ea4c10d753
Review discussion converged on the industry shape (Claude Code caches user context per conversation; Codex separates initial context from diffs; Kimi appends at continuation boundaries to protect prompt caching): stable openers belong in a compose-once prefix, mid-session changes belong in append-only history — not in a per-request slot. agent/session-prefix fires ONCE per loop instance, lazily on its first request-building step: the composed Message[] is deep-frozen, cached on the transmission bookkeeping, recorded as EpochHeader.messagePrefix on the anchoring 'initial'/'resume' snapshot, and reused verbatim for every request the instance sends — prefix stability is structural, not a producer discipline, and a resume recomposes with attributable drift. The request is messagePrefix + boundary snapshot. The per-step RequestAdvice/RequestAdviceContext surface and the messageSuffix header field are dropped: the tail slot had no consumer, and every current update pattern (new AGENTS.md discovered, memory update, skills change) routes through the existing append-only history channels — inject(), tools/post-execute additionalContext, prompt-submit additionalContext — each paid once and prefix-cached thereafter. The messagePrefix delta arm stays for codec totality; the loop never produces one in practice.
Packages
Harness packages, all under the @deepseek-ai/dsh-* scope. Each package is a Cordis plugin (microkernel-style): it exports either a default Service subclass or a functional plugin, declares its ctx key/events through declaration merging, and exposes extension points through ctx.effect(), ctx.on(), and ctx.waterfall(). Authoring conventions: AGENTS.md (subtree) and the root AGENTS.md § Conventions.
Hierarchy
Packages are grouped by modular role at packages/<group>/<pkg>/. The group directory is a pure container (no package.json of its own); the package name stays @deepseek-ai/dsh-<pkg> regardless of group. Each group README is the canonical per-package map — package roles, ctx keys, and the product-vs-support split live there, next to the code.
| Group | Role | Release expectation |
|---|---|---|
core/ |
Product API spine: session, system-prompt, tools, agent, and the concrete loop | Product — stable surface |
llm/ |
LLM capability family: the abstract service + provider adapters | Product — stable surface |
bash/ |
Bash capability family: the executor seam, a local impl, and the model-facing tool | Product — stable surface |
fs/ |
Filesystem capability family: the abstract seam, a local impl, and the model-facing file tools | Product — stable surface |
compact/ |
Compaction capability family: the abstract seam + a basic backend (tool deferred) | Product — stable surface |
subagent/ |
Subagent capability family: the provider-registry seam and the model-facing delegation tool | Product — stable surface |
web/ |
Web capability family: the abstract seam, search/fetch provider impls, and the model-facing web tools | Product — stable surface |
todo/ |
Todo/planning family: the model-facing todo_write tool (whole-list task tracking on the session log) |
Product — stable surface |
hooks/ |
Hook bridges + the shared Claude Code / Codex wire-protocol library | Product — stable surface |
session-persistence/ |
Persistence capability family: the seam + JSONL/SQLite backends | Product — stable surface |
ui/ |
Editor/client integration surfaces (the ACP bridge) + the app packages | Product — stable surface |
support/ |
Dev/test/example infrastructure (invariants, replay adapter, subagent mock) | Support — lower compatibility expectations |
util/ |
Low-level zero-dependency utilities shared across groups (the Branded<B> primitive) |
Support — small, stable, harness-dep-free |
The split is the point: a package's group says whether it is part of the product API or support/test/example infrastructure, so release and removal decisions do not treat every package as an equal public contract. New packages join an existing group; adding a new top-level group is a deliberate act (extend the group READMEs and this table).
Dependencies
The inter-package dependency graph is generated: docs/module-graph.md (pnpm run gen-module-graph, freshness-gated in CI).
The rule it must obey: extension plugins depend on interfaces, never on the concrete loop. dsh-agent-loop is swappable — UI/hook/tool plugins keep working against the dsh-agent vocabulary if the loop is replaced. The sanctioned exception is a composition/bundle package like dsh-agent-core, whose whole job is to assemble the concrete spine: it depends on dsh-agent-loop (and the other concrete spine plugins) on purpose. The rule constrains plugins that EXTEND the system, not the bundle that COMPOSES it — swapping the loop means shipping a different bundle, not rewiring every extension. A swappable capability splits into interface / implementation / consumer packages (the bash trio is the template — see capability seams).
Each package has its own README.md with purpose, service API, events, extension points, and deliberate non-goals (TODOs).