> ## Documentation Index > Fetch the complete documentation index at: https://docs.langchain.com/llms.txt > Use this file to discover all available pages before exploring further. # Run (span) data format LangSmith stores each [run](/langsmith/observability-concepts) as a structured record. Understanding this format is useful when exporting traces, querying the API, or building integrations. | Field Name | Type | Description | | ------------------------------ | ---------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | | **`id`** | UUID | Unique identifier for the span. | | **`name`** | string | The name associated with the run. | | **`inputs`** | object | A map of inputs provided to the run. For runs with `run_type='llm'`, this typically contains a `messages` array of message objects sent to the model. | | **`run_type`** | string | [Type of run](#run-types), for example, `'llm'`, `'chain'`, `'tool'`. | | **`start_time`** | datetime | Start time of the run. | | **`end_time`** | datetime | End time of the run. | | **`extra`** | object | Any extra information run. | | **`error`** | string | Error message if the run encountered an error. | | **`outputs`** | object | A map of outputs generated by the run. For runs with `run_type='llm'`, this typically contains a `messages` array of message objects returned by the model. | | **`events`** | array of objects | A list of event objects associated with the run. This is relevant for runs executed with streaming. | | **`tags`** | array of strings | Tags or labels associated with the run. | | **`trace_id`** | UUID | Unique identifier for the trace the run is a part of. This is also the `id` field of the root run of the trace | | **`dotted_order`** | string | [Ordering string](#what-is-dotted_order), hierarchical. Format: `Z`.`Z`... | | **`status`** | string | Current status of the run execution, e.g., `'error'`, `'pending'`, `'success'` | | **`child_run_ids`** | array of UUIDs | List of IDs for all child runs. | | **`direct_child_run_ids`** | array of UUIDs | List of IDs for direct children of this run. | | **`parent_run_ids`** | array of UUIDs | List of IDs for all parent runs. | | **`feedback_stats`** | object | Aggregations of feedback statistics for this run | | **`reference_example_id`** | UUID | ID of a reference example associated with the run. This is usually only present for evaluation runs. | | **`total_tokens`** | integer | Total number of tokens processed by the run. | | **`prompt_tokens`** | integer | Number of tokens in the prompt of the run. | | **`completion_tokens`** | integer | Number of tokens in the completion of the run. | | **`total_cost`** | decimal | Total cost associated with processing the run. | | **`prompt_cost`** | decimal | Cost associated with the prompt part of the run. | | **`completion_cost`** | decimal | Cost associated with the completion of the run. | | **`first_token_time`** | datetime | Time when the first token of a model output was generated. Only applies for runs with `run_type="llm"` and streaming enabled. | | **`session_id`** | string | Session identifier for the run, also known as the tracing project ID. | | **`in_dataset`** | boolean | Indicates whether the run is included in a dataset. | | **`parent_run_id`** | UUID | Unique identifier of the parent run. | | `execution_order` (deprecated) | integer | The order in which this run was executed within the trace. | | `serialized` | object | Serialized state of the object executing the run if applicable. | | `manifest_id` (deprecated) | UUID | Identifier for a manifest associated with the span. | | `manifest_s3_id` | UUID | S3 identifier for the manifest. | | `inputs_s3_urls` | object | S3 URLs for the inputs. | | `outputs_s3_urls` | object | S3 URLs for the outputs. | | `price_model_id` | UUID | Identifier for the pricing model applied to the run. | | `app_path` | string | Application (UI) path for this run. | | `last_queued_at` | datetime | Last time the span was queued. | | `share_token` | string | Token for sharing access to the run's data. | Here is an example of a JSON representation of a run in the above format: ```json theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}} { "id": "497f6eca-6276-4993-bfeb-53cbbbba6f08", "name": "string", "inputs": {}, "run_type": "llm", "start_time": "2024-04-29T00:49:12.090000", "end_time": "2024-04-29T00:49:12.459000", "extra": {}, "error": "string", "execution_order": 1, "serialized": {}, "outputs": {}, "parent_run_id": "f8faf8c1-9778-49a4-9004-628cdb0047e5", "manifest_id": "82825e8e-31fc-47d5-83ce-cd926068341e", "manifest_s3_id": "0454f93b-7eb6-4b9d-a203-f1261e686840", "events": [{}], "tags": ["foo"], "inputs_s3_urls": {}, "outputs_s3_urls": {}, "trace_id": "df570c03-5a03-4cea-8df0-c162d05127ac", "dotted_order": "20240429T004912090000Z497f6eca-6276-4993-bfeb-53cbbbba6f08", "status": "string", "child_run_ids": ["497f6eca-6276-4993-bfeb-53cbbbba6f08"], "direct_child_run_ids": ["497f6eca-6276-4993-bfeb-53cbbbba6f08"], "parent_run_ids": ["f8faf8c1-9778-49a4-9004-628cdb0047e5"], "feedback_stats": { "correctness": { "n": 1, "avg": 1.0 } }, "reference_example_id": "9fb06aaa-105f-4c87-845f-47d62ffd7ee6", "total_tokens": 0, "prompt_tokens": 0, "completion_tokens": 0, "total_cost": 0.0, "prompt_cost": 0.0, "completion_cost": 0.0, "price_model_id": "0b5d9575-bec3-4256-b43a-05893b8b8440", "first_token_time": null, "session_id": "1ffd059c-17ea-40a8-8aef-70fd0307db82", "app_path": "string", "last_queued_at": null, "in_dataset": true, "share_token": "d0430ac3-04a1-4e32-a7ea-57776ad22c1c" } ``` ## Run types The `run_type` field identifies the kind of operation a span represents. LangSmith uses it to apply appropriate rendering in the trace UI and to enable type-specific features. | Run type | Description | | ----------- | ---------------------------------------------------------------------------------------------------------- | | `chain` | A sequence or composition of steps. | | `llm` | A call to a language model. | | `embedding` | Embedding API calls. (Displays with the `chain` icon in the UI.) | | `prompt` | A [prompt template](/langsmith/prompt-template-format) that formats inputs before passing them to a model. | | `tool` | A function or external action invoked by the model. | | `retriever` | A lookup that fetches relevant documents or context. | | `parser` | An output parser that transforms raw model output into a structured format. | Set [`run_type`](https://reference.langchain.com/python/langsmith/schemas/RunBase/run_type) when instrumenting with [`@traceable`](/langsmith/annotate-code#use-%40traceable-%2F-traceable) or [`RunTree`](/langsmith/annotate-code#use-the-runtree-api): ```python Python theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}} from langsmith import traceable @traceable(run_type="tool") def my_tool(query: str) -> str: ... ``` ```typescript TypeScript theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}} import { traceable } from "langsmith/traceable"; const myTool = traceable( async (query: string): Promise => { // ... }, { run_type: "tool" } ); ``` Some run types have specialized trace views in the LangSmith UI: * [Log LLM calls](/langsmith/log-llm-trace) * [Log retriever traces](/langsmith/log-retriever-trace) ## What is `dotted_order`? A run's dotted order is a sortable key that fully specifies its location within the tracing hierarchy. Take the following example: ```python theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}} import langsmith as ls @ls.traceable def grandchild(): p("grandchild") @ls.traceable def child(): grandchild() @ls.traceable def parent(): child() ``` If you print out the IDs at each stage, you may get the following: ```python theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}} parent run_id=0e01bf50-474d-4536-810f-67d3ee7ea3e7 trace_id=0e01bf50-474d-4536-810f-67d3ee7ea3e7 parent_run_id=null dotted_order=20240919T171648521691Z0e01bf50-474d-4536-810f-67d3ee7ea3e7 child run_id=a8024e23-5b82-47fd-970e-f6a5ba3f5097 trace_id=0e01bf50-474d-4536-810f-67d3ee7ea3e7 parent_run_id=0e01bf50-474d-4536-810f-67d3ee7ea3e7 dotted_order=20240919T171648521691Z0e01bf50-474d-4536-810f-67d3ee7ea3e7.20240919T171648523407Za8024e23-5b82-47fd-970e-f6a5ba3f5097 grandchild run_id=0ec6b845-18b9-4aa1-8f1b-6ba3f9fdefd6 trace_id=0e01bf50-474d-4536-810f-67d3ee7ea3e7 parent_run_id=a8024e23-5b82-47fd-970e-f6a5ba3f5097 dotted_order=20240919T171648521691Z0e01bf50-474d-4536-810f-67d3ee7ea3e7.20240919T171648523407Za8024e23-5b82-47fd-970e-f6a5ba3f5097.20240919T171648523563Z0ec6b845-18b9-4aa1-8f1b-6ba3f9fdefd6 ``` Note a few invariants: * The `id` is equal to the last 36 characters of the dotted order (the suffix after the final `'Z'`). See `0ec6b845-18b9-4aa1-8f1b-6ba3f9fdefd6` for example in the grandchild. * The `trace_id` is equal to the first UUID in the dotted order (i.e., `dotted_order.split('.')[0].split('Z')[1]`) * If `parent_run_id` exists, it is the penultimate UUID in the dotted order. See `a8024e23-5b82-47fd-970e-f6a5ba3f5097` in the grandchild, for an example. * If you split the `dotted_order` on the dots, each segment is formatted as (`Z`) ***
[Connect these docs](/use-these-docs) to Claude, VSCode, and more via MCP for real-time answers. [Edit this page on GitHub](https://github.com/langchain-ai/docs/edit/main/src/langsmith/run-data-format.mdx) or [file an issue](https://github.com/langchain-ai/docs/issues/new/choose).