| name | arize-dataset |
|---|---|
| description | INVOKE THIS SKILL when creating, managing, or querying Arize datasets and examples. Covers dataset CRUD, appending examples, exporting data, and file-based dataset creation using the ax CLI. |
- Dataset = a versioned collection of examples used for evaluation and experimentation
- Dataset Version = a snapshot of a dataset at a point in time; updates can be in-place or create a new version
- Example = a single record in a dataset with arbitrary user-defined fields (e.g.,
question,answer,context) - Space = an organizational container; datasets belong to a space
System-managed fields on examples (id, created_at, updated_at) are auto-generated by the server -- never include them in create or append payloads.
Proceed directly with the task — run the ax command you need. Do NOT check versions, env vars, or profiles upfront.
If an ax command fails, troubleshoot based on the error:
command not foundor version error → see references/ax-setup.md401 Unauthorized/ missing API key → runax profiles showto inspect the current profile. If the profile is missing or the API key is wrong: check.envforARIZE_API_KEYand use it to create/update the profile via references/ax-profiles.md. If.envhas no key either, ask the user for their Arize API key (https://app.arize.com/admin > API Keys)- Space ID unknown → check
.envforARIZE_SPACE_ID, or runax spaces list -o json, or ask the user - Project unclear → check
.envforARIZE_DEFAULT_PROJECT, or ask, or runax projects list -o json --limit 100and present as selectable options
Browse datasets in a space. Output goes to stdout.
ax datasets list
ax datasets list --space-id SPACE_ID --limit 20
ax datasets list --cursor CURSOR_TOKEN
ax datasets list -o json| Flag | Type | Default | Description |
|---|---|---|---|
--space-id |
string | from profile | Filter by space |
--limit, -l |
int | 15 | Max results (1-100) |
--cursor |
string | none | Pagination cursor from previous response |
-o, --output |
string | table | Output format: table, json, csv, parquet, or file path |
-p, --profile |
string | default | Configuration profile |
Quick metadata lookup -- returns dataset name, space, timestamps, and version list.
ax datasets get DATASET_ID
ax datasets get DATASET_ID -o json| Flag | Type | Default | Description |
|---|---|---|---|
DATASET_ID |
string | required | Positional argument |
-o, --output |
string | table | Output format |
-p, --profile |
string | default | Configuration profile |
| Field | Type | Description |
|---|---|---|
id |
string | Dataset ID |
name |
string | Dataset name |
space_id |
string | Space this dataset belongs to |
created_at |
datetime | When the dataset was created |
updated_at |
datetime | Last modification time |
versions |
array | List of dataset versions (id, name, dataset_id, created_at, updated_at) |
Download all examples to a file. Use --all for datasets larger than 500 examples (unlimited bulk export).
ax datasets export DATASET_ID
# -> dataset_abc123_20260305_141500/examples.json
ax datasets export DATASET_ID --all
ax datasets export DATASET_ID --version-id VERSION_ID
ax datasets export DATASET_ID --output-dir ./data
ax datasets export DATASET_ID --stdout
ax datasets export DATASET_ID --stdout | jq '.[0]'| Flag | Type | Default | Description |
|---|---|---|---|
DATASET_ID |
string | required | Positional argument |
--version-id |
string | latest | Export a specific dataset version |
--all |
bool | false | Unlimited bulk export (use for datasets > 500 examples) |
--output-dir |
string | . |
Output directory |
--stdout |
bool | false | Print JSON to stdout instead of file |
-p, --profile |
string | default | Configuration profile |
Agent auto-escalation rule: If an export returns exactly 500 examples, the result is likely truncated — re-run with --all to get the full dataset.
Export completeness verification: After exporting, confirm the row count matches what the server reports:
# Get the server-reported count from dataset metadata
ax datasets get DATASET_ID -o json | jq '.versions[-1] | {version: .id, examples: .example_count}'
# Compare to what was exported
jq 'length' dataset_*/examples.json
# If counts differ, re-export with --allOutput is a JSON array of example objects. Each example has system fields (id, created_at, updated_at) plus all user-defined fields:
[
{
"id": "ex_001",
"created_at": "2026-01-15T10:00:00Z",
"updated_at": "2026-01-15T10:00:00Z",
"question": "What is 2+2?",
"answer": "4",
"topic": "math"
}
]Create a new dataset from a data file.
ax datasets create --name "My Dataset" --space-id SPACE_ID --file data.csv
ax datasets create --name "My Dataset" --space-id SPACE_ID --file data.json
ax datasets create --name "My Dataset" --space-id SPACE_ID --file data.jsonl
ax datasets create --name "My Dataset" --space-id SPACE_ID --file data.parquet| Flag | Type | Required | Description |
|---|---|---|---|
--name, -n |
string | yes | Dataset name |
--space-id |
string | yes | Space to create the dataset in |
--file, -f |
path | yes | Data file: CSV, JSON, JSONL, or Parquet |
-o, --output |
string | no | Output format for the returned dataset metadata |
-p, --profile |
string | no | Configuration profile |
Use --file - to pipe data directly — no temp file needed:
echo '[{"question": "What is 2+2?", "answer": "4"}]' | ax datasets create --name "my-dataset" --space-id SPACE_ID --file -
# Or with a heredoc
ax datasets create --name "my-dataset" --space-id SPACE_ID --file - << 'EOF'
[{"question": "What is 2+2?", "answer": "4"}]
EOFTo add rows to an existing dataset, use ax datasets append --json '[...]' instead — no file needed.
| Format | Extension | Notes |
|---|---|---|
| CSV | .csv |
Column headers become field names |
| JSON | .json |
Array of objects |
| JSON Lines | .jsonl |
One object per line (NOT a JSON array) |
| Parquet | .parquet |
Column names become field names; preserves types |
Format gotchas:
- CSV: Loses type information — dates become strings,
nullbecomes empty string. Use JSON/Parquet to preserve types. - JSONL: Each line is a separate JSON object. A JSON array (
[{...}, {...}]) in a.jsonlfile will fail — use.jsonextension instead. - Parquet: Preserves column types. Requires
pandas/pyarrowto read locally:pd.read_parquet("examples.parquet").
Add examples to an existing dataset. Two input modes -- use whichever fits.
Generate the payload directly -- no temp files needed:
ax datasets append DATASET_ID --json '[{"question": "What is 2+2?", "answer": "4"}]'
ax datasets append DATASET_ID --json '[
{"question": "What is gravity?", "answer": "A fundamental force..."},
{"question": "What is light?", "answer": "Electromagnetic radiation..."}
]'ax datasets append DATASET_ID --file new_examples.csv
ax datasets append DATASET_ID --file additions.jsonax datasets append DATASET_ID --json '[{"q": "..."}]' --version-id VERSION_ID| Flag | Type | Required | Description |
|---|---|---|---|
DATASET_ID |
string | yes | Positional argument |
--json |
string | mutex | JSON array of example objects |
--file, -f |
path | mutex | Data file (CSV, JSON, JSONL, Parquet) |
--version-id |
string | no | Append to a specific version (default: latest) |
-o, --output |
string | no | Output format for the returned dataset metadata |
-p, --profile |
string | no | Configuration profile |
Exactly one of --json or --file is required.
- Each example must be a JSON object with at least one user-defined field
- Maximum 100,000 examples per request
Schema validation before append: If the dataset already has examples, inspect its schema before appending to avoid silent field mismatches:
# Check existing field names in the dataset
ax datasets export DATASET_ID --stdout | jq '.[0] | keys'
# Verify your new data has matching field names
echo '[{"question": "..."}]' | jq '.[0] | keys'
# Both outputs should show the same user-defined fieldsFields are free-form: extra fields in new examples are added, and missing fields become null. However, typos in field names (e.g., queston vs question) create new columns silently -- verify spelling before appending.
ax datasets delete DATASET_ID
ax datasets delete DATASET_ID --force # skip confirmation prompt| Flag | Type | Default | Description |
|---|---|---|---|
DATASET_ID |
string | required | Positional argument |
--force, -f |
bool | false | Skip confirmation prompt |
-p, --profile |
string | default | Configuration profile |
Users often refer to datasets by name rather than ID. Resolve a name to an ID before running other commands:
# Find dataset ID by name
ax datasets list -o json | jq '.[] | select(.name == "eval-set-v1") | .id'
# If the list is paginated, fetch more
ax datasets list -o json --limit 100 | jq '.[] | select(.name | test("eval-set")) | {id, name}'- Prepare a CSV/JSON/Parquet file with your evaluation columns (e.g.,
input,expected_output)- If generating data inline, pipe it via stdin using
--file -(see the Create Dataset section)
- If generating data inline, pipe it via stdin using
ax datasets create --name "eval-set-v1" --space-id SPACE_ID --file eval_data.csv- Verify:
ax datasets get DATASET_ID - Use the dataset ID to run experiments
# Find the dataset
ax datasets list
# Append inline or from a file (see Append Examples section for full syntax)
ax datasets append DATASET_ID --json '[{"question": "...", "answer": "..."}]'
ax datasets append DATASET_ID --file additional_examples.csvax datasets list-- find the datasetax datasets export DATASET_ID-- download to file- Parse the JSON:
jq '.[] | .question' dataset_*/examples.json
# List versions
ax datasets get DATASET_ID -o json | jq '.versions'
# Export that version
ax datasets export DATASET_ID --version-id VERSION_ID- Export current version:
ax datasets export DATASET_ID - Modify the examples locally
- Append new rows:
ax datasets append DATASET_ID --file new_rows.csv - Or create a fresh version:
ax datasets create --name "eval-set-v2" --space-id SPACE_ID --file updated_data.json
# Count examples
ax datasets export DATASET_ID --stdout | jq 'length'
# Extract a single field
ax datasets export DATASET_ID --stdout | jq '.[].question'
# Convert to CSV with jq
ax datasets export DATASET_ID --stdout | jq -r '.[] | [.question, .answer] | @csv'Examples are free-form JSON objects. There is no fixed schema -- columns are whatever fields you provide. System-managed fields are added by the server:
| Field | Type | Managed by | Notes |
|---|---|---|---|
id |
string | server | Auto-generated UUID. Required on update, forbidden on create/append |
created_at |
datetime | server | Immutable creation timestamp |
updated_at |
datetime | server | Auto-updated on modification |
| (any user field) | any JSON type | user | String, number, boolean, null, nested object, array |
- arize-trace: Export production spans to understand what data to put in datasets → use
arize-trace - arize-experiment: Run evaluations against this dataset → next step is
arize-experiment - arize-prompt-optimization: Use dataset + experiment results to improve prompts → use
arize-prompt-optimization
| Problem | Solution |
|---|---|
ax: command not found |
See references/ax-setup.md |
401 Unauthorized |
API key is wrong, expired, or doesn't have access to this space. Fix the profile using references/ax-profiles.md. |
No profile found |
No profile is configured. See references/ax-profiles.md to create one. |
Dataset not found |
Verify dataset ID with ax datasets list |
File format error |
Supported: CSV, JSON, JSONL, Parquet. Use --file - to read from stdin. |
platform-managed column |
Remove id, created_at, updated_at from create/append payloads |
reserved column |
Remove time, count, or any source_record_* field |
Provide either --json or --file |
Append requires exactly one input source |
Examples array is empty |
Ensure your JSON array or file contains at least one example |
not a JSON object |
Each element in the --json array must be a {...} object, not a string or number |
See references/ax-profiles.md § Save Credentials for Future Use.