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# Trait Observability Host

> Runtime operations used by the built-in exporters.

Generated from `cargo doc --no-deps -p nemo-relay-builtins -p nemo-relay-diagnostics -p nemo-relay-logging -p nemo-relay-plugin-host -p nemo-relay-codecs -p nemo-relay -p nemo-relay-runtime -p nemo-relay-model-pricing -p nemo-relay-resource-metrics -p nemo-relay-observability -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

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Runtime operations used by the built-in exporters.

## Required Methods

#### `pricing_snapshot`

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Capture the selected estimator for one projection operation. Detached exporters use the standalone catalog; runtime adapters override this with the embedding application's selected pricing service.

#### `register_subscriber`

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Register an exporter callback.

#### `deregister_subscriber`

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Remove an exporter callback.

#### `flush_subscribers`

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Establish the runtime's subscriber-delivery barrier.

#### `w3c_span_context`

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Parse remote W3C propagation context using the runtime's policy.

#### `record_runtime_diagnostic`

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Mirror an exporter diagnostic into the active plugin session.

#### `set_full_payloads_enabled`

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Configure whether active scopes retain full observability payloads.

#### `try_scope_register_subscriber`

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Register a subscriber on an open scope without emitting lookup diagnostics.

#### `try_scope_deregister_subscriber`

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Remove a scoped subscriber without emitting lookup diagnostics.

#### `scope_deregister_subscriber`

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Remove a scoped subscriber with ordinary runtime lookup behavior.

#### `is_trajectory_parent`

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Whether a scope's parent is the active root or a propagated parent.

#### `record_plugin_diagnostic`

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Record an ATIF diagnostic, retaining its session correlation.

## Implementors

### `impl ObservabilityHost for DetachedHost`

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