Errors

Failures answer JSON with an error string meant to be shown to a person, and a request_id matching the X-Request-ID header. Where the platform can classify a refusal it adds reason, one word to switch on, and some routes add code for a route-specific detail; match on those, never on the sentence. An endpoint that adds to this table lists what it adds under Failures in its entry in the reference.

400

The request was malformed — a bad resolution string, a missing command, a {pid} or {window} that is not one. It is also what a well-formed request gets when the thing it names cannot be acted on and never will be — a restore onto a computer that is gone, for instance. Either way it is final: the message says what is wrong, and sending it again unchanged answers the same. That is the whole difference from a 503, which means ask again shortly.

401

Platform authentication required or refused: reason is missing, invalid, or revoked, with WWW-Authenticate: Bearer (invalid_token for invalid/revoked).

402

Your plan refused this: a quota, or a payment that has not gone through. On an agent run it can instead be Insufficient AI credits with top_up_url (a run funded by the account’s AI credits), or the model provider’s own billing refusal of your X-Model-Key, relayed.

403

The credential is recognized but its holder lacks the required role or membership, or the holder/account is suspended, or the holder has not verified their email address. An ordinary denial for too low a role may carry no reason. The email one carries none either, and its message begins Verify your email before: it answers a create, a clone of a computer or a snapshot, a new API key and a new SSH key, and is cleared by verifying the address in the dashboard. reason: "revoked" marks authority that is gone: a suspended account or a lost membership (refused as the request arrives, or if it happens while the request is in flight), or a role that was lowered while the request was in flight. The message identifies the refusal; replacing a valid key alone does not restore authority, and sending the same call again does not help.

404

No such resource in your scope — a computer, snapshot, secret, webhook, SSH key, API key, workspace, operation and so on — or no such endpoint; a confirmed missing guest file is no such file in the guest.

405

This public path exists but does not accept that method. Allow lists only its public methods, with HEAD for GET and metadata OPTIONS.

409

Refused for the state something is in — resizing a computer that is running, running a command on one that is stopped, taking a snapshot while another capture of it is running.

WHETHER RETRYING HELPS IS IN THE BODY, NOT THE STATUS, and this is the one thing to take from this entry. Some of these describe a state that is passing: a guest agent still inside its boot window, a guest agent busy with another call, a move already running on the account. Those clear on their own and the same request works a moment later. The rest describe a DECISION about the request you sent — the size does not fit, the computer is the wrong one for this, the saved session cannot travel — and no amount of retrying turns one of those into a yes. A client that treats 409 as uniformly transient loops forever on half of them.

Where the platform can say which it is, it sends reason beside error — one word, meant to be switched on rather than read: contention and starting clear on their own, unavailable means the computer is not running and only starting it helps, running means the computer is running and only stopping it helps (a resize), unsupported means waiting will not change the answer — this computer cannot do it at all, or it needs another step first, which the message names (a stop, or removing its secret bindings, for example) — exists means a create-only upload found its path taken, name_taken means a secret of that name is already in that scope, stale_revision means a secret changed since the revision_id you sent was read (or a computer’s bound list since the version you sent), and stale_capture means the screenshot capture you named is no longer held: a newer one replaced it, or its host’s daemon restarted or the computer moved. starting covers the two minutes after a start or a restart, and after a reboot from inside the guest on a computer last cold-started recently enough to report one (a stop and a start gives an older one that); a guest agent that is still silent after that is a 502. Match on that and never on the sentence, which is prose and is rewritten. Absent means no classification was given — treat it, and any word you do not recognise, as no answer, because not every refusal here has one yet. It is what the guest routes answer: the clipboard on a stopped computer used to be a 409 indistinguishable from a clipboard whose selection was claimed for an instant, and a blanket retry loop spun against the first until its deadline.

Every 409 that clears on its own carries contention or starting: a host busy with another build or with no room for one, an operation already running on the same computer or snapshot (a capture, a copy, a delete, a restore or clone reading it, another agent run), a lock another request holds, a move or a delivery settling. So a 409 with no word, or with any other word, is not one that waiting fixes: read the sentence for the step it names.

The ones worth knowing by name, because each has a next step that is not "wait":

A resize past what the computer’s host can run carries move, an object rather than a message: {"required":true,"possible":true} means another host in this region could run it and the computer has to be moved there first — POST /computers/{id}/move with the same sizing fields is how you agree to that, and it is a separate call because relocating a computer is not something a resize should do to you quietly. possible:false means nowhere in the region can, and the size is the thing to change.

The move itself then refuses for the things it re-decides at the moment it runs, and only one of those is worth waiting on: a computer that is running or suspended has to be stopped or resumed-and-stopped by you, a size that fits where it already is wants an ordinary resize instead, and a region with nowhere to put it wants a smaller size. Another computer on this account is being moved right now is the one that clears by itself, and it carries reason: "contention" — one move runs per account, and GET /moves says which.

And the terminal socket refuses twice over: reason: "unavailable" with resume_required: true on a suspended computer, which clears when you start it and not before, and reason: "unsupported" on a running computer whose hardware carries no terminal channel — one last started before interactive terminals existed — which needs a stop and a start. Not a restart, which resets the same machine, and not a retry, which never comes good.

413

What you sent, or asked for, is past a size limit. A JSON request body is capped at 1 MiB unless the route states its own limit: POST /computers/{id}/exec takes up to 4 MiB, and some routes take less; guest file transfers, template documents and the clipboard have limits of their own. The message names the limit that applied.

416

Your Range named no byte the file has. The Content-Range on the refusal carries the file’s actual length, so you can ask again without guessing.

422

The Idempotency-Key on this request was used within its 24 hours with a different request (code: "idempotency_key_reused"). Nothing was done: a key stands for one request, so send this one under a new key.

429

You are asking faster than your plan allows. Retry-After says how many seconds to wait, and every metered response — anything past authentication and the re-check that your credential’s authority still holds — carries RateLimit-Remaining, so you do not have to be refused to find out. A 401, a 403 from that re-check, an OPTIONS answer and an unexpected 500 carry none. The budget is spent in proportion to what a call costs rather than per request. What a call costs, in budget units, by kind (each operation’s exact figure is its x-rate-cost in the OpenAPI document): 1 to read one thing; 5 for a listing that spans the fleet, and 5 for a call into a running guest such as a screenshot or an exec; 10 for a power change and 10 to move file bytes; 25 for GET /usage, GET /credits, creating a public URL, and creating, rotating or testing a webhook; 50 to capture a snapshot; 100 to create, clone or restore a computer, and 100 to start an agent run, whose actions are then charged as they happen. The account-wide budget, as what an idle caller may spend at once and what refills each minute: No plan 1200 at once and 1200 a minute; Solo 4800 at once and 4800 a minute; Studio 12000 at once and 12000 a minute; Swarm 21600 at once and 21600 a minute. A single API key gets half of either. A 401 for a missing or unusable credential costs nothing: it is refused before anything is metered. A few refusals at the door cost one unit: a 403 because the role is too low or the route refuses an API key confined to a workspace, a 404 for a path that matches nothing, a 405, and an Idempotency-Key answered from its stored result or still in progress. Everything else is charged in full when it is admitted, before it is carried out, so a refusal after that has spent the whole cost: a 400, 402 or 409 from the route, a 403 its handler sends (on most routes, a suspended account included), and a model provider’s 401 on an agent run. The budget belongs to the account and is shared across everything on it, and any single API key may spend at most half of it. RateLimit-Limit is whichever of those two is binding on the request that carried it — usually the per-key half, and the account-wide figure when other keys have already spent more of it than this one has. All three RateLimit-* headers describe the same one, so limit minus remaining is what has been spent against it. A few 429s are not about this budget, say so in their message, and can carry no Retry-After: a model provider’s rate limit relayed on an agent run. The cap on forks of one snapshot waiting for their secrets sends its own bounded expiry-based Retry-After with reason: "contention" (see POST /snapshots/{id}/clone).

500

The application could not finish this: an unexpected exception, a build that broke, or a storage fault. Application refusals carry the request correlation ID; unexpected internal details are not returned.

501

This feature is not available: no hypervisor in the fleet can build a template, or the platform or the host holding this computer does not offer it. Unlike a 409, this does not clear on its own — retrying will not help, so treat it as an outage of the feature rather than of the moment.

502

The agent inside the guest is not answering, or it rejected or malformed the private command protocol for this feature. The computer is up; the upstream agent interaction failed. This is not malformed caller input and carries no retry classification.

503

Something this depends on — a hypervisor, a store, or a host’s capacity — could not answer or take this right now. A read can be retried shortly. A change answered 503 may or may not have happened — a failure after the request was sent is answered the same way, with or without a warning in the message — so read the current state before retrying anything that is not safe to repeat, such as a create or a command. On the collection reads, allow_partial=1 accepts a knowingly short answer instead.

504

The operation did not finish before its deadline — a window action the guest accepted but did not report on, or an artifact read or delete. It may already have happened, so this is an uncertain outcome rather than permission to repeat it: check before sending it again.