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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

Superflow Free Tools

19 free website QA and AI-visibility tools. Remote HTTP MCP, no account, no API key.

Checks passed
12 / 22

2 failed · 8 not measured

Median response
536 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
16

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 536 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name superflow-free-tools.

  • Pass
    Lists tools

    tools/list returned 16 tools.

  • Pass
    Current protocol

    Negotiated 2025-06-18. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 536 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 536 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    52 of 52 parameters have a description (100%). The bar is 80%.

  • Fail
    Safety hints

    16 tools set neither readOnlyHint nor destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-08-21T00:37:41.816345Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Superflow Free Tools

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http superflow-free-tools https://usesuperflow.ai/api/mcp

Capabilities

Tools 16

build_utm_url

Build a campaign URL with utm parameters, normalised to one tagging convention, and report which GA4 default channel group the link will land in. Warns about the mistakes that silently break reporting: an unrecognised medium that drops traffic into Unassigned, casing that splits one source into several report rows, PII in a campaign name. Pure string work: nothing is fetched and nothing is stored. Returns { url, normalized, channel, issues[] with level, field and message }. Limit: None. The work is local and costs nothing.. Allow up to 10s for a response. Free, no account, no API key.

Discovered
capture_full_page_screenshot

Capture a full-height PNG of a page in a real headless browser, scrolling first so lazy-loaded content renders. Returns a signed link to the image that expires in about 24 hours; download the bytes if you need to keep them. No watermark and no height cap. Cannot capture anything behind a login. Returns { imageUrl, expiresAt, bytes, width, height, deviceType }. Limit: 10 runs per hour per IP. Allow up to 90s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
check_ai_visibility

Check whether AI assistants (ChatGPT, Claude, Perplexity, Google AI) can reach, read, and cite a web page. Runs the full suite: robots.txt rules per AI crawler, a live firewall test that requests the page as GPTBot, JavaScript dependency, llms.txt, headings, structured data, and author identity. Returns a score out of 100 with a grade, a score per category, and a finding per check with why it matters and how to fix it. Use this for a whole-page verdict; use check_robots_txt_for_ai when the question is only about crawler access. Returns { ok, report: { score, grade, scoredOutOf, categories[], findings[] with why and fix, detection }, cached, ageSeconds }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
check_favicon

Check whether a site's favicon actually works. Reads every icon declaration in the page head, then fetches each one, the web app manifest, and the implicit /favicon.ico, and identifies the real format and pixel dimensions from each file's header bytes. Catches the failures a status-code check misses: a catch-all route answering an icon path with HTML at HTTP 200, a sizes attribute that disagrees with the file, an icon served over http on an https page. Use this when a favicon is missing or blurry; use check_social_preview for the image that appears when a link is shared. Returns { hasWorkingFavicon, tabIcon, icons[] with format, dimensions, bytes and problem, manifest, themeColor, checks[] with id, status and fix, counts }. Limit: 60 runs per hour per IP. Allow up to 30s for a response. Free, no account, no API key.

Discovered
check_og_video

Check whether a page's og:video plays when its link is shared. Reads every og:video declaration and its structured properties (secure_url, type, width, height) the way ogp.me defines them, then fetches the first 512 KB of the video and identifies the real format from the file header, along with byte-range support, MP4 fast start, pixel size and length. Also fetches og:image as the poster and reports the tags the other readers use instead: the X player card (twitter:card player, twitter:player) and a Google VideoObject in JSON-LD. Pass the page URL, not the video file. Use check_social_preview for how the title, description and image render per platform. Returns { hasPlayableVideo, primary, videos[] with declared tags and probe (format, kind, dimensions, durationSeconds, rangeSupported, fastStart, problem), image, ogType, videoMeta, twitter, videoObject, checks[] with id, status and fix, counts }. Limit: 60 runs per hour per IP. Allow up to 30s for a response. Free, no account, no API key.

Discovered
check_robots_txt_for_ai

Test a site's robots.txt against every AI crawler that matters (GPTBot, ClaudeBot, PerplexityBot, Google-Extended, CCBot, Googlebot, Bingbot and the rest) and report which are allowed, which are blocked, and which rule decided it. Also runs a firewall test, because CDN-level blocks stop crawlers before robots.txt is ever read. This is the access-scoped view of check_ai_visibility. Returns { ok, report: { accessScore, crawlers[] with the rule that decided each verdict, firewall, findings[] }, cached, ageSeconds }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
check_social_preview

Read a page's Open Graph and Twitter card tags and report how the link will render on X, LinkedIn, Facebook, Slack, Discord, and Google. Returns a per-platform preview (title, description, image) plus the findings for tags that are missing, truncated, or the wrong size. Returns { ok, report: { previews[] per platform, tags, summary, findings[] }, cached, ageSeconds }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
check_website_status

Check whether a website is up right now. Makes one live GET request to the URL from Superflow's servers, following redirects, and reports a verdict: up when the server answers with any HTTP status below 500, down on a 5xx, a timeout after 10 seconds, a refused connection, or an unresolvable domain. Returns the HTTP status, the response time, the final URL after redirects, and the time of the check. Never cached, so every call is a fresh request. Use this to answer 'is it down or is it just me'; use check_favicon or check_social_preview to inspect what a page contains. Returns { verdict: 'up' | 'down', reason?, httpStatus?, responseTimeMs, requestedUrl, finalUrl, redirectCount, checkedAt, submittedUrl }. Limit: 60 runs per hour per IP. Allow up to 30s for a response. Free, no account, no API key.

Discovered
detect_tech_stack

Identify the platform, framework, CMS, ecommerce apps, analytics, CDN, and hosting behind a site by fingerprinting one page's HTML and response headers. One fetch, no rendering and no crawl, so it answers in about a second. A site behind bot protection is reported as blocked rather than as empty. Returns { platformName, theme, apps[], fonts[], analytics[], hosting[], renderMode, url, status, fetchedAt }. Limit: 60 runs per hour per IP. Allow up to 30s for a response. Free, no account, no API key.

Discovered
find_meeting_times

Find overlapping working hours and meeting times across cities or countries. Resolves locations to IANA time zones and applies daylight saving for the requested date. Returns resolved locations, overlap windows, the earliest matching meeting starts with UTC and local times, readable copy text, and a link to open the plan. Ambiguous names or countries with multiple zones return choices: retry with a returned location ID or a more specific city/region/country. The same working schedule is applied in each location's local time; the browser plan supports individual schedules. Does not access calendars, account for holidays, send invitations, or book meetings. Returns { ok, date, dateZone, durationMinutes, locations[], overlapMinutes, overlapWindows[], slots[] with UTC/local times and copyText, totalAvailableStarts, hasMore, planUrl, availability }. Limit: No application rate limit. Up to 8 locations, 20 returned starts, and a 16 KB request body; no result storage.. Allow up to 10s for a response. Free, no account, no API key.

Discovered
generate_alt_text

Find every image on a page and draft alt text for the ones that need it, using a vision model that actually looks at the image. Lists every image with the alt it has today, the suggested alt, whether it looks decorative, and why any image was skipped. Up to 10 images per run go to the model. The suggestions are drafts for a human to review. Returns { images[] with src, hadAlt, currentAlt, suggestedAlt, isDecorative, skippedReason; counts; model }. Limit: 10 runs per hour per IP. Allow up to 90s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
generate_json_ld

Read a page and write a schema.org JSON-LD block for it, then validate that block against the same checks a validator would run. The markup is model-written from the page's own content and should be reviewed before it is published. Returns the block ready to paste into a <script type="application/ld+json"> tag. Returns { ok, report: { detectedType, jsonLd, jsonLdString, validation: { findings[], passed }, model } }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
generate_llms_txt

Generate llms.txt and llms-full.txt for a site, following the llmstxt.org convention. Inventories the site from its robots.txt, sitemaps, and homepage links, then writes an index file and a full file with page content inlined. Deterministic: no model is involved, so two runs over an unchanged site produce the same bytes. Returns the file contents ready to write to disk. Returns { ok, report: { siteName, llmsTxt, llmsFullTxt, pagesDiscovered, pagesIncluded, truncated }, cached, ageSeconds }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
hash_md5

Hash text to an MD5 hex digest. Useful for checksums, cache keys, dedupe keys, and Gravatar-style identifiers. MD5 is broken for anything security-related: never use it for passwords or to verify authenticity. Returns { md5, algorithm, bytes }. Limit: None. The work is local and costs nothing.. Allow up to 10s for a response. Free, no account, no API key.

Discovered
page_to_markdown

Fetch one web page and convert it to clean CommonMark, with the navigation, cookie banners, and boilerplate stripped out. Use this to read a page as text an agent can reason over, or to publish a .md copy of a page alongside the HTML. Returns { ok, report: { markdown, title, description, wordCount, bytes, truncated, httpStatus }, cached, ageSeconds }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered
validate_json_ld

Read the structured data already on a page and check it against Schema.org and what search engines actually accept. Reports every JSON-LD block found, the type of each, and the errors and warnings per block. Returns { ok, report: { blockCount, invalidBlockCount, declaredTypes[], eligibility[], categories[], findings[] } }. Limit: 10 runs per hour per IP. Allow up to 75s for a response. Free, no account, no API key. Pass `url` to start a run. A slow run answers with `{ status: "pending", runId }` instead of a result: call this same tool again with just that `runId` to collect it, as many times as it takes. Collecting costs no rate-limit slot.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected536 ms16