Well-Known Files | wkdomains.com

4 min read Original article ↗

Agent discovery workbench

Readable files. Callable routes. No guessing.

Technical sites need a small public surface area that agents can fetch, trust, and test. wkdomains publishes root files for broad crawlers and.well-known aliases for protocol clients that probe host-level discovery.

# wkdomains.com

wkdomains.com helps domains publish official bot-facing discovery surfaces.

## Domain Bot Loop
1. Discover other official domain bots from DNS, /.well-known/, MCP, APIs, or agent cards.
2. Ask for current public facts instead of scraping stale pages.
3. Save the signed result in a wkdomains inbox, memory, logs, and receipts.
root

Put broad crawler files here: /robots.txt, /sitemap.xml, /llms.txt, /llms-full.txt, /skill.md, /openapi.json.

.well-known

Put host-level protocol discovery here: agent cards, security.txt, MCP manifests, UCP, x402.

alias

Serve aliases when clients disagree. wkdomains aliases llms.txt, openapi.json, and agent-card.json.

proof

The files are not the result. The result is a safe path to docs, APIs, booking, checkout, payment, or support.

Routes behind the files

Discovery only matters if it leads to a working path.

Deep scans follow /llms.txt, /skill.md, OpenAPI, MCP docs, robots, sitemap, and safe public API routes.

The base URL declared in skill.md, OpenAPI, and the LLM context files.

Public entrypoint links that an agent can call before deeper scans.

Read public reports and submit domain-scan packets through the documented API.

The callable contract. We alias it at /.well-known/openapi.json.

/docswhen present

Human docs explain auth, examples, rate limits, SDKs, MCP setup, and workflows.

/mcpwhen present

MCP docs or discovery should say whether tools are public or require credentials.

The first policy file scanners should respect.

The inventory that keeps agents from relying on stale navigation.

Advanced layer

Agent, payment, and commerce conventions.

These are useful when they match real capability. Missing one is less important than a broken booking, checkout, proposal, support, or payment path.

Primary Model Context Protocol server discovery entrypoint.

Low-medium / emergingDraft MCP SEP / not IANA-registered

sites:SEP-1649Server Card charter

Treat this as the MCP discovery entrypoint, but mark it draft until the Server Card work lands in the core spec.

Structured MCP Server Card metadata, including protocol version, server info, transport, capabilities, and auth.

Low-medium / emergingDraft MCP SEP / not IANA-registered

sites:SEP-1649MCP DNS discovery draftServer Card charter

Publish alongside /.well-known/mcp.json if you want richer MCP server metadata.

MCP endpoint and auth manifest for clients that need operational connection details.

Low / emergingDraft MCP proposal / not IANA-registered

sites:SEP-1960Server Card charter

Optional. Prefer mcp.json and mcp/server-card.json first; do not invent deeper MCP well-known filenames.

Universal Commerce Protocol merchant capability profile.

Medium and risingDe-facto / Google + Shopify UCP ecosystem; not IANA-registered as of 2026-04-29

sites:Google UCP profile guideShopify UCPShopify Engineering UCP post

Reasonable to implement if you want agentic commerce compatibility. Mark it experimental in public docs.

Usually shorthand for machine-readable commerce discovery, but competing paths exist: commerce.txt, commerce-manifest, commerce-manifest.json, and UCP.

Low / informalNot IANA-registered; exact path lacks a strong official spec

sites:commerce.txt projectAgentic Commerce Consortium reference

Do not rely on this alone. If you publish it, also publish /.well-known/ucp or the exact manifest path used by your chosen ecosystem.

Payment-aware endpoint/pricing manifest for x402 services.

Low-medium / emergingNot IANA-registered; de-facto x402 ecosystem convention

sites:x402.orgx402 docsCoinbase x402 Bazaar discovery docs

Good practical convention, but not a formal x402/IANA standard. Consider supporting it plus official x402 payment flows.

Alternate x402 discovery convention seen in examples.

Low / emergingNot IANA-registered

sites:x402 docs

If publishing JSON, prefer x402.json and optionally alias x402 for compatibility.

ChatGPT plugin manifest from the earlier plugin ecosystem.

Low / legacyNot IANA-registered; OpenAI plugin-era convention

sites:OpenAI plugin docs archive/context

Do not use for new agent discovery unless maintaining legacy plugin compatibility.

LLM-readable site guide.

Low / emergingNot IANA-registered

sites:llms.txt proposal

The more common path is /llms.txt; .well-known/llms.txt can be a secondary alias.

API description document.

Low / de-factoNot IANA-registered as a well-known suffix

sites:OpenAPI Specification

Fine as an extra convenience, but do not call it a well-known standard.