Tools / llms.txt
llms.txt validator
Paste, upload, or fetch any llms.txt file and get a per-line report. Checks conformance against the llmstxt.org reference spec, flags malformed Markdown link syntax, missing required headings, and optionally verifies that every referenced URL is reachable.
What we check
- structure · `# Title` presence, position, uniqueness; `## Section` headings; H3+ flagged
- link syntax · valid Markdown link format, empty text/url, relative paths, fragments, http→https
- duplicates · same URL across sections, same link text
- reachability (opt-in) · HEAD requests with GET fallback, per-link timeout, slow-link threshold
- style · trailing whitespace, tab characters, empty sections
Use it from your CLI
# one-shot
npx @bridgetoagent-com/llms-txt-validator ./llms.txt
# with reachability check
npx @bridgetoagent-com/llms-txt-validator \
https://example.com/llms.txt --check-links
# machine-readable for CI
npx @bridgetoagent-com/llms-txt-validator \
./llms.txt --json > report.jsonExit codes: 0 pass, 1 warnings, 2 errors.
Want one generated from your real site?
This validator checks any `llms.txt` you already have. The BridgeToAgent kit is the next step: $49, generates a validated `llms.txt` plus the other two agent-readable files (`agents.json`, `agent-instructions.md`) from your real DOM in under two minutes. Every file passes this validator before it ships.