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Entities

Entities are a core concept that maps your business entities to telemetry concepts. They enable entity detection, highlighting, message matching, and many features that depend on identifying your AI components. Entities add badges and icons to spans, enable filtering by entity type, surface important fields as highlights on span cards, and extract chat messages for conversations. Learn more about Entities in the core concepts.

Configurations - Entities


Why entities matter

Entities are one of the most important features in Arcane. They enable:

  • Entity detection — Arcane identifies which spans match your business entities
  • Highlighting — Important information (latency, tokens, errors) is highlighted on span cards
  • Message matching — Chat messages are extracted from model spans for readable conversations
  • Entity badges and icons — Spans show entity badges and icons to quickly identify AI components
  • Filtering — Filter traces by entity type to focus on specific components (models, tools, agents)
  • Trace visualization — Entity types help organize and visualize traces
  • Conversation stitching — Entities help identify and group related spans

Many features throughout Arcane depend on entities working correctly. Without entities, traces remain raw telemetry data that's hard to understand and use.


What you see

The Entities tab shows a table of all configured entities:

ColumnDescription
NameThe entity name (e.g., "GPT-4", "Search Tool") used for badges, icons, and filtering
TypeEntity type (Model, Tool, Agent, etc.)
DescriptionOptional description of what this entity represents
Pattern MatchThe matching rule used to identify spans
Created DateWhen the entity was created
ActionsEdit, Delete, and reorder buttons

Quick Start (Start from Source)

If you use a popular instrumentation library, you can import pre-configured entities in one click. Click Start from Source to open a dialog with templates for:

Start from Source dialog

LibraryDescription
OpenInferenceOpenTelemetry-based inference tracing
OpenLLMetryOpenTelemetry LLM observability
OpenLITOpenTelemetry LLM instrumentation
OpenTelemetryOpenTelemetry semantic conventions for traces

Select a library and the entities are imported immediately. You can re-import later to update entities—entities with externalId are updated in place instead of duplicated.


Creating an entity

Click New Entity to create an entity that labels spans. The creation process is a multi-step wizard.

The wizard has four steps:

Step 1: Basic Info

FieldRequiredDescription
Entity TypeYesChoose from: Model, Tool, Agent, Guardrail, Embedding, Retriever, Evaluator, or Custom
NameYesThe entity name used for badges, icons, and filtering (e.g., "GPT-4", "Search Tool")
DescriptionNoOptional description to help your team understand what this entity represents

Step 2: Matching

Define how Arcane identifies spans that should get this label:

  • Attribute name — The span attribute to check (e.g., openinference.span.type)
  • Value or regex — The value to match, or a regex pattern (e.g., MODEL)

Tip: Put more specific rules first. Arcane uses the first matching entity, so order matters.

Step 3: Highlights

Choose which fields appear on span cards when this entity matches. Examples:

  • Latency
  • Token count
  • Error messages
  • Custom attributes

Step 4: Message Matching (Models only)

For Model entities, configure how to extract chat messages from spans. This makes conversations readable in the Trace view and Conversations page.

Buttons: Cancel closes without saving. Next moves to the next step. Create finishes on the last step.


Entity types

TypeUse case
ModelLLM calls (GPT-4, Claude, etc.)
ToolFunction calls, API calls
AgentAgentic workflows
GuardrailSafety checks, content filters
EmbeddingEmbedding model calls
RetrieverRAG retrieval steps
EvaluatorEvaluation steps
CustomAny other AI component

Import and export

  • Export — Download your entity catalog as YAML.
  • Import — Upload a YAML file to restore entities from a backup or copy them to another organization.

Updating entities on re-import (externalId)

Entities with an externalId field are updated when re-imported, rather than duplicated. This lets you:

  • Re-import a Quick Start template to pull in changes or fixes
  • Maintain consistent entity definitions across environments (e.g., staging → prod)
  • Iterate on a YAML file and re-import without creating duplicates

Exported YAML includes externalId when present. For manual imports, add externalId to entities you want to be updatable (e.g. externalId: opentelemetry.chat).

Tip: Export your entities before making major changes, or when setting up a new organization with similar components.


When to use

  • Before browsing traces — Add entities so spans show entity badges, icons, and highlights
  • For models — Configure message matching so conversations are readable
  • Organizing components — Create entities for all your AI components (models, tools, agents)
  • Team clarity — Use clear, consistent names so your team can quickly identify components

Example

Scenario: You want to detect entities defined by the OpenInference instrumentation library. In this case, you want to detect all LLM calls (also called "Models"). You create a Model entity, define the matching rule, configure message detection, and then you can see the messages from the span.

  1. Entity Type: Model
  2. Name: OpenInference Model
  3. Matching: Attribute openinference.span.type, Value MODEL
  4. Message Matching: Configure how to extract chat messages from the span
  5. Result: All matching spans show "OpenInference Model" badge, and chat messages are extracted and visible in the Trace view and Conversations page