Errors

Every error has the same shape, with a code you can rely on:

{
  "type": "about:blank",
  "title": "Conflict",
  "status": 409,
  "code": "condition_reused",
  "detail": "executionCondition is already used by another quote"
}

Build your handling around code. title and detail are written for people and may change. New codes may be added over time, so handle a code you don’t recognize by its HTTP status.

Error codes

Code	Status	What it means	What to do
`invalid_request`	400	Something in the request is wrong.	`detail` names the field. Fix it and send again.
`unsupported_chain`	400	The chain isn’t supported, or not for this kind of swap.	Use a chain from `GET /v1/chains`.
`unsupported_asset`	400	The token doesn’t exist on that chain.	Check the token address.
`amount_too_small`	400	A private swap is worth less than the $20 minimum.	Sell more.
`amount_too_large`	400	The amount is too large to hold in a single swap.	Sell less.
`invalid_fulfillment`	400	The secret doesn’t match the hash this quote was made with.	Send the secret you stored with this quote.
`unauthorized`	401	The API key is malformed, unknown, or revoked, or its account is suspended.	Check the key, or send the request without one.
`not_found`	404	No such endpoint.	Check the path.
`quote_not_found`	404	No quote has this ID.	Check the ID. Only firm quotes have one.
`method_not_allowed`	405	The endpoint doesn’t accept this method.	Check the method.
`condition_reused`	409	An earlier quote already used this secret’s hash.	Create a new secret and request a new quote.
`quote_expired`	409	A private swap was submitted after its quote expired.	Get a new quote.
`not_ready`	409	A request with this `Idempotency-Key` is still running, or a private swap was already submitted.	Try again shortly, or check the swap’s status.
`destination_not_ready`	409	The solver’s tokens can’t be paid out yet.	Wait a few seconds and reveal again with the same key.
`payload_too_large`	413	The request is too big.	Send a smaller request.
`no_route`	422	No solver or aggregator offered a price for this swap.	Try a different amount or pair, or try again later.
`invalid_private_transaction`	422	A private swap didn’t pass Tern’s checks. `detail` says which one.	Check the actions, prepare the transaction again, and resubmit.
`rate_limited`	429	Too many requests.	Wait for the seconds in `Retry-After`. See Rate limits.
`internal`	500	Something went wrong on Tern’s side.	Try again after a short wait, with the same `Idempotency-Key`.
`timeout`	503	The request took longer than 10 seconds, or a price it needed wasn’t available.	Try again after a short wait, with the same `Idempotency-Key`.

When to retry

Safe to retry as is: 409 not_ready, 409 destination_not_ready, 429, 500, and 503. Use the same Idempotency-Key if the request has one.
If you didn’t get an answer: a timeout or dropped connection doesn’t mean the request failed. Retry with the same Idempotency-Key until you get a response, rather than starting over. See Idempotency.
Fix first: every other 4xx error, including 409 condition_reused and 409 quote_expired, means the request has to change before you send it again.

When you report a problem, include the response’s x-request-id.

Overview

Quotes

Chains

Indexing

Error codes

When to retry

​Error codes

​When to retry

Error codes

When to retry