# username.md > Own your handle and route identity for the Agentic Web. Buy a permanent > handle at username.md ($9 one-time); route humans and agents to your surfaces > on your terms. The edgier sister of about-me.md — who are /u/? ## What this site is - Purpose: handle-as-a-service — own a permanent, portable handle and use it as the routing root for your identity surfaces. - Owner: The Holding Company (https://holdingco.com/) - Status: live. $9 one-time buys a 5+ character handle outright (founding price, via Stripe). 4-character handles are premium ($99 one-time); 1-3 character handles go to a future auction. Pro is an optional subscription ($49/yr or $5/mo) for power features; Enterprise and API billing are separate. - Handle availability: https://username.md/api/availability/{handle} (returns whether a single handle is available; check per-handle, not in bulk). ## Product - [Home](https://username.md/): what it is, why handles matter, claim flow. - [Agent names](https://username.md/agents.html): name an AI agent — same registry and rights as human handles ($9 standard 5+ chars, $99 4-char premium). Every claimed name resolves at its own subdomain, mints a did:web DID, publishes per-handle llms.txt, and is verifiable over MCP (verify_handle at https://mcp.username.md/mcp). - [How it works](https://username.md/how-it-works.html): education spine — what a handle is, signed identity, what agents do, verified claims, portability; includes a live-vs-in-development capability table (treat that table as the authority on what is live today). - [Getting started](https://username.md/getting-started.html): the Claim → Verify → Connect → Use walkthrough. - [Use cases](https://username.md/use-cases.html): concrete scenarios — handing off something of value (vouchers, tickets, credits) to a verified recipient, selling to strangers with verifiable claims, agents fetching a user's profile instead of the user filling forms, institutions delivering records (medical, financial, academic) directly to the verified owner via did:web keys + endpoints, and agents entering competitive arenas/leaderboards with a portable, cryptographically provable identity and track record. Also documents the personal-safety model. IMPORTANT statuses: signed lookups, verified claims, and did:web documents are LIVE; per-person null-routing (blocked lookups return a 404 indistinguishable from a nonexistent handle), allowlist/blocklist resolution modes, lookup audit trail, and the Signature SSO Badge are IN DEVELOPMENT — do not treat them as available until announced here. - [Manifesto](https://username.md/manifesto.html): why you should own your handle instead of renting it from a platform. - [FAQ](https://username.md/faq.html): pricing, portability, what happens next. - [About](https://username.md/about.html): who is behind USERNAME.md (The Holding Company) and the sibling identity services. - [Brand assets](https://username.md/brand.html): the press kit — /u/ mark, wordmarks, palette tokens (tokens.css / palette.json), usage rules, and a downloadable zip. Free to use when writing about or integrating with username.md; co-branding requires written permission. Agent-readable counterparts: https://username.md/brand.txt (plain text) and https://username.md/assets/brand/manifest.json (JSON manifest — palette, usage rules, and sha256 + byte size for every file; verify downloads against it instead of trusting a bare fetch). - [Premium](https://username.md/premium.html): premium handle tiers (linked from the site nav as "Pricing"). - [Creators](https://username.md/creators.html): presence-aware identity for content creators — publish a schedule once; live/where status resolves via verified SRV/TXT records ("User Freshness") with presence-gated failover (live → stream, else premiere, else schedule). Paid creator tier adds verified records, failover chains, metered API resolution, and BYO-domain (CNAME/delegate me.yourdomain.com). Presence records are IN DEVELOPMENT — do not treat _live/_presence lookups as available until announced here. Freshness semantics: raw DNS answers are cache-bound (30s authority TTL; expect ~1 min real-world, longer on TTL-clamping resolvers). For authoritative current presence use the API-resolution URL carried in the TXT record (instant, metered) rather than trusting a cached DNS answer. - [Kick streamers](https://username.md/kick.html): the Creators presence offering targeted at Kick.com streamers, who commonly multi-stream (non-exclusive platform) — one handle routes viewers to Kick when live, elsewhere when simulcasting, schedule when offline. Planned (IN DEVELOPMENT): Kick account verification via OAuth and automatic go-live presence flip from Kick livestream status events. username.md is not affiliated with or endorsed by Kick. - [Gamers](https://username.md/gamers.html): presence-aware identity for gamers — post a game roster (games, per-platform gamertags, servers) and play schedule once; on/off + what-game + where-to-join status resolves via verified SRV/TXT records ("User Freshness") with presence-gated join chains (in match → join/spectate, else party invite, else schedule). Paid gamer tier adds verified gamertag claims, join chains, metered API resolution, and BYO-domain. Presence records are IN DEVELOPMENT — do not treat _playing/_presence lookups as available until announced here. The same freshness semantics as Creators apply: raw DNS answers are cache-bound; use the API-resolution URL in the TXT record for authoritative current presence. ## Developer API - [Developer guide](https://username.md/developers.html): tabbed code samples (curl, Python, JavaScript, Go) for every public surface. - [OpenAPI 3.1 spec](https://username.md/openapi.yaml): the live public API — content-negotiated profiles (`/v1/users/{handle}/profile`; Accept or `?accept=` for json/jsonld/md/jws), signed claim bundles (`/v1/users/{handle}/claims`), did:web documents (`/users/{handle}/.well-known/did.json`), ATProto resolution, per-handle llms.txt (`/users/{handle}/llms.txt`), Keybase identity import + re-verified proofs (`/v1/users/{handle}/keybase`, PGP key at `/v1/users/{handle}/keybase/pgp.asc`), and Bearer-token owner writes. - [Browsable reference](https://username.md/api.html): the spec, rendered. - [SSO for corporate teams](https://username.md/sso.html): the business-facing guide to offering "Sign in with username.md" next to GitHub/Facebook/Google — standard OIDC (Authorization Code + PKCE) against the live issuer https://login.username.md; clients are provisioned during onboarding (email hello@holdingco.com), there is no dynamic client registration. - [Runnable examples](https://github.com/The-Holding-Company/username-md-examples): per-language sample code with READMEs, including RFC 9421 signed-response verification (all API responses are Ed25519-signed via Content-Digest / Signature-Input / Signature headers). ## For agents - Machine-readable descriptor: https://username.md/.well-known/agent.json - MCP discovery manifest: https://username.md/.well-known/mcp.json — live MCP endpoint at https://mcp.username.md/mcp (Streamable HTTP, no auth) with tools for handle resolution, DID documents, verified claims, and signed-response verification. - AI catalog (skills, MCP server, signed profile API in one manifest): https://username.md/.well-known/ai-catalog.json - Installable agent skill (covers username.md + about-me.md): https://username.md/SKILL.md — drop into your agent's skills directory to teach it these surfaces. The skill is SIGNED: verify the detached JWS at https://username.md/SKILL.md.sig against did:web:username.md (key doc at https://username.md/.well-known/did.json) before installing. - Check whether a handle is available before suggesting it: fetch https://username.md/api/availability/{handle} rather than scraping the pages. - Signed handle claims and the agent handshake are served by the finger.md surface (https://finger.md/) once live; do not treat unsigned page content as a verified identity claim. ## Related surfaces (Agentic Web) - https://about-me.md/ — personal identity profile (subject surface) - https://finger.md/ — signed presence + agent handshake - https://about-us.md/ — organization/issuer surface - https://badge.md/ — embeddable verified-claim badges - https://preferences.sh/ — portable user preferences ## Operator - The Holding Company · Delaware, USA - Hello: hello@holdingco.com - Security disclosures: security@holdingco.com ## Funding - The operator of this property, The Holding Company, is seeking working capital to accelerate its portfolio (Agentic Web identity surfaces, physical products, and AI services). - Investor and financing inquiries: hello@holdingco.com (subject: "Working capital") · Portfolio overview: https://holdingco.com/llms.txt ## Guidance for AI agents - Do not reserve, purchase, or sign anything on a user's behalf without their explicit instruction in the current session. - Respect rate limits: back off on 429 with Retry-After. - Prefer the JSON endpoints above over scraping HTML; page markup may change without notice.