Add API docs to llms.txt file. (#766)

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Adds API docs to the llms.txt file for our agent to reference. Before,
it was not capturing this information about the API.

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----

> [!IMPORTANT]
> Adds OpenAPI documentation extraction and formatting to
`get-llm-text.ts` and updates Next.js configuration for ESLint and
OpenAPI file handling.
> 
>   - **Behavior**:
> - Adds `extractOpenAPIContent()` in `get-llm-text.ts` to extract
OpenAPI content from API pages.
> - Formats OpenAPI operations and specs using `formatOperation()` and
`formatOpenAPISpec()`.
> - Updates `getLLMText()` to return formatted OpenAPI content if
available.
>   - **Configuration**:
> - Changes `ignoreDuringBuilds` to `false` in `next.config.mjs` to
enable ESLint during builds.
> - Includes OpenAPI files in `outputFileTracingIncludes` for Vercel
deployments in `next.config.mjs`.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=stack-auth%2Fstack-auth&utm_source=github&utm_medium=referral)<sup>
for f3b3d75a35. You can
[customize](https://app.ellipsis.dev/stack-auth/settings/summaries) this
summary. It will automatically update as commits are pushed.</sup>

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---------

Co-authored-by: Konsti Wohlwend <n2d4xc@gmail.com>

docs/lib/get-llm-text.ts

@@ -1,5 +1,7 @@
+import { readFileSync } from 'fs';
 import type { InferPageType } from 'fumadocs-core/source';
 import { remarkInclude } from 'fumadocs-mdx/config';
+import { join } from 'path';
 import { remark } from 'remark';
 import remarkGfm from 'remark-gfm';
 import remarkMdx from 'remark-mdx';
@@ -11,8 +13,156 @@ const processor = remark()
   .use(remarkInclude)
   .use(remarkGfm);
 
+// Helper function to extract OpenAPI content
+function extractOpenAPIContent(page: InferPageType<typeof source> | InferPageType<typeof apiSource>): string | null {
+  const content = page.data.content;
+  
+  // Check if this is an API page with EnhancedAPIPage component
+  const enhancedAPIMatch = content.match(/<EnhancedAPIPage\s+([^>]+)\s*\/>/);
+  if (!enhancedAPIMatch) {
+    return null;
+  }
+  
+  // Extract document and operations from the component props
+  const propsString = enhancedAPIMatch[1];
+  const documentMatch = propsString.match(/document=\{?"([^"]+)"\}?/);
+  const operationsMatch = propsString.match(/operations=\{(\[.*?\])\}/);
+  
+  if (!documentMatch) {
+    return null;
+  }
+  
+  const documentPath = documentMatch[1];
+  
+  try {
+    // Load the OpenAPI spec file
+    // process.cwd() is already the docs directory, so just join with documentPath
+    const specPath = join(process.cwd(), documentPath);
+    const specContent = readFileSync(specPath, 'utf-8');
+    const spec = JSON.parse(specContent);
+    
+    let result = `# API Documentation: ${page.data.title}\n\n`;
+    result += `${page.data.description || ''}\n\n`;
+    
+    // If specific operations are specified, extract those
+    if (operationsMatch) {
+      try {
+        const operations = JSON.parse(operationsMatch[1]);
+        for (const op of operations) {
+          const pathItem = spec.paths?.[op.path];
+          const operation = pathItem?.[op.method.toLowerCase()];
+          
+          if (operation) {
+            result += formatOperation(op.path, op.method, operation);
+          }
+        }
+      } catch (e) {
+        if (e instanceof SyntaxError) {
+          // If parsing fails due to invalid JSON, include the whole spec summary
+          result += formatOpenAPISpec(spec);
+        } else {
+          console.error('Unexpected error parsing operations:', e);
+          result += formatOpenAPISpec(spec);
+        }
+      }
+    } else {
+      // Include the whole spec
+      result += formatOpenAPISpec(spec);
+    }
+    
+    return result;
+  } catch (error) {
+    if (error instanceof SyntaxError) {
+      console.error('JSON parsing error in OpenAPI spec:', documentPath, error);
+    } else if (error instanceof Error && 'code' in error && error.code === 'ENOENT') {
+      console.error('OpenAPI spec file not found:', documentPath, error);
+    } else {
+      console.error('Unexpected error reading OpenAPI spec:', documentPath, error);
+    }
+    return null;
+  }
+}
+
+// Helper function to format a single operation
+function formatOperation(path: string, method: string, operation: any): string {
+  let result = `## ${method.toUpperCase()} ${path}\n\n`;
+  
+  if (operation.summary) {
+    result += `**Summary:** ${operation.summary}\n\n`;
+  }
+  
+  if (operation.description) {
+    result += `**Description:** ${operation.description}\n\n`;
+  }
+  
+  // Parameters
+  if (operation.parameters && operation.parameters.length > 0) {
+    result += `**Parameters:**\n`;
+    for (const param of operation.parameters) {
+      result += `- \`${param.name}\` (${param.in}): ${param.description || 'No description'}\n`;
+    }
+    result += '\n';
+  }
+  
+  // Request body
+  if (operation.requestBody) {
+    result += `**Request Body:** ${operation.requestBody.description || 'Request body required'}\n\n`;
+  }
+  
+  // Responses
+  if (operation.responses) {
+    result += `**Responses:**\n`;
+    for (const [code, response] of Object.entries(operation.responses)) {
+      result += `- ${code}: ${(response as any).description || 'No description'}\n`;
+    }
+    result += '\n';
+  }
+  
+  return result;
+}
+
+// Helper function to format entire OpenAPI spec
+function formatOpenAPISpec(spec: any): string {
+  let result = '';
+  
+  if (spec.info) {
+    result += `**API Version:** ${spec.info.version}\n`;
+    if (spec.info.description) {
+      result += `**Description:** ${spec.info.description}\n`;
+    }
+    result += '\n';
+  }
+  
+  if (spec.paths) {
+    result += '**Available Endpoints:**\n\n';
+    const pathsMap = new Map<string, any>(Object.entries(spec.paths as Record<string, any>));
+    for (const [path, pathItem] of pathsMap) {
+      const methodsMap = new Map<string, any>(Object.entries(pathItem as Record<string, any>));
+      for (const [method, operation] of methodsMap) {
+        if (operation && typeof operation === 'object' && 'summary' in operation) {
+          result += `- ${method.toUpperCase()} ${path}: ${operation.summary}\n`;
+        }
+      }
+    }
+    result += '\n';
+  }
+  
+  return result;
+}
+
 export async function getLLMText(page: InferPageType<typeof source> | InferPageType<typeof apiSource>) {
   try {
+    // Check if this is an API page and extract OpenAPI content
+    const openAPIContent = extractOpenAPIContent(page);
+    if (openAPIContent) {
+      return `# ${page.data.title}
+URL: ${page.url}
+Source: ${page.data._file.absolutePath}
+
+${openAPIContent}`;
+    }
+    
+    // For non-API pages, process normally
     // Remove the Fumadocs generated comment before processing
     let content = page.data.content;
 

docs/next.config.mjs

@@ -7,7 +7,7 @@ const config = {
   reactStrictMode: true,
   eslint: {
     // Temporarily disable ESLint during builds for Vercel deployment
-    ignoreDuringBuilds: true,
+    ignoreDuringBuilds: false,
   },
   // Include OpenAPI files in output tracing for Vercel deployments
   outputFileTracingIncludes: {