Static pre-check · Fri, 07 Aug 2026 06:50:08 GMT
jsfiddle.net
AI agents struggle to discover and crawl JSFiddle due to missing robots.txt, sitemap, and llms.txt files preventing proper site indexing.
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Discovery 10/22.2
Documentation linked from the homepagedetailsFAIL
no link to documentation found in the homepage HTML
Fix: Link your docs from the homepage with visible anchor text ("Docs", "Documentation", "Developers"). An agent that cannot find your docs from your homepage will guess your API.
robots.txt allows agent crawlersdetailsFAIL
robots.txt blocks ClaudeBot, GPTBot, Google-Extended from /
Fix: Remove the Disallow rules for ClaudeBot, GPTBot, Google-Extended in /robots.txt, or narrow them to the paths you really want kept out. Blocking these crawlers is the single most effective way to make your product invisible to AI agents.
sitemap.xml exists and parsesdetailsFAIL
sitemap.xml not served (HTTP 404)
Fix: Publish /sitemap.xml listing your public pages, and reference it from robots.txt with a `Sitemap:` line.
Canonical URL declareddetailsWARN
no <link rel="canonical">
Fix: Add <link rel="canonical"> to the homepage so agents and crawlers converge on one URL for this page.
Open Graph tags presentdetailsWARN
no Open Graph tags
Fix: Add og:title and og:description meta tags.
robots.txt points at the sitemapdetailsWARN
robots.txt does not reference a sitemap
Fix: Add `Sitemap: https://<domain>/sitemap.xml` to /robots.txt so crawlers find it without guessing.
API reference linked from the homepagedetailsPASS
1 API link(s), e.g. https://console.mistral.ai/api-keys
Homepage has a meta descriptiondetailsPASS
81 characters
Homepage has a descriptive titledetailsPASS
'JSFiddle - React, Tailwind, and code Playground' (47 chars)
robots.txt existsdetailsPASS
HTTP 200, 1934 bytes
Brand findable in agent searchdetailsN/A
search-based checks are deferred — excluded from the score
Listed in an MCP registrydetailsN/A
registry lookup not implemented in v1 — excluded from the score rather than guessed
Accessibility 26.3/33.3
llms.txt is publisheddetailsFAIL
/llms.txt not served (HTTP 404)
Fix: Publish /llms.txt: a plain-markdown index that tells an agent what this product is and where the authoritative docs live. It is the cheapest high-leverage file you can add.
Structured data (JSON-LD) on the homepagedetailsWARN
no JSON-LD blocks on the homepage
Fix: Add a JSON-LD block (schema.org Organization or SoftwareApplication) so agents get your name, description and links as data rather than prose.
llms-full.txt is publisheddetailsWARN
/llms-full.txt not served
Fix: Optional but cheap: publish /llms-full.txt with your docs inlined as one markdown file, so an agent can read everything in a single fetch.
Serves markdown when asked for itdetailsWARN
Accept: text/markdown → text/html; charset=utf-8
Fix: Optional but increasingly expected: honour `Accept: text/markdown` by serving a markdown rendering of the page, so agents skip HTML parsing entirely.
Homepage responds to an agent requestdetailsPASS
HTTP 200 for / (agent UA)
Served over HTTPSdetailsPASS
https://jsfiddle.net/
Same response for agents and browsersdetailsPASS
both User-Agents got HTTP 200
Homepage has readable text without JavaScriptdetailsPASS
8661 characters of text in the served HTML
Content-to-markup ratio is reasonabledetailsPASS
ratio 0.0674 (8661 chars of 128454)
No long redirect chain on the homepagedetailsPASS
0 redirect(s)
Docs are readable without JavaScriptdetailsN/A
/docs not served (HTTP 404) — docs may live on another path or host
Links in llms.txt resolvedetailsN/A
no llms.txt
llms.txt is structured markdowndetailsN/A
no llms.txt to parse
Usability 22.2/44.4
agents.md is publisheddetailsWARN
/agents.md not served (HTTP 404)
Fix: Publish /agents.md: what an agent may do here, which endpoints matter, auth requirements, and rate limits. It is the agent-facing counterpart to a README.
A documentation endpoint respondsdetailsWARN
/docs → HTTP 404
Fix: Serve docs at the conventional /docs path, or redirect it to wherever they live. Agents try conventional paths first.
Errors are machine-readabledetailsWARN
404 returns HTML, not a machine-readable body
Fix: Content-negotiate your errors: return a JSON body with a stable `code` (and a `next_action` where recovery exists) to clients that ask for JSON.
OpenAPI document publisheddetailsWARN
/openapi.json not served (HTTP 404)
Fix: If you have an HTTP API, publish its OpenAPI document at a predictable path (/openapi.json). It is the difference between an agent reading your contract and an agent guessing it. If you have no HTTP API, ignore this.
.well-known/mcp.json advertises an MCP serverdetailsWARN
/.well-known/mcp.json not served (HTTP 404)
Fix: If you run an MCP server, advertise it at /.well-known/mcp.json so agents discover it without being told its URL.
The /api root behaves predictablydetailsN/A
/api → HTTP 404 (no API at the conventional root)
MCP server completes the initialize handshakedetailsN/A
no MCP endpoint found to probe (none in the input URL and none advertised at /.well-known/mcp.json)
MCP tool parameters are typed and describeddetailsN/A
no listed MCP tools to inspect
Every MCP tool has a descriptiondetailsN/A
no listed MCP tools to inspect
MCP server lists toolsdetailsN/A
no MCP endpoint to probe
OpenAPI declares its auth schemedetailsN/A
no parseable OpenAPI document
OpenAPI operations are describeddetailsN/A
no parseable OpenAPI document
OpenAPI documents error responsesdetailsN/A
no parseable OpenAPI document
OpenAPI document is structurally validdetailsN/A
no parseable OpenAPI document
Payments not applicable — excluded from the score
Serves a 402 payment challengedetailsN/A
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.
Declares AP2 / ACP supportdetailsN/A
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.
Publishes x402 payment metadatadetailsN/A
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.
Badge
Shows the current scan score and grade for this domain, straight from the latest static pre-check.
[](/score/jsfiddle.net)<a href="/score/jsfiddle.net"><img src="/api/badge/jsfiddle.net" alt="agent readiness score" /></a>