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

# Configuring a project

> Map files to rule packs and tune evaluation behavior with .vectorlint.ini.

`.vectorlint.ini` is VectorLint's project configuration file. It lives in your project root and controls three things: global behavior settings, where VectorLint looks for custom rules, and which rule packs run on which files.

Run `vectorlint init` to generate a starter file. You can edit it manually at any time.

## Global Settings

These settings apply to all evaluations in the project.

| Setting           | Type    | Default   | Description                                                                       |
| ----------------- | ------- | --------- | --------------------------------------------------------------------------------- |
| `RulesPath`       | string  | *(none)*  | Root directory for custom rule packs. If omitted, only built-in presets are used. |
| `Concurrency`     | integer | `4`       | Number of evaluations to run in parallel.                                         |
| `DefaultSeverity` | string  | `warning` | Severity level for reported violations: `warning` or `error`.                     |

```ini theme={null}
# .vectorlint.ini

RulesPath=.github/rules
Concurrency=4
DefaultSeverity=warning
```

## File Pattern Sections

Use `[glob/pattern]` sections to map file types to rule packs. Each section targets files matching the pattern and specifies which rules to run.

```ini theme={null}
[**/*.md]
RunRules=Acme

[content/docs/**/*.md]
RunRules=Acme
GrammarChecker.strictness=9
TechnicalAccuracy.threshold=8.0

[content/marketing/**/*.md]
RunRules=TechCorp
BrandVoice.strictness=8

[content/drafts/**/*.md]
RunRules=
```

### `RunRules`

A comma-separated list of rule pack names. Pack names correspond to subdirectory names inside `RulesPath`.

```ini theme={null}
RunRules=Acme, TechDocs
```

Set `RunRules=` with no value to explicitly skip all rules for matching files (useful for drafts or generated content).

## Rule Pack Directory Structure

The `RulesPath` setting defines where VectorLint looks for rule packs. Each subdirectory becomes an available pack name.

```
project/
├── .github/
│   └── rules/              ← RulesPath
│       ├── Acme/           ← Pack: "Acme"
│       │   ├── grammar.md
│       │   └── style.md
│       └── TechCorp/       ← Pack: "TechCorp"
│           └── brand.md
└── .vectorlint.ini
```

Rules inside `Acme/` are available when you set `RunRules=Acme`. Nesting is supported — you can organize rules into subdirectories within a pack.

## Cascading Configuration

VectorLint applies configuration blocks from general to specific, similar to Vale's cascade behavior. All blocks that match a given file are applied; more specific patterns override settings from more general ones, and rule packs accumulate.

```ini theme={null}
# Applied first — general
[**/*.md]
RunRules=GeneralRules
Grammar.strictness=5

# Applied second — more specific
# Result: runs GeneralRules AND TechDocs; strictness is 9 (overrides 5)
[content/docs/**/*.md]
RunRules=TechDocs
Grammar.strictness=9
```

**Specificity** is determined by path depth and wildcard count. `content/docs/**/*.md` is more specific than `**/*.md`.

## Strictness Overrides

You can tune how harshly individual check rules score content on a per-pattern basis.

```ini theme={null}
[pattern]
RuleID.strictness=value
```

Strictness controls the penalty weight applied to error density. Higher values penalize the same error rate more severely.

| Level    | Value    | Penalty per 1% error density | Typical use             |
| -------- | -------- | ---------------------------- | ----------------------- |
| Lenient  | `1`–`3`  | \~5 points                   | Drafts                  |
| Standard | `4`–`7`  | \~10 points                  | General content         |
| Strict   | `8`–`10` | \~20 points                  | Technical documentation |

You can use named levels (`lenient`, `standard`, `strict`) or direct numeric multipliers:

```ini theme={null}
[content/docs/**/*.md]
RunRules=Acme
GrammarChecker.strictness=strict
TechnicalAccuracy.strictness=20
```

## Complete Example

```ini theme={null}
# .vectorlint.ini

RulesPath=.github/rules
Concurrency=4
DefaultSeverity=warning

# All markdown files — baseline checks
[**/*.md]
RunRules=Acme
GrammarChecker.strictness=5

# Technical docs — stricter standards
[content/docs/**/*.md]
RunRules=Acme
GrammarChecker.strictness=9
TechnicalAccuracy.threshold=8.0

# Marketing — brand voice rules
[content/marketing/**/*.md]
RunRules=TechCorp
BrandVoice.strictness=8

# Drafts — skip all checks
[content/drafts/**/*.md]
RunRules=
```

## Global Style Guide (VECTORLINT.md)

In addition to `.vectorlint.ini`, you can place a `VECTORLINT.md` file in your project root to define global style instructions in plain language.

**Zero-config mode:** If no `.vectorlint.ini` exists, VectorLint automatically detects `VECTORLINT.md`, creates a synthetic "Style Guide Compliance" rule, and evaluates content against it.

**Combined mode:** When `.vectorlint.ini` is present, the contents of `VECTORLINT.md` are prepended to the system prompt for every evaluation — making your global tone and terminology preferences active across all rules.

<Note>
  Keep `VECTORLINT.md` concise. VectorLint emits a warning if the file exceeds approximately 4,000 tokens, as very large contexts can degrade evaluation quality and increase API costs.
</Note>

## Next Steps

* [LLM Providers](/llm-providers) — configure the model that runs evaluations
* [Style Guide](/style-guide) — write custom rules for your content standards