Is the Anthropic API reachable right now?

A live probe of api.anthropic.com from NetOkay’s edge, and how to tell a Claude API incident from an idle timeout on your own path.

In short: The card below sends a keyless GET to api.anthropic.com/v1/messages. Anthropic’s edge usually refuses it with a 403 in milliseconds; a 405 means the request reached the Messages endpoint and was rejected for using GET. Both mean the host answered. If it answers here but your stream dies, check your network’s idle handling.

Last updated 15 September 2026

Live probe · NetOkay Worker → api.anthropic.com

Right now, from NetOkay’s edge

Loading the latest observation of api.anthropic.com…

One keyless GET to https://api.anthropic.com/v1/messages, cached for a minute per Cloudflare location. On a healthy day this probe sees HTTP 403 from Anthropic’s edge for a keyless automated request, or 405 when the request reaches the Messages endpoint itself.

Run the full website check →Test this browser →Compare environments →

What this probe shows, and what it does not

The NetOkay Worker resolves api.anthropic.com through Cloudflare DNS, opens a TLS connection and sends one GET without credentials, following no redirects. Any HTTP status, including 401, 403 or 405, means the host answered. Several providers refuse keyless automated requests at their edge with a 403 in a few milliseconds; that still proves DNS, TLS and the front door, but it is the provider’s edge answering, not necessarily the API application behind it. The result is one observation from one Cloudflare location, refreshed at most once a minute and never stored.

It cannot see your API key, quota, region, model availability or account state, and it does not travel your network path. A healthy probe and a failing application are compatible; the sections below are for that case.

Anthropic specifics

API host: api.anthropic.com, HTTPS on port 443. The Messages API lives at /v1/messages and accepts POST only. A keyless GET is usually stopped at Anthropic’s edge with 403; when it reaches the endpoint it gets 405. Both are healthy answers.
Streaming: Messages stream as server-sent events with named event types: message_start, content_block_start, content_block_delta, content_block_stop, message_delta, message_stop. Anthropic also sends periodic ping events, so a healthy stream is rarely silent for long.
Thinking pauses: With extended thinking enabled, thinking_delta events can arrive slowly and the final text block can come after a long gap. If your client only counts text deltas as progress, it may treat that gap as a hang.
Error codes: 401 invalid key; 403 permission; 429 rate limit; 529 overloaded, which is Anthropic‑specific and means retry with backoff, not that the host is down. Streamed requests can also deliver an error event mid‑stream.
Official status: status.anthropic.com (it redirects to status.claude.com) lists API and console incidents.

Reachable here but failing for you?

Run the homepage checks from the network where the app fails. The 30‑second idle stream shows whether something on your path closes silent connections, which is what a long model pause looks like to a proxy.
Read the idle result. Closed during the silence points at a proxy, gateway or NAT idle limit under 30 seconds. Start and done arriving together points at response buffering. Both have fixes in the streaming guide.
Compare environments. If the browser passes and a container, server or agent fails, compare the public IP each one uses, then run the CLI from the failing environment against api.anthropic.com.

Anthropic API status FAQ

Is a 403 or 405 from the probe a problem?

No. A 403 in milliseconds is Anthropic’s edge refusing a keyless automated request; a 405 means the GET reached the POST-only Messages endpoint. Both show DNS, TLS and the front door are working from Cloudflare’s edge, which is what the probe is for.

Claude streams fine for short answers but breaks on long ones. Why?

Long answers and extended thinking make the stream last longer, so any idle or total‑duration limit on your path becomes visible. Run the homepage idle stream check; a failure there points at your proxy or gateway, not at Anthropic.

What does 529 mean?

Anthropic returns 529 when the API is temporarily overloaded. It is an HTTP response, so connectivity is fine; back off and retry rather than debugging your network.