Flat config with two layers. Correctness (type-checked): the headline rules for this codebase are no-floating-promises / no-misused-promises (a lost promise in the agent loop is our primary bug class), switch-exhaustiveness-check (we switch over merge-extensible unions everywhere), no-unnecessary-condition, require-await, and no-explicit-any. Style (@stylistic): 2-space, no semicolons, single quotes, trailing commas, max-len 140 — the existing house style, now enforced instead of drifting between agents. vendor/ is excluded (vendored source keeps upstream style); tests relax the rules that fight test ergonomics (non-null assertions after expects, async mock signatures, non-Error throws). Code adjusted to pass: registry disposers wrap ctx.effect's promise-returning disposer behind a sync () => void (our public API), BlockAssembler gains an invariant-checking mustGet instead of non-null assertions, lastTurnNumber uses findLast, waterfall tails return Promise.resolve instead of async-without-await arrows, and the two deliberate suppressions (non-exhaustive derivation switch, unbound execute pass-through) carry justification comments. yarn lint / yarn lint:fix added.
dsh-system-prompt
System prompt assembly registry. Plugins contribute ordered text sections and
tool-schema providers; the agent loop calls assemble() once per step.
Service: SystemPrompt (ctx key: systemPrompt)
Public API
ctx.systemPrompt.section(section: PromptSection): () => voidContribute a section. Disposed with the calling fiber.ctx.systemPrompt.tools(provider: () => ToolSchema[]): () => voidContribute tool schemas (evaluated at each assembly). Disposed with the calling fiber.ctx.systemPrompt.assemble(): Promise<PromptAssembly>Assemble the current prompt. Runs through thesystem-prompt/assemblewaterfall.
Events
| Event | Mode | Purpose |
|---|---|---|
system-prompt/assemble |
waterfall | Mutate/extend the assembly before it reaches the model |
system-prompt/change |
emit | A section or tool provider was registered or unregistered |
Key types
PromptSection—{ name, order, text: string | (() => string) }. Sections are concatenated in ascendingorder.PromptAssembly—{ sections: PromptSection[], tools: ToolSchema[] }. Tool schemas are part of the assembly by design: "what the model is told it can do" is one coherent thing, even though adapters transmit schemas as a separate wire field.renderPrompt(assembly)— joins section texts with blank lines.
Merge-extensible: plugins can declare extra fields on PromptAssembly via
declaration merging.
Extension points
- Section providers: AGENTS.md reader, cwd notifier, persona config, etc.
- Tool schema providers:
ToolRegistryregisters itself as a tool provider automatically. - The
system-prompt/assemblewaterfall: mutate or replace the assembly (system-prompt configurability, dynamic tool filtering).
What is NOT here
- Any hardcoded prompt text — every section comes from plugins.
- Prompt compaction (belongs on the
agent/requestseam indsh-agent).