# Tagging

When you have big circuits, keeping track of which node corresponds to which part of your code becomes difficult. A tagging system can simplify such situations:

```python
def g(z):
    with fhe.tag("def"):
        a = 120 - z
        b = a // 4
    return b


def f(x):
    with fhe.tag("abc"):
        x = x * 2
        with fhe.tag("foo"):
            y = x + 42
        z = np.sqrt(y).astype(np.int64)

    return g(z + 3) * 2
```

When you compile `f` with inputset of `range(10)`, you get the following graph:

```
 %0 = x                            # EncryptedScalar<uint4>        ∈ [0, 9]
 %1 = 2                            # ClearScalar<uint2>            ∈ [2, 2]            @ abc
 %2 = multiply(%0, %1)             # EncryptedScalar<uint5>        ∈ [0, 18]           @ abc
 %3 = 42                           # ClearScalar<uint6>            ∈ [42, 42]          @ abc.foo
 %4 = add(%2, %3)                  # EncryptedScalar<uint6>        ∈ [42, 60]          @ abc.foo
 %5 = subgraph(%4)                 # EncryptedScalar<uint3>        ∈ [6, 7]            @ abc
 %6 = 3                            # ClearScalar<uint2>            ∈ [3, 3]
 %7 = add(%5, %6)                  # EncryptedScalar<uint4>        ∈ [9, 10]
 %8 = 120                          # ClearScalar<uint7>            ∈ [120, 120]        @ def
 %9 = subtract(%8, %7)             # EncryptedScalar<uint7>        ∈ [110, 111]        @ def
%10 = 4                            # ClearScalar<uint3>            ∈ [4, 4]            @ def
%11 = floor_divide(%9, %10)        # EncryptedScalar<uint5>        ∈ [27, 27]          @ def
%12 = 2                            # ClearScalar<uint2>            ∈ [2, 2]
%13 = multiply(%11, %12)           # EncryptedScalar<uint6>        ∈ [54, 54]
return %13

Subgraphs:

    %5 = subgraph(%4):

        %0 = input                         # EncryptedScalar<uint2>          @ abc.foo
        %1 = sqrt(%0)                      # EncryptedScalar<float64>        @ abc
        %2 = astype(%1, dtype=int_)        # EncryptedScalar<uint1>          @ abc
        return %2
```

If you get an error, you'll see exactly where the error occurred (e.g., which layer of the neural network, if you tag layers).

{% hint style="info" %}
In the future, we plan to use tags for additional features (e.g., to measure performance of tagged regions), so it's a good idea to start utilizing them for big circuits.
{% endhint %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.zama.org/concrete/2.4/tutorials/tagging.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.