[tt-a1i]

Problem

The session usage popover reports total tokens and context occupancy, but does not show how much observed context comes from system text, tool declarations or conversation content. Relates to #913.

Value

Users can inspect the latest observed call's composition while keeping local byte measurements separate from Pi's context estimate and provider-reported token usage.

Approach

Observe Pi's existing context_with_system hook and replay its native system/tool state. Keep one numerical snapshot per Session and project it through existing session usage. Clear it at native context/lifecycle boundaries. No raw prompt archive, extra model call, new tool or configuration is introduced.

Pi context hook -> numerical snapshot -> existing session usage popover

Includes the pinned community investigation and concrete semantic-navigation/diagnostic-delta limitations.

Validation

• bun run check passed with Bun 1.3.14.

• bun run test: Node 2,467 passed, 8 skipped; UI 1,633 passed.

• Additional unskipped observer test passed; native integration verifies unchanged input, replay, later-handler boundary, repeated calls and lifecycle invalidation.

• Actual PiWebRuntime factory + isolated loopback provider exposed 12 normal tools; observation reached /api/snapshot and the browser. Ego visual acceptance passed.

• Independent review corrected an inaccurate Pi 1.2 availability hint. Minimum-host CI remains a separate gate.

• Initial CI stopped before runtime tests on Web bundle freshness. Both worktrees now have independent Bun 1.3.14 frozen installs; rebuilt assets eliminate 33 unrelated chunks. Full check/test passed again under that installation, and corrected-head CI passed.

• Packaged-startup CI then exposed a missing Pi AI root alias. The exact missing-peer pack/install failed before the fix and started/served local assets/exited cleanly afterward. The fix extends the existing selected-host alias map, with no dependency change. Full check/test passed again after this fix.

• Final head e156a220f46dabe979c7536e001c2eb6ca57b004: CI run 42267480520 passed all 19 jobs, including minimum/latest Pi, packaged startup, Windows and both Web E2E shards. The repository still requires an independent GitHub approval.

• Local combined integration of feat(web): show observed context composition in session usage #914 e156a220, feat(web): preserve source identity in review and plan references #915 6e800f83 and feat: add on-demand semantic navigation skill #916 1919dccd: full check/test passed (Node 2,471 pass / 8 existing skips; UI 1,638 pass). The two overlapping generated assets were rebuilt from combined source; no source conflicts. This is separate from individual-head CI and remote merge.

Impact

User-visible: an observed-context section in session usage, with unavailable and omitted-media states.
Model-visible: no additional tools, prompts or calls.
Runtime: one numerical latest-call observation; no raw context retained or persisted.
Configuration/data: unchanged.
Compatibility: helper capability detection; source inspection confirms Pi 0.99.1 support.
Limit: this is the hook's observed context, not final wire content, exact token attribution or billing. Generated Web assets are included.