input matches or it has no value.");
        WriteLine($"func (s *{implName}) Value(name string) (string, error) {{");
        WriteLine("\tinput, err := s.Get(name)");
        WriteLine("\tif err != nil { return \"\", err }");
        WriteLine("\tif input == nil || input.Value == nil { return \"\", nil }");
        WriteLine("\treturn *input.Value, nil");
        WriteLine("}");
        WriteLine();

        WriteLine("// RequiredValue returns the value of the input with the specified name, or an error if no input matches.");
        WriteLine($"func (s *{implName}) RequiredValue(name string) (string, error) {{");
        WriteLine("\tinput, err := s.Required(name)");
        WriteLine("\tif err != nil { return \"\", err }");
        WriteLine("\tif input.Value == nil { return \"\", nil }");

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