---
title: "Tool Classification"
description: "The tool confidence level of each tool of Slint SC, and how it is reached."
---
**Addresses:** ISO 26262-8 11.4.5

This chapter classifies each tool whose failure could introduce an error into the product, or hide one.

## Summary

The classes are Tool Impact (TI), Tool error Detection (TD), and the resulting Tool Confidence Level (TCL).

| Tool | Ships | TI | TD | TCL | Qualified by |
| --- | --- | --- | --- | --- | --- |
| [Slint compiler](#slint-compiler) | No | TI2 | TD1 | TCL1 | Not required |
| [slint-sc-coverage](#slint-sc-coverage) | No | TI2 | TD3 | TCL3 | [Validation](/evaluation-report/qualification-method/#slint-sc-coverage) |
| [slint-sc runtime](#slint-sc-runtime) | Yes | Not a tool | | | [Component qualification](/qualification-plan/component-qualification/) |

## Slint Compiler

The `slint-compiler` translates `.slint` files into Rust code that is compiled into the final executable.

* **Tool Impact (TI2):** The `slint-compiler` can introduce errors into the executable.
* **Tool Error Detection (TD1):** The generated code is part of the customer's application, which is developed and verified in accordance with ISO 26262.
  That verification detects an error the `slint-compiler` introduces, as in ISO 26262-8 11.4.5.2 Example 1.
* **Tool Confidence Level (TCL1):** The combination of TI2 and TD1 results in a Tool Confidence Level of TCL1.
* **Qualification Strategy:** A tool classified at TCL1 needs no qualification methods, per ISO 26262-8 11.4.6.1.

## slint-sc-coverage

`slint-sc-coverage` reports which parts of the `.slint` code the tests reached, from the map the Slint SC compiler writes and LLVM's coverage of the generated code,
see [Coverage of Slint Code](/user-manual/slint-coverage/).
It doesn't ship, and its output is evidence: a report of coverage that wasn't achieved hides untested code.

* **Tool Impact (TI2):** the tool can fail to detect an error, by reporting a point as reached that wasn't, or by leaving a point out.
* **Tool Error Detection (TD3):** nothing in the customer's process checks the report against the coverage the tests actually reached.
* **Tool Confidence Level (TCL3):** the combination of TI2 and TD3 results in a Tool Confidence Level of TCL3.
* **Qualification Strategy:** the tool is qualified with the methods of ISO 26262-8 Table 4.
  Runtime test cases state their expected coverage in the source and fail on any difference, on every run;
  see [Qualification Method](/evaluation-report/qualification-method/#slint-sc-coverage).

## slint-sc Runtime

The runtime is not a tool.
It ships inside the customer's binary, so it is qualified as a software component under ISO 26262-8 Clause 12 and carries no tool confidence level.
See the [Component Qualification Plan](/qualification-plan/component-qualification/).