> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sifr.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# SIFR-CALL-0005: Callable arity failure or expression is not callable.

> Callable arity failure or expression is not callable.

`SIFR-CALL-0005` belongs to the **Function and method calls** diagnostic family. It means: callable arity failure or expression is not callable.

## Why It Happens

The call site does not match the callable signature Sifr inferred or checked. Fix the number of arguments, names, types, or overload selection.

<Info>
  Use `sifr --explain SIFR-CALL-0005` locally to see the renderer's exact message template and any machine-applicable suggestions for the compiler version you are running.
</Info>

## Erroneous Code

```python theme={null}
def greet(name: str) -> str:
    return "hi " + name

message = greet()
```

## How To Fix It

Make the call match the function signature: provide required arguments once, use known keyword names, and call only callable values.

## Fixed Code

```python theme={null}
def greet(name: str) -> str:
    return "hi " + name

message = greet("Sifr")
```

## Details

| Field                  | Value                                                         |
| ---------------------- | ------------------------------------------------------------- |
| Code                   | `SIFR-CALL-0005`                                              |
| Family                 | `CALL`                                                        |
| Severity               | Error                                                         |
| Stability              | stable                                                        |
| Owner                  | `sifr_lowering::lower`                                        |
| Representative fixture | `crates/sifr/tests/e2e/fail/map_callable_arity_mismatch.sifr` |

See the [Error Codes index](/diagnostics/error-codes) for the complete catalog.