## Create a span

`client.Spans.New(ctx, body) (*Span, error)`

**post** `/v5/spans`

Create a single span and return the persisted span.

Use this for one-off span ingestion; to write many spans in one request use
POST /v5/spans/batch. When `id` is omitted the server generates a UUID.
Depending on per-account server configuration the span is persisted to the
legacy trace store, to the tracing service, or both. `end_timestamp`
must not precede `start_timestamp`, which is rejected with a 422. When the
tracing service is the primary store, its 400, 413 and 422 rejections keep that
status and detail, as does a 403 when the request carried its own API key, and
every other failure returns a 503 with a Retry-After header. A span whose parent
belongs to another trace is rejected with 409 before either store is written. The
parent is looked up in Postgres, so that check ends once the account's spans stop
being written there. Which writes the tracing service rejects depends in part on
its storage engine: on Postgres deployments a NUL byte or invalid UTF-8 inside
`trace_id`, `id`, `parent_id` or `group_id` rejects the span with a 400
naming the field, because replacing the byte would change the identity the
response echoes; a NUL byte or invalid UTF-8 in any other field is replaced with
U+FFFD and the span is persisted. ClickHouse deployments store the bytes verbatim.

Credential redaction: values in the free-form `input`, `output`, `metadata`,
and `expected` objects, and in `name`, that are credential-shaped (bearer/JWT,
API keys, connection-string passwords) or under a credential-named key are replaced
with `[REDACTED:credential]` before the span is persisted, so the stored and
returned span reflects the redacted value (EY 12.3).

### Parameters

- `body SpanNewParams`

  - `SpanCreate param.Field[SpanCreate]`

### Returns

- `type Span struct{…}`

  - `ID string`

  - `AccountID string`

  - `Name string`

  - `StartTimestamp Time`

  - `TraceID string`

    id for grouping traces together, uuid is recommended

  - `ApplicationInteractionID string`

    The interaction ID this span belongs to

  - `ApplicationVariantID string`

    The id of the application variant this span belongs to

  - `CreatedBy Identity`

    The identity that created the entity.

    - `ID string`

    - `Type IdentityType`

      - `const IdentityTypeUser IdentityType = "user"`

      - `const IdentityTypeServiceAccount IdentityType = "service_account"`

    - `Object IdentityObject`

      - `const IdentityObjectIdentity IdentityObject = "identity"`

  - `EndTimestamp Time`

  - `Expected map[string, any]`

  - `GroupID string`

    Reference to a group_id

  - `Input map[string, any]`

  - `InputTokens int64`

    Prompt tokens the producer reported for this span, absent when it reported none. Same quantity the input_tokens sort orders by.

  - `Metadata map[string, any]`

  - `Object SpanObject`

    - `const SpanObjectSpan SpanObject = "span"`

  - `ObsSpanID string`

    W3C span id of the observability span this span executed in.

  - `ObsTraceID string`

    W3C trace id of the observability trace this span executed in. Null for spans written without the edge, and for accounts still served by the legacy trace store.

  - `Output map[string, any]`

  - `OutputTokens int64`

    Completion tokens the producer reported for this span, absent when it reported none. Same quantity the output_tokens sort orders by.

  - `ParentID string`

    Reference to a parent span_id

  - `Status SpanStatus`

    - `const SpanStatusSuccess SpanStatus = "SUCCESS"`

    - `const SpanStatusError SpanStatus = "ERROR"`

    - `const SpanStatusCanceled SpanStatus = "CANCELED"`

  - `Type SpanType`

    - `const SpanTypeTextInput SpanType = "TEXT_INPUT"`

    - `const SpanTypeTextOutput SpanType = "TEXT_OUTPUT"`

    - `const SpanTypeCompletionInput SpanType = "COMPLETION_INPUT"`

    - `const SpanTypeCompletion SpanType = "COMPLETION"`

    - `const SpanTypeKBRetrieval SpanType = "KB_RETRIEVAL"`

    - `const SpanTypeKBInput SpanType = "KB_INPUT"`

    - `const SpanTypeReranking SpanType = "RERANKING"`

    - `const SpanTypeExternalEndpoint SpanType = "EXTERNAL_ENDPOINT"`

    - `const SpanTypePromptEngineering SpanType = "PROMPT_ENGINEERING"`

    - `const SpanTypeDocumentInput SpanType = "DOCUMENT_INPUT"`

    - `const SpanTypeMapReduce SpanType = "MAP_REDUCE"`

    - `const SpanTypeDocumentSearch SpanType = "DOCUMENT_SEARCH"`

    - `const SpanTypeDocumentPrompt SpanType = "DOCUMENT_PROMPT"`

    - `const SpanTypeCustom SpanType = "CUSTOM"`

    - `const SpanTypeCodeExecution SpanType = "CODE_EXECUTION"`

    - `const SpanTypeDataManipulation SpanType = "DATA_MANIPULATION"`

    - `const SpanTypeEvaluation SpanType = "EVALUATION"`

    - `const SpanTypeFileRetrieval SpanType = "FILE_RETRIEVAL"`

    - `const SpanTypeKBAddChunk SpanType = "KB_ADD_CHUNK"`

    - `const SpanTypeKBManagement SpanType = "KB_MANAGEMENT"`

    - `const SpanTypeGuardrail SpanType = "GUARDRAIL"`

    - `const SpanTypeOutputGuardrail SpanType = "OUTPUT_GUARDRAIL"`

    - `const SpanTypeTracer SpanType = "TRACER"`

    - `const SpanTypeAgentTracer SpanType = "AGENT_TRACER"`

    - `const SpanTypeAgentWorkflow SpanType = "AGENT_WORKFLOW"`

    - `const SpanTypeStandalone SpanType = "STANDALONE"`

### Example

```go
package main

import (
  "context"
  "fmt"
  "time"

  "github.com/scaleapi/sgp-dev-go"
  "github.com/scaleapi/sgp-dev-go/option"
)

func main() {
  client := sgpdev.NewClient(
    option.WithAPIKey("My API Key"),
    option.WithAccountID("My Account ID"),
  )
  span, err := client.Spans.New(context.TODO(), sgpdev.SpanNewParams{
    SpanCreate: sgpdev.SpanCreateParam{
      Name: "name",
      StartTimestamp: time.Now(),
      TraceID: "trace_id",
    },
  })
  if err != nil {
    panic(err.Error())
  }
  fmt.Printf("%+v\n", span.ID)
}
```

#### Response

```json
{
  "id": "id",
  "account_id": "account_id",
  "name": "name",
  "start_timestamp": "2019-12-27T18:11:19.117Z",
  "trace_id": "trace_id",
  "application_interaction_id": "application_interaction_id",
  "application_variant_id": "application_variant_id",
  "created_by": {
    "id": "id",
    "type": "user",
    "object": "identity"
  },
  "end_timestamp": "2019-12-27T18:11:19.117Z",
  "expected": {
    "foo": "bar"
  },
  "group_id": "group_id",
  "input": {
    "foo": "bar"
  },
  "input_tokens": 0,
  "metadata": {
    "foo": "bar"
  },
  "object": "span",
  "obs_span_id": "obs_span_id",
  "obs_trace_id": "obs_trace_id",
  "output": {
    "foo": "bar"
  },
  "output_tokens": 0,
  "parent_id": "parent_id",
  "status": "SUCCESS",
  "type": "TEXT_INPUT"
}
```