---
title: "Get Agent Trace Span"
method: GET
path: "/v1/traces/{trace_id}/spans/{span_id}"
tags: ["agent tracing"]
---

# Get Agent Trace Span

`GET /v1/traces/{trace_id}/spans/{span_id}`

## Request

- Base URL: `https://api.sea-lion.ai` (the document declares no server; this is the origin it was published from)
- URL: `https://api.sea-lion.ai/v1/traces/{trace_id}/spans/{span_id}`
- Auth: API key in header `x-litellm-api-key`

## Path parameters

- `trace_id` string, required
- `span_id` string, required

## Query parameters

- `trace_ref` string

## Response `200`

Successful Response

- SpanDetail
  - `span_id` string, required
  - `input_ui` union, required
    - UIMessages
      - `messages` UIMessage[], required
        - `role` 'system' | 'user' | 'assistant' | 'tool', required
        - `content` string, required
        - `name` string, nullable
        - `tool_calls` UIToolCall[]
          - `name` string, required
          - `arguments` string, required
      - `kind` 'messages', required
    - UIFields
      - `fields` UIField[], required
        - `key` string, required
        - `value` string, required
      - `kind` 'fields', required
    - UIText
      - `text` string, required
      - `kind` 'text', required
  - `output_ui` union, required
    - UIMessages
      - `messages` UIMessage[], required
        - `role` 'system' | 'user' | 'assistant' | 'tool', required
        - `content` string, required
        - `name` string, nullable
        - `tool_calls` UIToolCall[]
          - `name` string, required
          - `arguments` string, required
      - `kind` 'messages', required
    - UIFields
      - `fields` UIField[], required
        - `key` string, required
        - `value` string, required
      - `kind` 'fields', required
    - UIText
      - `text` string, required
      - `kind` 'text', required
  - `input` string, required
  - `output` string, required
  - `attributes` object, required

## Other responses

- `422`: Validation Error

## Changes

- **2026-10-21** `f2fb14eab3f5`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/sea-lion/apis/litellm-api/changes/v1/traces/:trace_id/spans/:span_id/get.md)

---

[API](https://skmtc.dev/sea-lion/apis/litellm-api.md) · [All operations](https://skmtc.dev/sea-lion/apis/litellm-api/llms.txt) · [OpenAPI document](https://skmtc.dev/sea-lion/apis/litellm-api/revisions/1ba9123c189a?raw)