---
title: "Observability models"
description: "TraceView is the stable typed projection for reading a finalized trace. Its entries preserve whether a value was observed, reported, inferred, redacted, or unavailable."
---

> M3 v0.2.16 · commit 796f6943274f075d973f267794444b91ba208010.


# Observability models

`TraceView` is the stable typed projection for reading a finalized trace. Its
entries preserve whether a value was observed, reported, inferred, redacted,
or unavailable.

Main entry groups:

- Initialization and lifecycle: `InitializationEntry`, `LifecycleEntry`,
  `ProcessEntry`, `RuntimeTraceInfo`, `TraceStatus`, `TraceTiming`.
- Protocol and transport: `ProtocolEntry`, `ProtocolCallAttempt`,
  `ProtocolErrorInfo`, `ProtocolKind`, `TransportEntry`, `HttpExchange`.
- Tools: `ToolCallEntry`, `ToolCallAttempt`, `ToolCallStatus`, `ToolResult`,
  `ReportedToolCall`, `WireToolCall`.
- Messages and model activity: `MessageEntry`, `MessageRole`, `ReasoningEntry`,
  `ProviderEntry`, `UsageEntry`, `UsageValue`.
- Interactions: `InteractionEntry`, `ElicitationEntry`, `WorkspaceEntry`.
- Evidence: `Observation`, `ObservationState`, `ObservationReason`,
  `RawEvidence`, `RawEvidenceSource`, `EvidenceCapture`, `EvidenceConflict`,
  `ArtifactEntry`, `RawMessageEntry`, `SafeHttpHeader`.

Harness-specific projections are `ACPTrace`, `ClaudeCodeTrace`, `CodexTrace`,
`OpenCodeTrace`, and `PiTrace`; `DirectTrace` covers direct MCP work.

`CaptureOptions` configures capture at execution creation. Redaction and missing
provider fields can make raw or normalized evidence unavailable. APIs that
require finalized or raw evidence raise the corresponding documented error
rather than fabricating a value.