surface.replaceGeneration gets its direct-access test (the getter folds
a pending delta itself, not only via a nodes read); the reconstruction
theorem drives maxTokens and stop through the config waterfall; the
compact-basic envelope drops a dead conditional — config.maxTokens is
required and validated positive, so this backend's envelope always
carries the cap (the return type's optionality exists for overriding
subclasses).
The reconstructability RFC is the principle's home: model-visible ⟺
logged in both forms, the mechanism (boundary derivation + header
fold), the enforcement (write-time round-trip guard, the dev
invariant), the corollaries ranked (prefix-cache stability first), the
MiniCode lineage with the provenance arrow inverted, and the
alternatives it beat — including the stateful transmission client
whose three-design archaeology lives in PR #162.
Placements per the one-home-per-fact taxonomy: a standing-order line in
root AGENTS.md (with displacement trims to stay inside the 1,575-word
ceiling), the principle statement in architecture.md § Session Log and
its Turn Flow lines (condensed to the ratcheted 1,630 ceiling), the
request-envelope section in core-data-structures/core.md with the
LlmCallConfig paste, both review-requested FIXMEs
(FIXME(call-config-shape) beside the type, FIXME(catalog-verbs) at the
catalog's drift-gate note), cookbook rows redirected off agent/request
(tool filtering → system-prompt/assemble, plan-mode prompt → sections/
inject()), and the llm/stream JSDoc stating the frozen-request
contract. RFC index and all generated catalogs regenerated.
One re-record after the header events landed: recorded scenarios
re-harvested against the live API; the three fs-writing fixtures are
relativized (this recording's model happened to emit absolute
file_path arguments, which only round-trip through replay when the
path is cwd-independent) and, with the two never-re-recorded authored
scenarios (error-finish, cancel), rewritten in the normalized
authored-fixture form the harness documents — each now carrying the
request/header snapshot the loop logs before its first dispatch.
Keyless replay verified green across all 35 scenarios.
compact/summary gains { model, maxTokens? } — the envelope the
summarize call actually used, reported by the backend that made the
call: summarize() now returns { summary, model, maxTokens? } instead of
bare blocks, so an overriding backend (template or remote summarizer)
reports its own envelope honestly and compactRegion logs it. 'Which
model wrote this summary' becomes answerable from the log alone, and
the one-shot summarize request — outside the loop's header-event fold
by design — is reconstructable from log + code (the reconstructability
RFC's scope statement).
The dev-mode cross-check on llm/stream: a frozen request with a live
sessionId (the loop-built marker; hand-built one-shots stay unfrozen
and skipped) must carry messages deep-equal to the derivation over the
log prefix strictly before the in-flight step's step/start, and header
fields equal to the fold of the log's request/header* events. The
messages side rebuilds through a FRESH Session over the boundary
prefix — same projection code, zero shared state — so the live cache
cannot vouch for itself, and the seq-bounded rebuild is boundary-
correct: content appended after step/start (an agent/request-window
inject) legitimately belongs to the next request and cannot false-fire
the check. prepend:true only defends against the replay adapter's
short-circuit (append-registered); correctness never rests on listener
ordering. There is no divergence-allowance caveat: nothing can shape
request content outside the log.
The loop is now transmission-stateless; a request is a pure function of
(session log, this step's rendered assembly, current AgentOptions):
- The reconstruction boundary is step/start: the messages snapshot is
taken in the same synchronous frame immediately before the step/start
append, so the request's messages are exactly the derivation over
events[0..stepStartSeq) — an inject() from an agent/request listener
(or any concurrent task) lands after the boundary and joins the NEXT
request. This changes behavior for a synchronous step/start
session/event listener that appends content (master derived after the
append, so such a listener could reach the current request):
agent/pre-step is the sanctioned seam for current-request content.
- agent/request is re-typed to config-only: (agent, turn, step,
config: LlmCallConfig, next) → LlmCallConfig. The frozen seed comes
from AgentOptions on a loop instance's first request (explicit options
beat the logged baseline — fork overrides and resume reconfiguration
stay correct) and from the log's folded header afterwards; listeners
return a replacement to switch. Content shaping through the request is
no longer expressible — model-visible content flows through the log
channels.
- recordRequestHeader appends whatever header event the request owes the
log before dispatch: an 'initial'/'resume' snapshot anchoring each
loop instance, a round-trip-verified delta on change, a 'fallback'
snapshot when the encoding cannot express it. Session.requestHeader()
is the log's incrementally-folded baseline.
- Requests are deep-frozen before dispatch (deepFreeze exempts the
AbortSignal — freezing one breaks AbortController.abort() outright);
frozen + sessionId is the loop-built marker the dev invariant keys on.
Ported from #162 and re-anchored on the log: the append-extension /
frozen-end-to-end / compaction-resend / prompt-change property tests,
plus new specs for the boundary semantics, resume anchoring, and the
end-to-end theorem (every recorded request rebuilds byte-equal from the
log alone). Live cache-hit e2e (request-cache.e2e.ts) verified against
the real DeepSeek API. Snapshot goldens intentionally stale until the
single re-record after the compact/summary envelope lands.
deriveMessages() no longer re-derives and re-clones the whole surface
per call: each node is projected exactly once, when first seen (O(new
nodes) per access), through the now-public deriveEventMessage — the
per-node pure function external reconstructors and the dev invariant
fold over a log prefix, so no two paths can disagree about a request's
messages. A surface rewrite (replace, invalidate) rebuilds, signalled
by SurfaceManager.replaceGeneration — monotonic, bumped by every folded
replace and by invalidate(), never reset. Callers get a fresh array
snapshot per call over SHARED deep-frozen messages: isolation of the
append-only log moves from per-call cloning to unrepresentability
(mutation throws), which the two isolation tests now pin directly.
Every conversation request's non-content half (system prompt, tool
schemas, call config — the EpochHeader) is now recorded in the session
log: a 'request/header' full snapshot (reason 'initial' | 'resume' |
'fallback') anchors the fold at conversation birth and process
boundaries, and 'request/header-delta' events (system line-trim,
name-keyed tools delta, whole config) encode mid-run changes. The pure
trio — foldRequestHeader / diffHeader / applyHeaderDelta — reconstructs
the header any request was built under from the log alone; the writer
contract round-trip-verifies every delta with a 'fallback' snapshot
when the encoding cannot express a change (pure tool reordering), so a
well-formed log always folds cleanly. Canonical absence: empty system
and empty tools normalize to absent fields, matching request builds.
Persistence and cordis catalogs regenerated; SessionEventMap paste and
EpochHeader added to the core-data-structures session page.
The call configuration (model + sampling scalars) becomes named
vocabulary: per-conversation state that the session log records as part
of the request header (the reconstructability RFC on this branch), with
callConfigEquals as the real-change detector behind logged header deltas
and deepFreeze as the ownership helper the loop applies to every built
request. dsh-llm stays stateless — request in, chunks out; no
conversation object lives here.
The summarization request no longer dispatches agent/request — that seam
shapes the loop's conversation requests; a hand-built one-shot's
interception surface is llm/stream, like every other direct call. The
model comes from summarizationModel falling back to the agent's own. The
turn/step parameters existed on the compact seam only to feed the
agent/request dispatch and leave compactIfNeeded/compactRegion.
Groundwork for making every conversation request a pure function of the
session log (reconstructability RFC, this branch): the seam split keeps
the loop's request path as the single thing the log must explain.
Ported from worktree-prompt-prefix-stability (PR #162) where it was
review-converged; catalog and producer/consumer graphs regenerated.
Verified against gh: --base filters server-side and exactly, so any
open dependent guarantees a non-zero print, but --jq length counts the
fetched page and gh's default --limit is 30 (--limit 5 prints 5 when
the true count is 20). The printed number is min(actual, limit), so the
skill no longer claims it as the auto-close count; only 0 clears a
delete.
Review comment on the verify step: dumping every open PR under
--limit 1000 wastes agent context and re-truncates past 1000. Ask the
exact question server-side instead: gh pr list --state open
--base <branch> --json number --jq length, whose output is a single
count that is exact at any number of open PRs. Skill, checklist, and
the cookbook dependent-check line all use the per-branch form.
Second review round: 'gh pr merge' can return after merely enabling
auto-merge when required checks are pending or a merge queue is active,
so retargeting the next PR could run against a master that does not yet
contain the parent. The procedure and checklist now require
'gh pr view <n> --json state' to report MERGED after every merge.
Codex review caught three procedure defects: the dependent check used
bare 'gh pr list', whose default pagination can hide an open dependent
and make branch deletion look safe (now --state open --limit 1000); the
refresh step merged local master, which 'gh pr merge' leaves stale (now
fetch and merge origin/master); and the quick checklist omitted pushing
the dependent after the local merge.
Commit the stacked-PR landing procedure as a repo skill so every
collaborator's agent discovers it: merge bottom-up, retarget and refresh
each dependent, and delete no branch until the whole stack has landed
(deleting a base branch auto-closes the open PR that bases on it).
The responding-to-pr-review-on-a-stack cookbook guide's dependent-check
step links the skill as the full landing procedure.
ds-review-bot round 2, both warnings:
- subagent/provider-removed now routes through emitLifecycle (per-listener
containment, the subagent/start|end precedent) instead of raw ctx.emit,
whose dispatch halts on the first throw: a throwing subscriber can no
longer starve a later mirror into keeping a stale tool, nor disrupt the
backend fiber's teardown mid-disposer. provider-added deliberately keeps
propagation (register-time rollback semantics, like the system-prompt
registries); the asymmetry is documented on emitLifecycle, the event
JSDoc, and the provider-lifecycle RFC.
- The documented model-via-agent/request fallback composes with a
{{model}} persona via the ownership rule itself: the plugin supplying
the model late states it early on the system-prompt/assemble waterfall.
Declined re-ordering render after agent/request — it would break the
agent/pre-step contract (compaction must measure the prompt the model
sees). New loop test pins the supply path end-to-end; the RFC's
{{model}} consequence bullet now covers supply as well as switch.
This branch's two RFCs (prompt-variables, provider-lifecycle events)
conform to the new contract in the same merge: 'Status: implemented'
dateless header, 'Rejected alternatives' -> 'Alternatives considered',
'What we give up' folded into '## Consequences' (per the uniform-format
RFC's own rejection of a costs-only closer), and the index regenerated
into the new INDEX.md. docs/rfc/README.md resolved to master's rewrite.
