Overview
JavaScript leads Libraries's secondary barrier stack above the norm
| Value | |
|---|---|
| WAF | 92% |
| Antibot | 16% |
| CAPTCHA | 9% |
| JavaScript | 36% |
| Rate Limiting | 16% |
| TLS | 11% |
WAF at 92% is the dominant barrier. JavaScript (36%) leads secondary coverage. The remaining barriers sit materially lower, giving Libraries a narrow but defined secondary layer.
Barrier Landscape
WAF leads Libraries at 92% — JavaScript is the main secondary layer
| Value | |
|---|---|
| WAF | 92% |
| Antibot | 16% |
| CAPTCHA | 9% |
| JavaScript | 36% |
| Rate Limiting | 16% |
| TLS | 11% |
| Has robots.txt | 69% |
| Blocks AI crawlers | 8% |
WAF dominates at 92%. JavaScript (36%) leads active secondary barriers, followed by Rate Limiting (16%). The remaining three barriers all sit at or below 16% — a concentrated rather than broadly stacked profile.
Libraries's barrier counts are spread — no single configuration dominates
| % of sites | |
|---|---|
| 0 barriers | 8% |
| 1 barrier | 40% |
| 2 barriers | 34% |
| 3 barriers | 5% |
| 4 barriers | 8% |
| 5 barriers | 5% |
| 6 barriers | 0% |
Barrier counts vary widely across Libraries sites. Single-barrier configurations are the modal count at 40%, but the distribution is broad. 18% of sites carry three or more.
Libraries sites are predominantly Simple to access
| Mean recommended tier | |
|---|---|
| All sites | 1.25 |
A mean recommended tier of 1.25 and a median of Simple place Libraries among the most accessible sectors surveyed. 80% of sites are Simple to access; 5% require Moderate or above.
Simple tier covers more than three-quarters of Libraries sites
| % of sites | |
|---|---|
| 1 - Simple | 79.6% |
| 2 - Easy | 15.3% |
| 3 - Moderate | 5.1% |
| 4 - Complex | 0% |
| 5 - Advanced | 0% |
Simple (80%) is the most common tier. Simple and Easy together account for 95% of sites, while 5% land at Moderate and 0% at Complex or Advanced.
robots.txt
Around seven in ten Libraries sites publish a robots.txt
| % of sites | |
|---|---|
| Publish a valid robots.txt | 69% |
69% of Libraries sites have a valid robots.txt. The remaining 31% leave crawl policy entirely undefined — a meaningful gap for a sector of this scale.
Most Libraries sites name one bot or none in their robots.txt
| % of sites | |
|---|---|
| 0 | 37% |
| 1 | 37% |
| 2–4 | 8% |
| 5–9 | 8% |
| 10–15 | 6% |
| 16+ | 4% |
37% of Libraries sites name zero agents and 37% name one. A mean of 3.8 is pulled up by a small number of sites with extensive policies, while the median stays at 1.
SEO audit tools lead Libraries's robots.txt mentions ahead of AI crawlers
| % of sites | |
|---|---|
| AI crawlers | 8% |
| SEO / search indexing | 10% |
| SEO audit tools | 17% |
| Commercial scrapers | 4% |
| Social / content scrapers | 5% |
| Archive / research crawlers | 2% |
| Monitoring / uptime bots | 0% |
SEO audit tools are mentioned by 17% of Libraries sites — the leading bot category, ahead of AI crawlers at 8%. Figures are percentages of all 100 sites surveyed.
A blanket Disallow: / posture appears in 8% of Libraries sites
| % of sites | |
|---|---|
| Uniform per-agent rules | 35% |
| Path-level mixed rules | 24% |
| Allow-only (no Disallow rules) | 2% |
| Mixed AI posture | 2% |
| Blanket Disallow: / | 8% |
Of Libraries sites with robots.txt, 8% issue a blanket Disallow: /. Uniform per-agent rules remains the dominant posture at 35%. All figures are percentages of all 100 sites surveyed.
SemrushBot leads named Disallow rules in Libraries robots.txt
| Disallowed | Allowed (whitelisted) | |
|---|---|---|
| * | 59% | 28% |
| SemrushBot | 11% | 1% |
| AhrefsBot | 10% | — |
| MJ12bot | 10% | — |
| Googlebot | 6% | 3% |
| GPTBot | 8% | 1% |
| OAI-SearchBot | 6% | 2% |
| ClaudeBot | 5% | 2% |
| SemrushBot-SA | 7% | — |
| Bingbot | 4% | 2% |
| Amazonbot | 5% | 1% |
| CCBot | 5% | 1% |
| Google-Extended | 4% | 2% |
| Twitterbot | 4% | 2% |
| YandexBot | 4% | 2% |
| Bytespider | 6% | — |
| dotbot | 6% | — |
| Alexibot | 5% | — |
| SurveyBot | 5% | — |
| Xenu’s | 5% | — |
| Xenu’s Link Sleuth 1.1c | 5% | — |
| rogerbot | 5% | — |
| Baiduspider | 3% | 2% |
| ChatGPT-User | 4% | 1% |
| Claude-SearchBot | 3% | 2% |
Values are percentages of all 100 Libraries sites surveyed. The wildcard (*) leads at 59% Disallow. Among named agents, SemrushBot, AhrefsBot, MJ12bot are the most frequently targeted — focused on non-AI crawlers.
Industry Cohort
Libraries sits mid-table within the Education cohort
| WAF | Antibot | CAPTCHA | JavaScript | Rate Limit | TLS | robots.txt | Blocks AI | Tier | |
|---|---|---|---|---|---|---|---|---|---|
| Distance Learning | 97% | 27% | 37% | 43% | 26% | 16% | 85% | 25% | Tier 2 |
| Education | 98% | 17% | 18% | 37% | 18% | 10% | 81% | 15% | Tier 2 |
| Foreign Language | 96% | 15% | 20% | 42% | 14% | 13% | 82% | 6% | Tier 1 |
| Libraries | 92% | 16% | 9% | 36% | 16% | 11% | 69% | 8% | Tier 1 |
| Reference | 81% | 15% | 17% | 31% | 16% | 3% | 60% | 17% | Tier 1 |
| Science | 90% | 15% | 11% | 35% | 15% | 9% | 79% | 10% | Tier 2 |
| Training & Certification | 93% | 15% | 19% | 41% | 17% | 11% | 75% | 7% | Tier 1 |
Across Education, Libraries's barrier rates are broadly in line with peers. WAF at 92%, JavaScript at 36%, and AI blocking at 8% all sit near the cohort median. Tier difficulty (mean 1.26) is below the group average.