aiturk-hermes-ide/docs/observability/relay-shared-metrics.md

NeMo Relay Shared Metrics

Hermes includes NeMo Relay as a normal runtime dependency on platforms for which Relay publishes a native wheel. The shared-metrics integration is built into Hermes and does not require a Hermes observability plugin. Hermes remains importable without Relay on other native targets. Those targets use an explicit reduced-capability no-op host: Hermes execution remains available, while Relay scopes, middleware, plugins, and subscribers are unavailable. The hermes-agent[nemo-relay] extra remains as a no-op compatibility alias for existing installation commands.

Warning

This removes the Hermes observability/nemo_relay plugin. Existing users must remove observability/nemo_relay (or its legacy nemo_relay alias) from plugins.enabled and move exporter configuration into a Relay plugins.toml selected with HERMES_NEMO_RELAY_PLUGINS_TOML. The legacy HERMES_NEMO_RELAY_ATOF_* and HERMES_NEMO_RELAY_ATIF_* variables no longer activate exporters. Without the new variable, Hermes does not run Relay plugin discovery, configuration layering, middleware, or exporters.

Hermes requires NeMo Relay 0.8.3 or later within the 0.8 release line. That line provides the provider-codec and canonical tool-result contracts Hermes uses for managed provider and tool calls.

Runtime Dependency and Data Boundary

Hermes installs the platform-specific nemo-relay native wheel from the bounded >=0.8.3,<0.9 dependency range. The published package is built from the NVIDIA NeMo Relay repository. Unsupported platforms use the explicit no-op runtime described above rather than downloading a different implementation.

Operator-supplied typed native plugins must be rebuilt for Relay 0.8. grpc-v1 workers must be regenerated and rebuilt when they use tool callbacks, tool execution intercepts, or manual tool-end APIs.

When Relay managed execution is active, the provider request and response pass through that native module in the Hermes process so configured interceptors can operate on the real call. This is separate from the shared-metrics data contract. Shared-metrics mode installs no rich-observability network exporter, and its subscriber accepts only the versioned, allowlisted projection described below. The opt-in package sender described in Appendix A is the only outbound path, it transmits nothing unless the user enables both enabled and send, and it sends whole packages rather than live spans. Enabling a separately configured rich-observability or dynamic plugin can create a different data path and requires its own policy review.

Collection remains off unless Hermes policy enables it:

telemetry:
  shared_metrics:
    enabled: true

This choice is read from the profile's own config.yaml. A machine-managed configuration overlay cannot enable or disable shared metrics on the profile's behalf.

Relay plugin activation is owned by the native runtime and remains explicitly opt-in. Set HERMES_NEMO_RELAY_PLUGINS_TOML to a selected plugins.toml to activate configured middleware, exporters, or dynamic plugins. When the variable is unset, Hermes does not invoke Relay's plugin initializer, so Relay does not perform plugin configuration discovery or layering. When it is set and the selected file loads successfully, Relay discovers supported user and system plugins.toml files and layers the selected static configuration over them. Repository-local .nemo-relay/plugins.toml files are ignored. Dynamic [[plugins.dynamic]] records are loaded from the selected file only. If the selected file cannot be loaded, Hermes reports the error and does not invoke Relay initialization or fall back to ambient discovery.

Session-Span Segmentation for Continuous Sessions

Relay exports a span when its scope closes. A continuous gateway session can remain open for days, so its session span remains open even though each turn span is exported normally. Optional segmentation rotates only the session scope at a turn boundary:

gateway:
  telemetry:
    session_segments:
      on_compaction: false  # rotate after context compaction
      max_turns: 0          # 0 = unlimited; N = turns per segment

Key	Default	Behavior
on_compaction	false	Rotate after compaction completes, at the next turn boundary.
max_turns	0	Rotate after every N completed turns; 0 disables the cap.

Both defaults preserve one session scope for the full session. Rotated spans retain the same session_id and add hermes.session.segment plus hermes.session.segment_reason (compaction or max_turns).

Process-Wide Plugin Policy and Profile Isolation

Relay plugin configuration is a process-level deployment choice, not a Hermes profile setting. The first hosted profile triggers lazy initialization, and every additional profile hosted by that Hermes process shares the resulting static middleware, dynamic plugins, subscribers, exporters, and guardrail policy. After initialization succeeds, Hermes logs:

Relay plugins are active process-wide and apply to all profiles hosted by this Hermes process.

Profile scopes still preserve causal isolation inside that shared policy. ATIF groups events by their top-level Agent scope, so simultaneous profile sessions produce separate trajectories rather than one mixed trajectory. ATOF and other global subscribers observe events from every hosted profile. Static and dynamic middleware likewise runs for managed calls from every profile.

A worker plugin running in a separate worker process does not create a per-profile security boundary. One process-wide activation dispatches calls from all hosted profiles to that worker while preserving the invoking profile's Relay scope stack. Native dynamic plugins are loaded into the Hermes process and share the same policy boundary.

Run profiles in separate Hermes processes when they require different trust levels, plugin credentials, exporter destinations, or guardrail policies. This process-wide plugin contract does not change each profile's independent shared-metrics consent, local SQLite state, or ATIF trajectory grouping.

Hermes core owns one Relay host and one isolated Relay session scope per Hermes session. Core lifecycle producers use hermes_cli.observability.relay_runtime to obtain the shared session handle or run Relay scope, LLM, tool, and mark APIs in that session context. New product marks do not require Hermes plugin registration. Shared-metrics marks must still contain only fields approved by the versioned allowlist; the hard dependency does not change the collection or privacy policy.

Current Slices

The current vertical slices record pseudonymous profile activity, logical model calls, top-level task runs, tool and approval outcomes, and skill lifecycle and reuse:

Hermes turn, API, tool, and approval hooks
  -> Relay session, task, LLM, tool, and mark lifecycle
  -> Hermes shared-metrics subscriber
  -> SQLite counters
  -> immutable JSON delta package

Hermes sends an empty LLMRequest into the metrics-owned lifecycle. This does not describe the separate managed-execution call through the native runtime documented above. The terminal metrics event contains the model identifier and provider route that Hermes used for the logical call, such as nvidia/nemotron-3-ultra through openrouter. These identifiers are lowercased and structurally bounded, but they are not normalized through a checked-in model catalog. Pricing and model-family classification belong to the metrics backend. Prompts, responses, endpoints, errors, session IDs, task IDs, and request IDs are not included in the metrics event or package. New calls use hermes.model_route.count. The previous hermes.model_call.count contract remains readable only so pending local counters created by older builds can be exported without losing data.

The first consented session start emits an empty hermes.client.active Relay mark. The profile-scoped subscriber creates a random UUID install identity and uses a transactional compare-and-set to record at most one client-active counter in any rolling 24-hour window. The metric has no dimensions; Hermes version, OS family, architecture, and install method remain bounded package resources. Concurrent Hermes processes share the SQLite latch, so simultaneous starts cannot double-count one install. A later session or task can attempt the mark again, but the subscriber suppresses it until the rolling window expires.

Each task run is a Relay Function scope named hermes.task_run, parented to the owning Hermes session. The start counter contains only bounded execution surface and entrypoint values. The terminal counter contains bounded outcome, end reason, termination status, duration, logical model-call count, terminal tool-call count, and provider-retry count buckets. Retries are additional provider attempts for the same Hermes API request ID; they do not inflate the logical model-call count. Tool calls are deduplicated by their Hermes tool-call ID after a terminal tool result is observed. The outer AIAgent execution boundary closes the task for normal returns, early returns, exceptions, and cancellations. Active task ownership follows the task ID if Hermes rotates its conversation session during context compression.

Each tool invocation is represented by a Relay tool lifecycle named hermes.tool_call. The terminal counter contains only bounded tool category, outcome, approval outcome, latency, and explicit retry-count buckets. Hermes derives the category from the toolset already declared in its runtime registry; custom and unrecognized toolsets collapse to other rather than exporting tool or plugin names. Hermes does not infer retries from repeated tool names or adjacent calls; when the hook does not provide an explicit retry relationship, the retry bucket is unknown. Approval decisions are emitted as hermes.tool_approval marks and recorded as attributed to a tool call or explicitly unattributed. Tool names, call IDs, arguments, results, commands, descriptions, and error text are not included in shared-metrics events or packages. A started tool that is still open when its task terminates is closed as failed, timed out, or cancelled and remains in the task's tool-count bucket.

Successful skill mutations emit hermes.skill.lifecycle marks with only a bounded action and provenance. Successful loads emit hermes.skill.load marks with bounded provenance, first-use or reuse state, reuse-after-patch state, and a use-count bucket. Hermes derives reuse and patch-generation continuity transactionally in its existing skills/.usage.json state; skill names and exact counts or generations never enter Relay metrics events, SQLite dimensions, or packages. A use after a new patch is counted once as reused_after_patch; later uses remain ordinary reuse until another patch. Task-outcome attribution after a patch remains deferred until its window and multi-skill semantics are defined.

Local state is written under:

$HERMES_HOME/telemetry/shared_metrics/metrics.sqlite3
$HERMES_HOME/telemetry/shared_metrics/outbox/*.json

The database keeps transactional aggregate and package-outbox state. Package files are immutable delta documents that conform to a closed JSON schema and are written with atomic replacement. Each package records the Hermes version, OS family, architecture, and install method as bounded client resources. Unrecognized platform or installation values are exported as unknown; raw platform strings, hostnames, and paths are never included. Fully packaged aggregate rows and successfully exported package rows and files are retained locally for 30 days. Pending package rows and counters with unexported deltas are never pruned. Package schema v1 remains unchanged for existing outbox files. New packages use v2, which accepts both the retired model-call contract and the current model-route contract so upgrades can drain pending counters safely.

Each package contains an install_id generated as a random UUID. Despite the schema field name, its current scope is one HERMES_HOME, so it is more precisely a persistent pseudonymous profile identifier. It is not derived from hardware, account, host, path, or credential data. It remains stable across packages from that profile and can therefore link those local packages. Deleting $HERMES_HOME/telemetry/shared_metrics resets the identifier together with all aggregates and package files.

Remote delivery is opt-in and off by default. Reusing the persistent local identifier remotely required a separate product and privacy decision covering consent, identity scope, reset behavior, retention, and deletion — that decision has been made.

Those decisions are recorded in Appendix A, and the exporter implementing them has shipped. Collection alone still transmits nothing: the sender runs only when telemetry.shared_metrics.send is also true. Each transmitted package carries the stable install_id as-is (product decision, 2026-08-27 — see A.2 for the record, including the superseded HMAC-pseudonym design).

The install identity is scoped to one HERMES_HOME. To reset it, stop Hermes processes and remove $HERMES_HOME/telemetry/shared_metrics. This deliberately removes the old identity, aggregate database, and queued local packages together; the next consented session creates a new identity. Disabling shared metrics stops new collection but does not silently delete previously collected local state.

Smoke Test

Run a real Hermes CLI turn against the deterministic local model server:

./.venv/bin/python scripts/smoke_nemo_relay_shared_metrics.py

The script uses the installed nemo-relay dependency by default. Pass --relay-python ../nemo-relay/python only when testing a locally built Relay binding.

The smoke has the local model request a real read_file tool call before its final response, then drives create, load, reuse, patch, edit, stale, archive, restore, and install skill transitions through the installed Relay binding. It verifies model, provider, task, tool, and skill counters in SQLite, validates all exported delta packages against the closed schema, verifies the pseudonymous client-active counter, and checks that prompt, response, tool-call ID, tool-result, and skill-name canaries are absent from the packages.

Appendix A: Remote Exporter Decisions (Phase 2)

Status: implemented. This appendix answers the product and privacy questions that "Current Slices" defers to a future remote exporter. It records what was decided and why, so the reasoning survives the implementation.

Sending is off by default and requires both telemetry.shared_metrics.enabled and telemetry.shared_metrics.send.

The exporter sends the package files already written under $HERMES_HOME/telemetry/shared_metrics/outbox/ to the Hermes telemetry ingest service. That service validates only the envelope (schema_version plus a UUID package_id) and stores the body verbatim in S3.

A.1 Consent

Transmission is a separate opt-in from collection, under a new config key:

telemetry:
  shared_metrics:
    enabled: false   # collect locally
    send: false      # NEW: transmit to the Nous telemetry service

• send defaults to false. Collection alone never transmits.
• send requires enabled. It does not imply it: a transmission flag must not silently switch on collection. send: true with enabled: false warns and does nothing.
• Like enabled, send is profile-owned and is not overridden by managed-scope configuration.

A package is only sent when its whole period falls inside a recorded consent window. Consent is stored as explicit intervals in the shared- metrics SQLite store (send_consent_windows): a window opens when send: true is first observed, is confirmed forward by every later observation, and closes — at the last confirmed moment, never at the wall clock — when send: false is observed. A single reconciler derives this table from the config on every process start, so wizard changes, hand-edits to config.yaml, and mid-pass revocations all take the same path, and no transition can be missed by any of them.

Any package whose period predates the first window, falls between windows, or runs past the newest confirmed moment is excluded — the gate fails closed. A fresh package therefore waits at most one process start after its period completes before becoming eligible.

The gate is on the period, not on the package's creation time. One period is split across several packages created on different days: a day's first package is written that day, and a tail package for the same period typically follows the next day. Gating on creation time would send a period's tail while dropping its head, reporting a silently undercounted day. Gating on the period keeps consent forward-only and every transmitted period complete.

Local history can be up to 30 days old, and that data was collected under a promise that nothing is uploaded. Honouring consent forward-only costs at most 30 days of backlog we never had permission to send.

A.2 Identity scope — the stable install_id is transmitted as-is

Decision record. The original design of this exporter (and revisions 1–8 of this appendix) transmitted a keyed pseudonym instead of the identifier: HMAC-SHA256(key = locally-held rotating salt, message = install_id), with the salt rotating every 30 days. On 2026-08-27, before the feature shipped (zero consented users, zero production transmissions), the product owner decided the analytical need is a stable cross-window identity — retention curves, longitudinal install behaviour — which rotation by design destroys. The pseudonymization layer was removed in full rather than weakened in place.

What is transmitted now:

• Each package carries install_id verbatim: the persistent, profile-scoped random UUID described above.
• It is generated locally (uuid4), contains no hardware, account, user, or machine-derived information, and identifies a profile, not a person.
• It is stable until the user deletes the shared-metrics directory, which regenerates it (see A.4).

Consequences stated plainly rather than papered over:

• Packages from one profile correlate indefinitely, not per-window. Long-term linkability of one install's daily envelope sequence is now the designed behaviour, not a residue.
• The A.3 residue analysis of the old design (stable resource tuple + contiguous periods bridging rotation windows) is moot — there is no window boundary left to bridge.
• The setup wizard's consent language states this identity model explicitly; it was updated in the same change that removed the derivation, so no consent was ever collected under the old wording in any shipped build.

Byte-identical resends still hold. The transmitted id is recorded on the row (sent_install_id) when the package is first prepared, and the wire body is always rebuilt from that recorded value, so a retry rebuilds identical bytes. The contract requires this: resending a package_id with different content is undefined behaviour. (With a stable id the recorded copy is no longer load-bearing against rotation — it remains as the audit column and as cheap insurance against any future change to identity semantics.)

A.3 Rotation — removed (decision record)

Salt rotation was deleted together with the derivation (product decision, 2026-08-27). This section is retained as a record of what the earlier design did and why the removal was accepted:

• Rotation existed to bound long-term linkability: one identity per 30-day window, unrelated identities across windows.
• The documented residue (see git history for the full analysis): the envelope's stable, low-entropy resource tuple plus contiguous daily periods could plausibly bridge windows for rare configurations anyway, so the boundary was a cost-raiser, not a wall.
• The product need that killed it: cross-window continuity is precisely what retention analysis requires. A boundary that mostly inconveniences honest analysis while only raising costs for a determined correlator was judged the wrong trade once stable identity became a requirement.

There is no salt in the store, no rotation schedule, and no derived identifier anywhere in the pipeline.

A.4 Reset behavior

Removing $HERMES_HOME/telemetry/shared_metrics still resets local identity, aggregates, and package files, exactly as documented above. Two honest qualifications now apply:

• Reset regenerates install_id, so subsequent packages transmit a new identity. Local reset does give a new remote identity.
• Reset cannot unsend. Packages already transmitted remain in the ingest service's storage under the identifier they were sent with. There is no read-back or delete API in the v1 contract.

Setting send: false stops transmission immediately: consent is re-read before every package, so a pass already in flight stops after the package it is currently sending rather than draining its whole batch. It does not delete previously transmitted packages, and it does not stop local collection.

Turning sending off also closes the consent window — at the last moment consent was actually observed, not at the wall clock. Packages whose periods fall between one window and the next are never transmitted, even if sending is later re-enabled, and this holds for any number of on/off cycles, across hand-edits with no process running, and under a clock that jumps in either direction (window opens are clamped above every timestamp already in the store; observation marks advance by a bounded step per call, so one glitched forward sample cannot drag the confirmation horizon years ahead; a close never lands after the closing observation's own clock). Unlike the earlier single moving opt-in date, closing and reopening does NOT discard the still-undelivered backlog from a previous consented window — those packages stay inside their own interval and remain eligible.

One deliberate upgrade-path consequence: packages exported under the pre-interval consent model (before send_consent_windows existed) predate the first recorded window and are therefore never transmitted after an upgrade. This is the fail-closed direction — re-importing the old moving day-stamp to release them would re-import the semantics five review rounds showed to be unsound — and it costs at most the undelivered backlog, never collected data.

A.5 Retention

• Local: unchanged — 30 days for successfully exported history, and pending deltas are kept until exported. Send state does not extend local retention: a package that could never be sent is still pruned at 30 days. Unbounded local growth against a permanently unreachable endpoint is a worse failure than losing metrics from an install that has been broken for a month.
• Remote: raw packages are retained in S3 without expiry in production and for 30 days in staging.

A.6 Deletion

There is no remote deletion path in the v1 contract, and this appendix does not invent one. What a user can do:

Action	Effect
send: false	No further packages leave the machine
enabled: false	Collection stops; existing local state remains
Remove .../shared_metrics	Local identity, aggregates, and files reset; future sends use a new install_id
Delete already-sent data	Not self-service — requires an operator acting on the S3 bucket

If a deletion-on-request obligation is ever taken on, the lookup path is now direct: the user's install_id (readable from their local store) is the key their data is stored under. Building the service-side delete API remains a new product decision, not an implementation detail.

A.7 What the outbox directory is

Recorded because it was misread once during Phase 2 planning, in a way that would have deleted user data.

The directory is local history, not a send-queue. package_outbox is the SQLite table; its exported_at column means "written to disk", not "sent". Files are immutable and pruned by age alone.

The ingest contract says senders should delete a package from their outbox on 202. The exporter does not do this. Deleting on acknowledgement would repurpose the user's 30-day local history as a transmission queue and destroy state they were promised. Send state lives in new columns on the package_outbox table instead; the files are untouched by transmission.

A.8 Scope note

The install_id field inside the package body is transmitted as the generator wrote it (rewritten from the row's frozen sent_install_id, which records the same value). No other payload field changes, nothing is added, and the service treats the whole body as opaque. Payload schema evolution therefore stays a sender-side concern, as before.