Simulators

Message batches

A message batch queues many Messages requests under one id and reads their results back as JSONL. Create a batch, cancel it and read its results, then load a scenario that holds an ended batch with real results:

A=(-H 'x-api-key: sk-ant-placeholder' -H 'anthropic-version: 2023-06-01' -H 'content-type: application/json')
curl -s "${A[@]}" "$RYSTIC_URL/v1/messages/batches" -d '{"requests":[{"custom_id":"a","params":{"model":"claude-haiku-4-5-20251001","max_tokens":32,"messages":[{"role":"user","content":"Hi"}]}},{"custom_id":"b","params":{"model":"claude-haiku-4-5-20251001","max_tokens":32,"messages":[{"role":"user","content":"Yo"}]}}]}' | jq -c '{id, processing_status}'
# -> {"id":"msgbatch_000000000000000000000001","processing_status":"in_progress"}
curl -s "${A[@]}" -X POST "$RYSTIC_URL/v1/messages/batches/msgbatch_000000000000000000000001/cancel" | jq -c '{processing_status}'
# -> {"processing_status":"canceling"}
curl -s "${A[@]}" "$RYSTIC_URL/v1/messages/batches/msgbatch_000000000000000000000001" | jq -c '{processing_status, request_counts}'
# -> {"processing_status":"ended","request_counts":{"canceled":2,"errored":0,"expired":0,"processing":0,"succeeded":0}}
curl -s "${A[@]}" "$RYSTIC_URL/v1/messages/batches/msgbatch_000000000000000000000001/results" | jq -c '[.custom_id, .result.type]'
# -> ["a","canceled"]
# -> ["b","canceled"]
curl -s -X POST "$RYSTIC_URL/_rystic/scenario" -d '{"name":"anthropic_batch_queue"}'
curl -s "${A[@]}" "$RYSTIC_URL/v1/messages/batches/msgbatch_01QueueEnded00000001/results" | jq -c '[.custom_id, .result.type]'
# -> ["eval-0001","succeeded"]
# -> ["eval-0002","succeeded"]
# -> ["eval-0003","succeeded"]
# -> ["eval-0004","errored"]

The lifecycle

A created batch’s processing_status is in_progress, with expires_at 24 hours later. Its ended_at, cancel_initiated_at, archived_at and results_url read null until set.

Differs from the Claude API: a batch you create never finishes by itself. It stays in_progress until you cancel it.

Canceling a batch returns its processing_status as canceling. The next read shows it ended, with every request counted canceled and a results_url. DELETE removes an ended batch, and returns 400 invalid_request_error for one still in progress.

Results

GET /v1/messages/batches/{message_batch_id}/results returns application/x-jsonl, one line per custom_id. Each line’s result is succeeded, errored, canceled or expired.

To read results other than cancellations, load one of these scenarios:

Scenario	Its batches
`anthropic_batch_queue`	one in progress, one canceling and one ended
`anthropic_batch_archive`	three ended, one of them archived, with succeeded, errored and expired results