Review round: the JSONL backend now refuses a foreign header version straight
from the raw header line, before validating today's header shape or decoding
any event row, so a structurally different future format reports the upgrade
direction instead of corruption (shared message builder
sessionFormatVersionRefusal). HMR live-prefix adoption runs the unknown-type
guard like the other read paths. The appendCore comment now states why the
unknown-type guard is read-side only, the loadStoredFrom JSDoc and README pin
the seek-vs-sequential refusal-scope divergence, and the generated catalog
preamble lists the ignorable envelope field.
Old runtimes meeting a newer session format now fail loud instead of
misreading: version refusal names the direction (newer: upgrade the
harness; older: no upgrade path) and points at the raw JSONL log, and an
event type outside the generated known vocabulary refuses resume unless
its envelope carries the new ignorable: true marker (default: required,
so a forgotten marker over-refuses instead of silently resuming a gutted
session). gen-persistence-catalog now also emits
KNOWN_SESSION_EVENT_TYPES; SQLite stores the marker in a dedicated
column (SCHEMA_VERSION 15). The versioning design (monotonic integer,
n->n+1 upgrader chain, migrate-on-continue) is recorded in the
session-log-version-mechanism Agent Note.
Replaces the patch round trip. An app's entrypoint resolves the command
line into a service, and the rows it configures read that service from
their own config — port: !!js ctx.get('webStartup')?.port ?? 3080 — so the
resolved value beats the value written beside it and nothing is written
back into a row or handed to the launcher.
A bundle names the entrypoint row in its manifest (dsh.bundle.entrypoint),
which is what lets the boot mount in two passes: entrypoints alone, then
the whole composition. That ordering is required, not cosmetic — a row's
config expressions are evaluated when the include applies the row, and a
strict ctx.get only answers for a service whose providing fiber is already
active.
What this removes: ctx.appPatches and the launcher-owned patch layer, the
disable/re-enable recycle and its in-flight-mount barrier, overrideConfig,
and the reload hazard they existed for. A live config edit now re-applies
the second pass against services that are still up, so a served port
survives by construction.
What it adds: ctx.appReady, because Loader settlement no longer means the
app is up — a row mounted in the second pass can observe a settled tree
while that pass is still running, or already rolling back. The web URL line
waits for it, so a boot that fails in the second pass announces nothing.
The Agent Note keeps the three vendored-Loader facts the mechanism turns on
— a row's config is resolved and validated when its fiber is created, while
it is still waiting; an inject update loses the plugin's static injections;
a row cannot be inserted from inside a mounting plugin — with the
alternatives they ruled out.
Tool and prompt-section visibility is inherited along dsh-scope's parent
chain, and an agent's scope key is minted with no parent. Per-session agent
presets moved every model-facing row onto the agent plane and made
AgentPresets.mount() the one thing that binds that link, from the api-proxy's
session create, resume, and fork paths. The two in-process subagent drivers
installed only the per-child persona and tool filter, so a child's scope chain
had length one and its registry view resolved the global layer alone — which
is empty wherever a preset roster is composed. One-shot children reached the
model with no tools, continuable ones with only the host-plane `report`, and
neither carried its parent's persona, workspace context, or skill catalog.
AgentPresets.composeFrom() joins one agent to the standing composition another
already runs on. It is a bind, not a mount: the child gets its parent's exact
generation, so a composition edited since the parent started cannot fork it
onto another one, and it is synchronous, which is what lets a child creation
window use it. applyChildComposition() now takes the parent and performs the
join first, making a child composed without it unrepresentable at the call
sites. childSessionMeta() records the joined id so a cold read rebuilds the
composition the child actually ran under.
The audit that followed found two api-proxy readers on the wrong authority:
presenterScopeFor() and the live-agent branch of assertPresetUnchanged() both
read header.agentPreset, which goes stale the moment a blank session switches
preset. A switched session's cold transcript resolved presenters in the older
composition's layer and silently degraded to generic cards, and the gateway
refused to adopt a live session under the preset it actually runs while
accepting the one it left. Both now resolve through resolveSessionPreset(),
matching the resume branch fifteen lines above. The owning architecture Agent
Note carried the stale claim that the header records what a session runs; it
is corrected to name the header/log pair and its three readers.
Fixes#2165
