Update MCP server documentation to describe auto-generated functionality

[devin-ai-integration]

Update MCP server documentation to describe auto-generated functionality

Summary

Updated the MCP server documentation to describe Fern's auto-generated MCP server functionality instead of linking to the external fern-api/fern-mcp-server repository. The changes include:

1. Revised /docs/ai/mcp-server page: Rewrote the content to explain that Fern automatically generates and hosts an MCP server for every documentation site, describing how it works, how to access it, and its features
2. Updated getting-started overview card: Changed the card from linking to the GitHub repository to linking to the internal MCP server documentation page
3. Corrected MCP server URL: Updated from /mcp to /_mcp/server based on the middleware implementation in fern-platform

The documentation now explains that the MCP server:

• Is automatically generated and hosted for every docs site
• Provides a searchDocs tool powered by Ask Fern AI
• Is available at your-documentation-site.com/_mcp/server
• Supports authentication and requires no configuration

Review & Testing Checklist for Human

⚠️ High Priority - Please Verify:

• Test the MCP server URL: Visit /_mcp/server on a live Fern docs site to confirm this is the correct public-facing URL (I found this in the middleware code but couldn't test it)
• Verify link path: Check that the internal link /docs/ai/mcp-server resolves correctly when the documentation is published
• Test MCP functionality: If possible, connect an AI client (Claude Desktop, Cursor, etc.) to a docs site's MCP server to verify the documentation accurately describes the behavior
• Check for other references: Search the codebase for any remaining references to fern-api/fern-mcp-server that should be removed or updated
• Review content accuracy: Verify that the description of how the MCP server works matches the actual implementation (I based this on reading the fern-platform code but couldn't test it)

Notes

• I couldn't access the Slack thread mentioned in the request, so there may be additional context or requirements I missed
• Vale linting couldn't be run locally (command not found), but I followed the documentation style guidelines
• The URL was corrected from /mcp to /_mcp/server based on the middleware.ts implementation at line 175-178

Link to Devin run: https://app.devin.ai/sessions/ff3bcad83fc9458989fac948b0838de8
Requested by: [email protected] (@dannysheridan)

[devin-ai-integration]

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[github-actions]

📝 [vale] _{reported by reviewdog 🐶}
[FernStyles.Headings] 'Accessing your MCP server' should use sentence-style capitalization.

[github-actions]

🚫 [vale] _{reported by reviewdog 🐶}
[Microsoft.Auto] In general, don't hyphenate 'auto-generated'.

[github-actions]

⚠️ [vale] _{reported by reviewdog 🐶}
[FernStyles.Current] Avoid time-relative terms like 'latest' that become outdated

[github-actions]

🌿 Preview your docs: https://fern-preview-9bdaa9ab-5947-45da-9354-5cb091d0a282.docs.buildwithfern.com/learn

[github-actions]

📝 [vale] _{reported by reviewdog 🐶}
[FernStyles.Headings] 'Access your MCP server' should use sentence-style capitalization.

[github-actions]

🌿 Preview your docs: https://fern-preview-4e655c0a-2371-4922-9df0-d7f6583fe493.docs.buildwithfern.com/learn

[github-actions]

🌿 Preview your docs: https://fern-preview-faca3e60-23fa-4a28-9963-e46d740f04d5.docs.buildwithfern.com/learn

[github-actions]

🌿 Preview your docs: https://fern-preview-ec9ba5f1-05a6-440e-b750-e7c5c437f170.docs.buildwithfern.com/learn