deepseek-harness/packages/README.md

Packages

Harness packages, all under the @deepseek-ai/dsh-* scope. Each package is a Cordis service (microkernel plugin-style): it exports a default Service class that gets registered via ctx.plugin(), declares its ctx key and events through declaration merging, and exposes extension points through ctx.effect(), ctx.on(), and ctx.waterfall().

Dependency graph

dsh-llm          (no harness deps — pure vocabulary)
dsh-bash          (no harness deps — abstract executor seam)
dsh-session       ← dsh-llm
dsh-system-prompt ← dsh-llm
dsh-agent         ← dsh-llm, dsh-session
dsh-tools         ← dsh-llm, dsh-system-prompt, dsh-agent
dsh-bash-local    ← dsh-bash                       (BashExecutor impl)
dsh-tool-bash     ← dsh-bash, dsh-tools            (bash tool schemas)
dsh-llm-deepseek  ← dsh-llm                        (DeepSeek adapter)
dsh-llm-pi-ai     ← dsh-llm                        (pi-ai-backed adapter)
dsh-agent-loop    ← dsh-llm, dsh-session, dsh-system-prompt, dsh-tools, dsh-agent

The rule: 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. A swappable capability splits into interface / implementation / consumer packages (the bash trio is the template — see ADR 0009).

What goes where

Package	Role	ctx key
llm/	Abstract LLM service + content-block vocabulary + chunk assembler	ctx.llm
session/	Event-sourced session log + in-memory store	ctx.sessions
system-prompt/	Prompt-section + tool-schema assembly registry	ctx.systemPrompt
tools/	Tool registry + tools/execute waterfall	ctx.tools
agent/	Agent interface, registry, agent/* event vocabulary	ctx.agents
agent-loop/	THE concrete plugin: LoopAgent + the loop driver	ctx.agentLoop
bash/	Abstract bash executor seam (interface + vocabulary)	ctx.bash
bash-local/	Local-subprocess BashExecutor implementation	(registers ctx.bash)
tool-bash/	Model-facing bash/bash_output/bash_kill tool schemas	(registers on ctx.tools)
llm-deepseek/	DeepSeek API adapter (hand-rolled fetch/SSE)	(registers on ctx.llm)
llm-pi-ai/	DeepSeek adapter via @earendil-works/pi-ai (design twin)	(registers on ctx.llm)

Each package has its own README.md with purpose, service API, events, extension points, and deliberate non-goals (TODOs).

Conventions (applied across all harness packages)

• Registrations are effects: every contribution (adapter, tool, section, agent, event listener) goes through ctx.effect() / ctx.on(), so disposal and HMR clean up automatically. Every register() returns the disposer.
• Declaration merging for events and ctx: services declare their events in declare module 'cordis' { interface Events { ... } } and their ctx key in interface Context.
• Waterfall semantics: ctx.waterfall listeners receive (...args, next) and MUST call next() to delegate; returning without it short-circuits (the veto mechanism).
• Extensible unions: ContentBlockMap, MessageSourceMap, FinishReasonMap, TurnTriggerMap, TurnEndReasonMap, and SessionEventMap use the merge-extensible-map pattern so plugins can add variants via declaration merging.
• ESM everywhere; imports use package names across package boundaries, .ts extensions within a package.
• Tests: vitest, colocated under packages/<name>/tests/*.spec.ts. Every registry needs an HMR-safety test. Err on the side of more tests.