> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/Effect-TS/tsgo/llms.txt
> Use this file to discover all available pages before exploring further.

# Diagnostic severity

> Understand severity levels and learn how to override them globally with diagnosticSeverity or per-line with directive comments.

Every Effect diagnostic has a default severity that determines how it appears in your editor and whether it affects `tsc`'s exit code. You can override any diagnostic's severity globally in `tsconfig.json` or locally using directive comments.

## Severity levels

| Level        | Symbol | Meaning                                                         |
| ------------ | ------ | --------------------------------------------------------------- |
| `error`      | ❌      | A hard error. Breaks the `tsc` exit code by default.            |
| `warning`    | ⚠️     | A warning. Visible in editors; does not break `tsc` by default. |
| `suggestion` | 💡     | A code suggestion. Shown as a hint in editors.                  |
| `message`    | 💬     | An informational message. Lowest visible severity.              |
| `off`        | ➖      | Disabled. The diagnostic is not reported at all.                |

<Note>
  Diagnostics marked `➖` in the diagnostics table are **off by default**. You must explicitly set them in `diagnosticSeverity` to enable them.
</Note>

## Global severity overrides

Use the `diagnosticSeverity` plugin option in `tsconfig.json` to override the default severity for any rule.

```jsonc tsconfig.json theme={null}
{
  "compilerOptions": {
    "plugins": [
      {
        "name": "@effect/language-service",
        "diagnosticSeverity": {
          // Enable an off-by-default rule at warning severity
          "strictEffectProvide": "warning",
          // Downgrade an error to a warning
          "floatingEffect": "warning",
          // Silence a rule entirely
          "catchUnfailableEffect": "off"
        }
      }
    ]
  }
}
```

### Common patterns

**Enable an off-by-default rule**

Rules default to `off` when they are opinionated or project-specific. Enable them by assigning any active severity:

```jsonc theme={null}
"diagnosticSeverity": {
  "globalFetch": "warning",
  "nodeBuiltinImport": "suggestion"
}
```

**Downgrade an error to a warning**

Useful when adopting a new diagnostic incrementally:

```jsonc theme={null}
"diagnosticSeverity": {
  "missingEffectError": "warning"
}
```

**Disable a built-in rule**

```jsonc theme={null}
"diagnosticSeverity": {
  "effectGenUsesAdapter": "off"
}
```

## Exit code control

By default, only error-severity diagnostics affect `tsc`'s exit code. Use these options to adjust that behaviour:

<AccordionGroup>
  <Accordion title="ignoreEffectSuggestionsInTscExitCode (default: true)">
    When `true`, Effect diagnostics at `suggestion` or `message` severity do not cause a non-zero `tsc` exit code. Diagnostics are still reported; they just won't fail CI.

    Set to `false` if you want suggestions to be treated as build failures:

    ```jsonc theme={null}
    "ignoreEffectSuggestionsInTscExitCode": false
    ```
  </Accordion>

  <Accordion title="ignoreEffectWarningsInTscExitCode (default: false)">
    When `true`, Effect diagnostics at `warning` severity do not cause a non-zero `tsc` exit code. Useful when you want warning-level feedback in your editor without blocking CI.

    ```jsonc theme={null}
    "ignoreEffectWarningsInTscExitCode": true
    ```
  </Accordion>

  <Accordion title="ignoreEffectErrorsInTscExitCode (default: false)">
    When `true`, Effect error-severity diagnostics do not cause a non-zero `tsc` exit code. This lets you run `tsc` in check mode without blocking on Effect-specific errors.

    ```jsonc theme={null}
    "ignoreEffectErrorsInTscExitCode": true
    ```
  </Accordion>
</AccordionGroup>

## Directive comments

You can override diagnostic severity for a specific block or line using directive comments, without touching `tsconfig.json`.

### Block-level: `@effect-diagnostics`

A `@effect-diagnostics` comment applies until it is overridden by another directive or the end of the file.

```typescript theme={null}
// @effect-diagnostics floatingEffect:off
const ignored = Effect.succeed(42) // not reported

// @effect-diagnostics floatingEffect:error
const alsoIgnored = Effect.succeed(42) // reported again
```

You can combine multiple rules in a single directive:

```typescript theme={null}
// @effect-diagnostics floatingEffect:off missingEffectError:warning
```

### Line-level: `@effect-diagnostics-next-line`

A `@effect-diagnostics-next-line` comment applies only to the immediately following line.

```typescript theme={null}
// @effect-diagnostics-next-line floatingEffect:off
const temporary = Effect.succeed(42) // not reported for this line only
const reported = Effect.succeed(42) // back to default
```

<Tip>
  Your editor will offer completion suggestions for both directive forms, including available rule names and severity values.
</Tip>

## Directive-based enabling with `skipDisabledOptimization`

By default, globally disabled diagnostics are skipped entirely during analysis for performance. This means `@effect-diagnostics` directives **cannot re-enable** a rule that has `"off"` in `diagnosticSeverity`.

Set `skipDisabledOptimization: true` to process all diagnostics regardless of their global setting, allowing directive comments to re-enable individual rules on a per-section basis:

```jsonc tsconfig.json theme={null}
{
  "compilerOptions": {
    "plugins": [
      {
        "name": "@effect/language-service",
        "diagnosticSeverity": {
          "globalFetch": "off"
        },
        "skipDisabledOptimization": true
      }
    ]
  }
}
```

```typescript theme={null}
// @effect-diagnostics globalFetch:warning
fetch("/api/data") // reported as warning

// @effect-diagnostics globalFetch:off
fetch("/api/other") // silenced again
```

<Warning>
  Enabling `skipDisabledOptimization` increases analysis time proportional to the number of disabled rules. Only enable it when you actively use directive-based overrides for globally disabled diagnostics.
</Warning>