Render reconstructable system prompts at each request-series boundary, preserve series declarations through pre-step wrappers, and keep the presentation and replay snapshots aligned across clients.
Add the activity capability seam: ctx.activities is a pure observation
plane where long-running work (background bash/pwsh, workflow runs) opens a
handle, appends transient output into a byte-offset ring buffer, and settles
exactly once. Nothing model-visible changes: reads are non-consuming and
lossy-by-design (absolute UTF-8 offsets survive eviction and report gaps),
correlation carries {callId, jobId}, and visibility is owner-fenced like jobs.
The seam is strictly optional. Producers tap it through ctx.get('activities')
and contain every observation failure, so an unregistered or broken registry
never affects the underlying job (proven by broken-registry tests).
Ship the full path in one change:
- @deepseek-ai/dsh-activity: Service Definition, pumpActivityOutput pull
substrate, invariant companion; dsh-activity-local: ring-buffer provider
with retention config and owner cleanup.
- shell: ShellProcess.observed exposes non-consuming stdout/stderr readers;
tool-bash/tool-pwsh mirror background jobs into activities.
- tool-workflow: phase/log/agent lines mirrored as a workflow activity.
- api-activity-controller: Typert Remote control (roster baseline+buckets)
and observe (opened/output/status frames, coalesced and byte-capped)
streams plus the client feed service with reference-counted observation.
- ui-activity: session-header action rendering live output through
TerminalBlock, which now shows output while a command is still running.
Docs: activity subsystem page, architecture row, regenerated catalogs, and
the Agent Note (2026-08-24-activity-observation-seam), all bilingual. A
keyless web e2e replays a real run_in_background stream to ARIA goldens.
Master dimensions move from a 2048 long-edge rule to a total-pixel
budget (normalizedImageMaxPixels, default 2048x2048) with an 8192
long-edge cap, so extreme aspect ratios keep short-edge resolution.
The shared quality ladder and lazy execution move to encoding.ts,
review-round doc fixes land across attachment and llm packages, and
the superseded facts in the unified-image-pipeline note now describe
the shipped routing.
Delete the 5-bit colour-count classifier and palette PNG branch that
misrouted high-frequency photographic JPEGs (issue #2885 images 23/24)
into an encoder 100x slower with 4x larger output. Both normalization
and request-image encoding now route by the decoded alpha fact alone:
opaque sources down a JPEG ladder and alpha sources down a WebP
effort-0 ladder, each at qualities 85/75/60. Byte budgets become ladder
targets: the downscale retry loop is gone and a ladder-exhausted encode
keeps its smallest output, while provider byte caps stay enforced at
the transmitting route. Request transforms move to request-image-v5.
Yichen Jiang