The proposal survives contact with the code with three amendments, per
the RFCs-are-proposals rule. (1) A mode transition logs a
request/header-delta only when expressible: adding exit_plan_mode
resorts the canonical tool list, and a pure reordering has no delta
form, so entering plan mode logs the full fallback snapshot — the
attributability claim holds either way. (2) The proposed/ skeleton
converts to the implemented grammar: Proposal → Decision, the roadmap's
staging (now history) drops to the standing Deferred list, and
Acceptance criteria + Risks fold into Consequences (what holds, then the
accepted costs, including the ACP v2 mode-removal migration). (3) The
two recorded scenarios stay pending a with-key session, recorded in
Deferred.
The docs tail completes: the cookbook's plan-mode row upgrades from
sketch to the shipped package, architecture.md gains the ctx.modes
capability row (ceiling 1640 → 1650: a new capability service's table
row does not fit the old budget), and every reference repoints to
implemented/.
The design record for tool-cordis: the three-tool contract, the vm sandbox
trust stance and boundary mechanisms, the dynamic-group lifecycle, cross-mount
provide/inject composition, the generated runtime API catalog, and the
alternatives weighed (per-capability registration tools, hand-maintained API
tables, a mount provenance event, a hardened sandbox).
The seam shipped without its own RFC — the reconstructable-requests RFC
was amended with the mechanics, but the decision record (why a
compose-once frozen prefix, and what the per-request before/after shape,
a system-prompt section, a durable history opener, per-turn composition,
and a dedicated session event each lost to) had no home. Implemented
lifecycle, feature class, dated to the first commit of the work.
Brings in the refreshed base (master merged through the stack after #203
and #205 landed), including the acp-snapshot extraction (#204), and
re-ports this PR's snapshot-suite extensions onto the extracted package:
- dsh-acp-snapshot's Scenario gains headerClass and configPath; the suite
factory pins the request header PER CLASS (construction rejects a
missing or duplicated class pin), forwards a scenario's configPath to
the harness (RunOptions.configPath overrides AgentUnderTest.configPath),
and a new fixtures meta-test asserts every pinning fixture carries
exactly one request/header and no deltas.
- The acp-agent example's thin scenario table re-registers code-mode-turn
and both-mode-turn with their overlay configs and per-class pins; the
committed fixtures replay unchanged.
- The package's synthetic suites cover the new surface (explicit
headerClass on one suite, the default on the other, a configPath
override through the fake bin, and the two construction throws).
The dsh-tools half of the Code Mode RFC (its fourth, final change): the
registry gains its first config — mode: native | code | both — and OWNS how
its tools reach the model. 'code' contributes exactly one wire tool,
run_code, plus a lazy tools:sdk prompt section declaring every other tool
as a generated TypeScript API (jsonSchemaToTs: total over the defineTool
subset, unknown degradation, lexicographic byte-identical rendering);
'both' ships both representations; 'native' is byte-for-byte the old
behavior. Non-native modes fail every assembly loudly without a
typescript-language ctx.codeRuntime.
run_code's dispatch bridge: JSON-normalizes each binding argument before
dispatch (what dispatches is what the tool/code-dispatch event logs — the
append can never fail on payload shape; BigInt/circulars reject that one
call), serializes all program tool calls through a per-run queue (even
Promise.all — no concurrency-safety metadata yet), routes every sub-call
through tools/pre-execute → tools/post-execute (a deny rejects the
program-side promise), drops sub-call additionalContext (no safe outlet
mid-run; pinned), owns a run-scoped abort that follows the outer signal in
and fires on settlement (in-flight sub-dispatch aborted, queued abandoned,
queue drained before returning), and converts a failed run into
CodeRunFailedError → a structured isError carrying kind + captured logs.
tool/code-dispatch joins SessionEventMap by declaration merging (log-only;
deriveMessages ignores it).
The composed surface: the tools config forwards through agent-core and
both app packages; examples/code-agent + demo:code run the worker runtime
under mode code (keyless boot smoke + a with-key e2e proving the collapsed
[run_code] header, the dispatch events, and the file the program wrote);
two new snapshot scenarios (code-mode-turn, both-mode-turn) record the SDK
section, collapsed header, dispatch events, and result card — each its own
header-pinning class (the harness gains per-scenario config overlays and
per-class pins). Catalogs, graphs, cookbook, hooks-bridge notes, and the
RFC (moved to implemented/, restructured to decision-era headings) updated
in the same change.
Model-facing tool-call budgets were tangled into each capability's schema
(bash timeoutMs, web_fetch timeout_ms) with no shared home. Add a
tools/execute around-dispatch waterfall to dsh-tools whose base next() is
the dispatch-with-normalization thunk, and a new @deepseek-ai/dsh-timeout-policy
plugin (packages/timeout/) that arms a per-tool deadline on exec.signal and
returns a structured TOOL_TIMEOUT when it wins. Migrate web_fetch (drop the
model-facing timeout_ms) and web_search onto it; the fetch provider keeps its
timeout only as a resource backstop for direct callers. bash and hook command
execution keep BASH_TIMEOUT unchanged.
Named the plugin timeout-policy (not the RFC's tool-timeout) so it does not
trip the gen-tool-catalog packages/*/tool-* completeness guard, and replace
exec.signal by in-place mutation before next() since cordis waterfall next()
ignores passed arguments. RFC moved to implemented/ recording both deviations.
The package, coverage, and permission scripting all shipped on this
branch, so the RFC moves to implemented/ with the lifecycle rewrite:
Proposal becomes a present-tense Decision, Acceptance criteria and Risks
fold into Testing/Consequences with what actually pinned each one (the
zero-byte extraction parity, the 100% per-file coverage via the fake
bin, the vitest-in-src caveat, the per-suite pin cost).
The harness, normalizers, and suite/guard logic live inside
examples/acp-agent/tests, outside the coverage gate and copyable-only
for a second suite. Propose @deepseek-ai/dsh-acp-snapshot under
packages/support: parameterized runScenario, verbatim normalizers, a
defineAcpSnapshotSuite factory with per-suite header pinning, and
scripted permissionAnswers so an approval round-trip is expressible at
the snapshot tier — the sandbox composition is the immediate consumer.
Supersedes the add-on-plugin + node:vm-stub draft in place (still proposed/):
code mode becomes a first-class ToolRegistry presentation mode
('native' | 'code' | 'both'), execution goes behind a new ctx.codeRuntime
capability seam whose shipped backend is one fresh Node worker thread per
run (type-strip, empty env, resource limits, hard terminate), at
bash-equivalent trust with no unsafe-flag ceremony. Renames the file to
2026-06-15-code-mode.md and regenerates the RFC index.
Out-of-process delegation to external coding agents as two new subagent
seam backends, exposed as subagent_claude_code / subagent_codex tools.
Verified against @anthropic-ai/claude-agent-sdk 0.3.202 and codex CLI
0.142.5 via keyless spikes; includes the dsh-subagent-process extraction
plan, isolation/permission stances, and tiered test coverage.
The deliverable is plan mode — retitle and reorder the proposal opener so
the feature leads and the logged session-mode state is its implementation
property. Fix the Codex citation in the boolean-planMode alternative: Codex
has plan mode (/plan); its ACP mode list carries its approval presets — two
different surfaces. Durable vocabulary (mode/set, ctx.modes, dsh-mode) stays
string-shaped so a second mode never renames logged event types.
A session mode is a named, logged, per-agent policy state: mode/set as a
log-only SessionEventMap member (todo/write shape), a foldMode over the log,
soft enforcement at system-prompt/assemble (filtered schemas + mode section,
auto-logged as request/header-delta), hard enforcement at tools/pre-execute
(deny-by-default against the mode allowlist), and a thin ctx.modes service
with turn-boundary pending-intent flush for user flips. One new product
package dsh-mode (packages/mode/mode, the approval-group shape); plan is the
only shipped definition.
Lands as ONE feature — a plan mode without a model-driven, approvable exit is
not a smaller version of the feature. The roadmap's two stages are build-and-
review order for a single stacked landing: the mode core, then exit_plan_mode
(ask-gated through the approval seam; the plan text rides the tool args as
the reviewable log artifact), the stdio readline answerer, and the ACP
session-mode surface (session/set_mode, current_mode_update, available
modes). Hard prerequisite: the approval seam lands first; the stack bases on
feat/sandbox-support meanwhile.
Every session.jsonl fixture embedded the full composed system prompt and
complete tool-schema list in its request/header event (~8 KB on one line,
identical across the suite), so any prompt or tool-schema edit forced a
re-record or hand-edit of every fixture — see the dynamic-workflows PR for
the churn pattern this removes.
Now exactly one scenario (text-turn, flagged pinsHeader) commits and
compares that content verbatim; every other fixture stores and compares it
as {{system}}/{{tools}} tokens via the new pure scrubRequestHeaders
normalizer (applied to both compare sides and to record-mode writes, so a
re-record cannot reintroduce the content). request/header-delta payloads
are scrubbed the same way; config/reason stay verbatim — a model swap
SHOULD churn every fixture, a prompt edit should not. Replay is unaffected:
script derivation reads only assistant/chunk events.
Fixture meta-guards enforce the split: non-pinning fixtures must be fixed
points of the scrub, the pinning fixture must not be, and exactly one
scenario pins. Committed fixtures migrated through the same function.
Docs: pinned-header RFC (implemented/testing), base snapshot RFC + testing
policy + llm-replay module doc/README updated.