Use in your browser
Check a domain's live ads.txt and app-ads.txt against the IAB spec and confirm the seller IDs it declares appear in the sellers.json of up to 10 ad systems, or compare two domains line by line.
Guest includes 50 lifetime app requests. Create a free account for 100 app requests each calendar month. One allowance across every app, in your browser and your agent.One allowance across every app, in your browser and your agent. Manage usage
Guest access is available after setup. Full account linking verified by PowMCP: Claude only.
Connect this app on its own. Add other PowMCP apps whenever your agent needs another job done.
Open the apps workspace
Choose your agent. Each button opens a new tab with only this app's endpoint ready to add.
ClaudeOpen Claude setup Guest access + account linking verified by PowMCP
VS CodeOpen VS Code setup Guest access available · Account linking not yet verified
KiroOpen Kiro setup Guest access available · Account linking not yet verified
LM StudioOpen LM Studio setup Guest access available · Account linking not yet verified
Visual StudioOpen Visual Studio setup (Windows) Guest access available · Account linking not yet verifiedCopy one ready-to-send prompt for any agent that supports remote MCP connections.
For clients that require manual configuration, use this app-only endpoint, its JSON entry, or one terminal command.
ChatGPT: enable Developer mode in Settings → Security and login, then add this MCP endpoint from the Plugins page. Availability depends on your account and workspace policy. PowMCP has not yet verified ChatGPT account linking. OpenAI setup guide
https://powmcp.com/ads-txt-check/mcp {
"mcpServers": {
"powmcp-ads-txt-check": {
"type": "http",
"url": "https://powmcp.com/ads-txt-check/mcp"
}
}
}Terminal agents add this app with one command:
claude mcp add --transport http powmcp-ads-txt-check https://powmcp.com/ads-txt-check/mcpcodex mcp add powmcp-ads-txt-check --url https://powmcp.com/ads-txt-check/mcpgemini mcp add --transport http powmcp-ads-txt-check https://powmcp.com/ads-txt-check/mcpManage, disable, or remove this connection in your agent's own MCP settings. PowMCP does not label an external connection as installed without confirmation from that client.
Proof
Validate ads.txt and cross-check sellers.json in chat
Preflight a publisher's public ads.txt and app-ads.txt from chat with live IAB-spec line validation and a bounded sellers.json reciprocal cross-reference, or compare the authorized-seller sets of two domains under identical limits.
Request cost1 completed result
Guests get 50 lifetime app requests. Free accounts get 100 each calendar month.
adstxt_check
Preflight one public publisher domain's live ads.txt and app-ads.txt against the IAB ads.txt spec, then cross-reference the declared seller IDs against the hosted sellers.json files of the declared ad systems the crawl reaches: up to 10 distinct hosts per run, with the crawled and uncrawled counts reported in every result. Derives the /ads.txt and /app-ads.txt URLs for the supplied host, SSRF-guarded and byte-bounded, parses DIRECT/RESELLER rows and variable declarations, and reports per-file reachability, content-type, parsed record count, issue counts by severity, malformed/duplicate-row findings, and a distinguished file state (ads-txt-not-published vs ads-txt-invalid). For each declared ad system inside that bound it fetches that system's sellers.json (bounded crawl, default and maximum 10 distinct hosts) and reports seller-id-matched, seller-id-mismatch, or sellers-json-unreachable per host, plus how many of the declared ad systems were not crawled at all. It validates published-file conformance and reciprocity only against a dated IAB spec profile. It does not certify seller legitimacy, detect fraud, guarantee ad revenue, access ad accounts, or audit site SEO/performance. Each call fetches live files across several hosts and can take up to 110 seconds.
adstxt_compare
Compare the authorized-seller setups of exactly two public publisher domains under identical bounded limits: production versus staging, before versus after a partner change, or one property versus another. Runs the same IAB-spec ads.txt / app-ads.txt validation and bounded sellers.json reciprocity crawl (default up to 5 sellers.json hosts per domain) on each, then reports side-by-side pass status, the record-count delta, the added and removed authorized-seller lines within the parse cap, issue-count deltas, per-domain distinguished file states, reciprocity-result differences, the shared spec-profile date, and a winner only when the measured checks support one. Use adstxt_check for a single domain. It compares published-file conformance and reciprocity facts only. It does not certify seller legitimacy, detect fraud, or judge which setup is more profitable. Each comparison fetches live files across several hosts per domain and can take up to 110 seconds.
Other apps for the jobs next to Ads.txt Check.
Scope and boundaries for Ads.txt Check.
Check theguardian.com with sellers.json cross-referencing enabled for up to 10 declared ad-system hosts, or compare the authorized-seller lines on vox.com and eater.com.
Start with each file's state and pass: pass requires a valid published ads.txt and, if app-ads.txt is published, a valid one; sellers.json reciprocity does not affect pass. Fix file errors first, then investigate seller-ID mismatches. Reciprocity is inconclusive when crawling is disabled, incomplete, unreachable, or truncated.
The check validates published-file syntax and bounded sellers.json reciprocity against its dated IAB profile. It does not verify that a seller is legitimate, detect advertising fraud, access ad accounts, or predict revenue, and hosts beyond maxSellerHosts remain uncrawled.