Errors and limits

The error shape every surface returns, what each status class means, the codes worth branching on, and the plan and rate limits a call can meet.

The error shape

Every error from the REST API has the same body:

{
  "error": {
    "code": "unknown_approver",
    "message": "A sentence for a person to read.",
    "details": { "…": "whatever the refusal carries, when it carries something" }
  }
}

The `code` is the contract. Branch on it, never on the message, which is written for people and will be reworded. The SDKs raise it as DeliverdError.code, the CLI prints Error (code): message, and the MCP server returns most refusals as an error result carrying the same code.

Status classes

Status	Means	What to do
400	The request itself is wrong.	Change it. Retrying the same request fails the same way.
401	The credential was not accepted.	Check the key or token.
402	Your plan does not include this, or a plan limit is reached.	Upgrade, or free something up. Not retryable as it is.
403	A refusal about you, or a rule about you.	Not retryable. Read the code: a missing scope, a role, or an organisation rule.
404	No such thing, or nothing this key may see.	Check the id. The two are deliberately indistinguishable.
409	The request was fine and the world moved.	Re-read and retry: someone published first, a question was answered, a version is awaiting approval.
413, 415, 422	The body is too large, the wrong type, or a scan blocked what was in it.	Change the content.
429	Too many requests.	Slow down and retry; the SDKs do this for you.
500	Ours.	Retry later. A named `500` code means a write failed for a reason you could not have avoided.

Codes worth branching on

Code	Status	When
`auth_error`	401 or 403	The key or token is missing, malformed, revoked or expired (401), or its organisation is suspended or its agent disabled (403).
`insufficient_scope`	403	The credential is fine and lacks the scope this call needs; the message names it. Reissue the key — scopes are fixed when a key is made.
`validation_error`	400	The body does not match the schema; `details` lists the problems.
`unknown_approver`	400	An approver, reviewer or respondent is not someone the organisation knows.
`ambiguous_approver`	400	A name matches more than one person or team. Name it by id.
`self_approval`	403	The requester named only themselves.
`refused_by_rule`	403	An organisation rule or ethics rule refused the request. The message carries its explanation.
`action_not_permitted`	403	This agent is not permitted to make this kind of request.
`agent_not_permitted`	403	Agent keys may not do this: registering actions, writing policy.
`not_permitted`	403	Your role does not allow this, whatever the key's scopes.
`agent_not_found`	404	The agent this key acts as has been deleted.
`unknown_action`	404	The gate was asked about an action nobody registered.
`invalid_input`	400	The gate's input does not match the action's schema; `problems` names each fault.
`question_not_found`	404	That question is not on this approval.
`already_answered`	409	Somebody has already answered that question.
`version_conflict`	409	`expectedVersion` is stale: somebody published first.
`approval_pending`	409	A version of this report is awaiting approval.
`upload_not_found`	404	The upload ticket is gone — usually because the first publish used it.
`scan_blocked`	422	The publish scan found something it will not serve.
`public_sharing_denied`	403	Agent keys cannot create public links.
`invalid_cursor`	400	A list cursor this API did not issue.
`idempotency_key_reused`	422	The same `Idempotency-Key` with a different body.
`idempotency_in_progress`	409	The first request with this key has not finished. Retry with the same key.
`rate_limited`	429	Too many requests from this key.

The gate's refusal is not on this list, because it is not an error: a denied action answers 200 with allowed: false. See The gate.

Plan limits

A call that needs something your plan does not include, or that would take you past a limit, answers 402:

Code	Status	When
`feature_unavailable`	402	The plan does not include this capability — agent identities, for example.
`plan_required`	402	Organisation-wide analytics, below the plan that includes it.
`plan_limit`	402	The plan's number of live reports is reached. Archive one or upgrade.
`storage_limit`	402	Storing this version would pass the plan's storage.
`seat_limit`	402	The plan's number of seats is reached.
`limit_reached`	402	The plan's number of report schedules is reached. A schedule records when an agent should publish; the agent runs elsewhere.

	Free	Team	Business Starter	Business	Enterprise
Approval requests a month	100	Unlimited	Unlimited	Unlimited	Unlimited
Live reports	10	200	500	1,000	Unlimited
Seats	2	10	20	50	200
Storage	1 GB	25 GB	50 GB	100 GB	500 GB
Report schedules	—	2	5	10	100
Model screens a month	—	—	500	1,000	10,000

Your organisation's actual limits are on Organisation → Billing; an Enterprise agreement can change them.

Rate limits

Each API key or token may make up to 120 requests a minute. Past that, calls answer 429 rate_limited until the minute is up. The SDKs retry a 429 with backoff, honouring Retry-After, and their polling starts quick and slows down, so an agent waiting on a person does not spend its allowance.

Retrying safely

Retry 409, 429 and 5xx. Do not retry other 4xx without changing the request.
Send an Idempotency-Key on every POST and keep it across your retries, so a request that arrives twice is done once. The SDKs do this for you. A 5xx releases the key, so your retry is a real attempt.
Give requests an externalId so a restarted agent can find what it already asked rather than asking twice. The gate requires one.

Try it on your own agent.

Free to start, no card. Sign up with Google, Microsoft or GitHub, and the first page after hands you an API key.

Start free →

The error shape#

Status classes#

Codes worth branching on#

Plan limits#

Rate limits#

Retrying safely#