Fern

buildwithfern.com/learn
Score: 98 out of 100, grade A98
Grade A
Last checked: April 28, 2026 · Rerun
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Simulation: Fern // bud
Day 0
CategoryDevTools
Checks passed21/23Warnings0Failed1

Fern scores 98/100 (Grade A), placing it among the most AI-agent-ready documentation sites evaluated. It passes 21 of 23 checks (91%), demonstrating strong support for AI coding agents. 1 item require attention to reach a perfect score.

# Agent Score Fix Report — Fern
URL: https://buildwithfern.com/learn
Score: 98/100 (Grade A)

I need help improving the AI-readiness of the documentation at https://buildwithfern.com/learn.
Agent Score found 1 failing checks and 0 warnings.

## Failing Checks (1)
- [observability] Markdown Content Parity: 6 of 10 pages have substantive content differences between markdown and HTML (avg 19% missing)



## Fix Instructions

For each issue above, please:
1. Analyze the documentation site at https://buildwithfern.com/learn
2. Implement the specific fix
3. Verify the fix would cause the check to pass

### Common fixes:
- **No llms.txt**: Create /llms.txt following https://llmstxt.org — list all doc pages in markdown format
- **No .md URL support**: Configure your docs platform to serve pages at equivalent .md URLs (e.g. /docs/quickstart.md)
- **No content negotiation**: Return markdown when request includes Accept: text/markdown header
- **Large page size**: Reduce nav boilerplate, inline scripts, and repetitive markup
- **No sitemap**: Generate /sitemap.xml listing all documentation URLs
- **Auth walls**: Ensure docs pages return 200 without requiring login cookies or tokens
- **No Last-Modified header**: Configure your server/CDN to include Last-Modified response headers
- **Tab content hidden**: Ensure tabbed content is rendered in the HTML (not JS-only) so agents can read all variants

## Run afdocs Locally for More Detail

To get deeper visibility into what's failing, run afdocs against your docs:

  npx afdocs check https://buildwithfern.com/learn --fixes --verbose

- **--fixes**: Adds "Fix:" lines to the output for each warn/fail check with actionable remediation steps
- **-v, --verbose**: Shows per-page details (specific URLs, character counts, error codes) for checks with issues — useful for per-URL visibility into what's failing
CHECK RESULTS

How your docs scored

auth-gate-detectionAll 10 sampled pages are publicly accessibleLearn more
auth-alternative-accessAll docs pages are publicly accessible; no alternative access paths neededLearn more
markdown-content-parity6 of 10 pages have substantive content differences between markdown and HTML (avg 19% missing)Learn more
llms-txt-coveragellms.txt covers 96% of 361 sitemap doc pagesLearn more
cache-header-hygieneAll 12 endpoints have appropriate cache headersLearn more
llms-txt-existsllms.txt found at 2 locations; using https://buildwithfern.com/learn/llms.txt as canonicalLearn more
llms-txt-validllms.txt follows the proposed structure (H1, blockquote, heading-delimited link sections)Learn more
llms-txt-sizellms.txt is 1,343 characters (under 50,000 threshold)Learn more
llms-txt-links-resolveAll 6 same-origin links resolve (6 total links)Learn more
llms-txt-links-markdown6/6 same-origin links point to markdown content (100%)Learn more
llms-txt-directive-htmlllms.txt directive found in HTML of all 10 sampled pages, near the top of contentLearn more
llms-txt-directive-mdllms.txt directive found in markdown of all 10 sampled pages, near the top of contentLearn more
markdown-url-support10/10 sampled pages support .md URLs (100%)Learn more
content-negotiation10/10 sampled pages support content negotiation (100%)Learn more
rendering-strategyAll 10 sampled pages contain server-rendered contentLearn more
page-size-markdownAll 10 pages under 50K chars (median 7K, max 11K)Learn more
page-size-htmlAll 10 sampled pages under 50K chars (median 797K HTML → 13K markdown (98% boilerplate))Learn more
content-start-positionContent starts within first 10% on all 10 sampled pages (median 0%)Learn more
tabbed-content-serializationNo tabbed content detected across 10 sampled pagesLearn more
section-header-qualityNo tabbed content found; header quality check not applicableLearn more
markdown-code-fence-validityAll 37 code fences properly closed across 12 pagesLearn more
http-status-codesAll 9 sampled pages return proper error codes for bad URLs; 1 failed to fetchLearn more
redirect-behaviorNo redirects detected across 10 sampled pagesLearn more

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