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<h1 class="menu-title">towl Documentation</h1>
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<h1 id="config"><a class="header" href="#config">Config</a></h1>
<p>The config module loads settings from <code>.towl.toml</code>, merges environment variables, and provides the <code>init</code> command for generating default configuration.</p>
<h2 id="towlconfig"><a class="header" href="#towlconfig"><code>TowlConfig</code></a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub struct TowlConfig {
pub parsing: ParsingConfig,
pub github: GitHubConfig,
pub llm: LlmConfig,
}
<span class="boring">}</span></code></pre></pre>
<h3 id="towlconfigload"><a class="header" href="#towlconfigload"><code>TowlConfig::load</code></a></h3>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>impl TowlConfig {
pub fn load(path: Option<&PathBuf>) -> Result<Self, TowlConfigError>;
}
<span class="boring">}</span></code></pre></pre>
<p>Loads configuration with this precedence:</p>
<ol>
<li>Built-in defaults</li>
<li>Config file resolved as: explicit <code>path</code> argument > <code>TOWL_CONFIG</code> env var > <code>.towl.toml</code></li>
<li>Git remote auto-detection for owner/repo</li>
<li>Environment variable overrides (<code>TOWL_GITHUB_*</code>, <code>TOWL_LLM_*</code>)</li>
</ol>
<p>If no config file exists, defaults are used without error.</p>
<h3 id="init"><a class="header" href="#init"><code>init</code></a></h3>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub async fn init(path: &Path, force: bool) -> Result<(), TowlConfigError>
<span class="boring">}</span></code></pre></pre>
<p>Creates a <code>.towl.toml</code> file at the given path. Validates that a GitHub git remote exists but does not write owner/repo to the file (they are always detected at runtime).</p>
<ul>
<li>Fails if the file already exists (unless <code>force</code> is <code>true</code>)</li>
<li>Validates the path for traversal attacks</li>
<li>Serializes <code>ParsingConfig</code> and <code>LlmConfig</code> defaults to TOML</li>
</ul>
<h2 id="parsingconfig"><a class="header" href="#parsingconfig"><code>ParsingConfig</code></a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub struct ParsingConfig {
pub file_extensions: HashSet<String>,
pub exclude_patterns: Vec<String>,
pub include_context_lines: usize,
pub comment_prefixes: Vec<String>,
pub todo_patterns: Vec<String>,
pub function_patterns: Vec<String>,
}
<span class="boring">}</span></code></pre></pre>
<p>All fields have defaults via <code>#[serde(default)]</code>:</p>
<div class="table-wrapper"><table><thead><tr><th>Field</th><th>Default</th></tr></thead><tbody>
<tr><td><code>file_extensions</code></td><td><code>rs</code>, <code>toml</code>, <code>json</code>, <code>yaml</code>, <code>yml</code>, <code>sh</code>, <code>bash</code></td></tr>
<tr><td><code>exclude_patterns</code></td><td><code>target/*</code>, <code>.git/*</code></td></tr>
<tr><td><code>include_context_lines</code></td><td><code>10</code></td></tr>
<tr><td><code>comment_prefixes</code></td><td><code>//</code>, <code>^\s*#</code>, <code>/\*</code>, <code>^\s*\*</code></td></tr>
<tr><td><code>todo_patterns</code></td><td><code>TODO:</code>, <code>FIXME:</code>, <code>HACK:</code>, <code>NOTE:</code>, <code>BUG:</code> (case-insensitive)</td></tr>
<tr><td><code>function_patterns</code></td><td>Rust, Python, JS, Java/C#, Go patterns</td></tr>
</tbody></table>
</div>
<p>Each pattern array is limited to <code>MAX_CONFIG_PATTERNS</code> (100) entries.</p>
<h2 id="githubconfig"><a class="header" href="#githubconfig"><code>GitHubConfig</code></a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub struct GitHubConfig {
pub token: SecretString,
pub owner: Owner,
pub repo: Repo,
pub rate_limit_delay_ms: u64,
}
<span class="boring">}</span></code></pre></pre>
<ul>
<li><code>token</code> is stored as <code>secrecy::SecretString</code> and masked in debug/display output</li>
<li><code>owner</code> and <code>repo</code> are auto-detected from <code>git remote get-url origin</code> at runtime (not serialised to config)</li>
<li><code>rate_limit_delay_ms</code> adds a delay between GitHub API calls (default: 1000ms)</li>
</ul>
<h3 id="environment-variable-overrides"><a class="header" href="#environment-variable-overrides">Environment Variable Overrides</a></h3>
<div class="table-wrapper"><table><thead><tr><th>Variable</th><th>Overrides</th></tr></thead><tbody>
<tr><td><code>TOWL_CONFIG</code></td><td><code>DEFAULT_CONFIG_PATH</code> (overridden by explicit <code>path</code> argument)</td></tr>
<tr><td><code>TOWL_GITHUB_TOKEN</code></td><td>-- (env-only)</td></tr>
<tr><td><code>TOWL_GITHUB_OWNER</code></td><td>git remote detection</td></tr>
<tr><td><code>TOWL_GITHUB_REPO</code></td><td>git remote detection</td></tr>
</tbody></table>
</div>
<h2 id="owner--repo"><a class="header" href="#owner--repo"><code>Owner</code> / <code>Repo</code></a></h2>
<p>Validated newtype wrappers providing type safety:</p>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub struct Owner(String);
pub struct Repo(String);
<span class="boring">}</span></code></pre></pre>
<h3 id="try_new"><a class="header" href="#try_new"><code>try_new</code></a></h3>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub fn try_new(s: impl Into<String>) -> Result<Self, TowlConfigError>
<span class="boring">}</span></code></pre></pre>
<p>Constructs a new <code>Owner</code> or <code>Repo</code>, rejecting values exceeding <code>MAX_CONFIG_STRING_LENGTH</code> (512 characters).</p>
<p><strong>Errors:</strong></p>
<ul>
<li><code>ConfigValueTooLong</code> -- Value exceeds 512 characters</li>
</ul>
<p>Both also implement:</p>
<ul>
<li><code>Display</code>, <code>Default</code>, <code>Debug</code>, <code>Clone</code>, <code>PartialEq</code>, <code>Eq</code></li>
<li><code>Serialize</code>, <code>Deserialize</code></li>
</ul>
<h2 id="llmconfig"><a class="header" href="#llmconfig"><code>LlmConfig</code></a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub struct LlmConfig {
pub provider: String,
pub model: String,
pub base_url: Option<String>,
pub api_key: SecretString,
pub max_concurrent_analyses: usize,
pub max_analyse_count: usize,
pub max_tokens: u32,
pub max_retries: usize,
pub command: Option<String>,
pub args: Option<Vec<String>>,
}
<span class="boring">}</span></code></pre></pre>
<ul>
<li><code>api_key</code> is stored as <code>secrecy::SecretString</code> and masked in debug output (env-only via <code>TOWL_LLM_API_KEY</code>)</li>
<li><code>provider</code> selects the LLM backend: <code>"claude"</code>, <code>"openai"</code>, <code>"claude-code"</code>, or <code>"codex"</code></li>
<li><code>command</code> and <code>args</code> allow overriding the CLI binary path and arguments for CLI providers</li>
</ul>
<div class="table-wrapper"><table><thead><tr><th>Field</th><th>Default</th></tr></thead><tbody>
<tr><td><code>provider</code></td><td><code>"claude"</code></td></tr>
<tr><td><code>model</code></td><td><code>"claude-opus-4-6"</code></td></tr>
<tr><td><code>base_url</code></td><td><code>None</code> (provider default)</td></tr>
<tr><td><code>max_concurrent_analyses</code></td><td><code>5</code></td></tr>
<tr><td><code>max_analyse_count</code></td><td><code>50</code></td></tr>
<tr><td><code>max_tokens</code></td><td><code>4096</code></td></tr>
<tr><td><code>max_retries</code></td><td><code>3</code></td></tr>
</tbody></table>
</div>
<h3 id="environment-variable-overrides-1"><a class="header" href="#environment-variable-overrides-1">Environment Variable Overrides</a></h3>
<div class="table-wrapper"><table><thead><tr><th>Variable</th><th>Overrides</th></tr></thead><tbody>
<tr><td><code>TOWL_LLM_API_KEY</code></td><td>-- (env-only)</td></tr>
<tr><td><code>TOWL_LLM_PROVIDER</code></td><td><code>llm.provider</code></td></tr>
<tr><td><code>TOWL_LLM_MODEL</code></td><td><code>llm.model</code></td></tr>
<tr><td><code>TOWL_LLM_BASE_URL</code></td><td><code>llm.base_url</code></td></tr>
</tbody></table>
</div>
<h2 id="gitrepoinfo-internal"><a class="header" href="#gitrepoinfo-internal"><code>GitRepoInfo</code> (internal)</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub(crate) struct GitRepoInfo {
pub owner: Owner,
pub repo: Repo,
}
<span class="boring">}</span></code></pre></pre>
<h3 id="from_path"><a class="header" href="#from_path"><code>from_path</code></a></h3>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub(crate) async fn from_path<P: AsRef<Path>>(path: P) -> Result<Self, TowlConfigError>
<span class="boring">}</span></code></pre></pre>
<p>Internal function that discovers the git remote URL by running <code>git remote get-url origin</code> and parses the owner and repo name. Supports both HTTPS and SSH URL formats. Not part of the public API.</p>
<p><strong>Errors:</strong></p>
<ul>
<li><code>GitRepoNotFound</code> -- Not inside a git repository</li>
<li><code>GitRemoteNotFound</code> -- No <code>origin</code> remote configured</li>
<li><code>GitInvalidUrl</code> -- Could not parse owner/repo from the URL</li>
</ul>
<h2 id="errors"><a class="header" href="#errors">Errors</a></h2>
<pre><pre class="playground"><code class="language-rust"><span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>pub enum TowlConfigError {
PathTraversalAttempt(PathBuf),
ConfigAlreadyExists(PathBuf),
WriteToFileError(PathBuf, std::io::Error),
UnableToParseToml(toml::ser::Error),
CouldNotCreateConfig(ConfigError),
GitRepoNotFound { message: String },
GitRemoteNotFound { message: String },
GitInvalidUrl { url: String, message: String },
TooManyConfigPatterns { field: String, count: usize, max_allowed: usize },
ConfigValueTooLong { field: String, length: usize, max_length: usize },
ContextLinesOutOfRange { value: usize, min: usize, max: usize },
}
<span class="boring">}</span></code></pre></pre>
<h2 id="constants"><a class="header" href="#constants">Constants</a></h2>
<div class="table-wrapper"><table><thead><tr><th>Constant</th><th>Value</th><th>Purpose</th></tr></thead><tbody>
<tr><td><code>DEFAULT_CONFIG_PATH</code></td><td><code>.towl.toml</code></td><td>Default config file name</td></tr>
<tr><td><code>MAX_CONFIG_PATTERNS</code></td><td>100</td><td>Maximum entries per pattern array</td></tr>
<tr><td><code>MAX_CONFIG_STRING_LENGTH</code></td><td>512</td><td>Maximum length for any single config string</td></tr>
<tr><td><code>MIN_CONTEXT_LINES</code></td><td>1</td><td>Minimum <code>include_context_lines</code> value</td></tr>
<tr><td><code>MAX_CONTEXT_LINES</code></td><td>50</td><td>Maximum <code>include_context_lines</code> value</td></tr>
</tbody></table>
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