System Prompt Assembly
The system-prompt package owns the data exchanged between prompt contributors and one assembly call. The package README documents registration, ordering, scoping, and rendering behavior; this page records the exact cross-package types that plugins implement or pass.
Source: packages/core/system-prompt/src/index.ts.
Assembly context
AssembleContext identifies the scope layer one assembly resolves and may carry the explicit control signal for that request. It is merge-extensible: dsh-agent adds the optional live agent field, and assembleContextFor(agent, signal) sets the explicit fields together. A bare assembly has neither scope nor signal.
/** Merge-extensible context for one prompt assembly. */
interface AssembleContext {
/**
* Scope whose providers and waterfall listeners participate. When absent,
* only global providers and subject-less listeners participate.
*/
scope?: ScopeKey
/** Explicit control signal for the turn that requested this assembly, when any. */
signal?: AbortSignal
}Tool-provider result
ToolProviderResult.schemas is the model-visible set for the current assembly. knownNames is the provider's pre-restriction name universe used to distinguish a configured-name typo from a known tool that is deliberately hidden in this scope.
/** Tool schemas visible in one assembly and their pre-restriction name set. */
interface ToolProviderResult {
/** The schemas this provider contributes to THIS assembly. */
readonly schemas: readonly ToolSchema[]
/** The pre-restriction name universe for config validation (defaults to `schemas`' names). */
readonly knownNames?: readonly string[]
}Prompt sections
PromptSection is a readonly same-process registration contract. Its text may be static or resolved from the current assembly context. One effective complete section becomes the sole prompt section after cooperative assembly.
/** One contributed section of the system prompt (registry input). */
interface PromptSection {
/** Unique name — a duplicate registration throws (see {@link SystemPrompt.section}). */
readonly name: string
/**
* Sections are concatenated in ascending order. Convention: `-100` is the
* harness identity, `0` the deployment persona, tool guidance uses 100–199;
* other negative orders also render before the persona.
*/
readonly order: number
/**
* Static text or a provider evaluated at each assembly with that assembly's
* {@link AssembleContext}. The text may reference `{{variable}}`s — they are
* interpolated later, by {@link renderPrompt}.
*/
readonly text: string | ((context: AssembleContext) => string)
/**
* Treat this contribution as the complete system prompt. Assembly still
* runs the cooperative waterfall so tools, contexts, and variables can be
* resolved, then restores this exact section as the sole prompt section.
* More than one effective complete section makes assembly fail.
*/
readonly complete?: boolean
}Dynamic prompt context
PromptContext is the cache-safe counterpart to PromptSection. The assembly resolves and orders these contributions, while agent-loop logs their complete current snapshot after retained model history only when it changed or compaction removed it.
/** Dynamic model context materialized as a durable user-role snapshot. */
interface PromptContext {
/** Unique name — a duplicate registration throws (see {@link SystemPrompt.context}). */
readonly name: string
/** Contexts are joined in ascending order. */
readonly order: number
/** Static text or a provider evaluated for each assembly. Empty text contributes nothing. */
readonly text: string | ((context: AssembleContext) => string)
}Cordis API
Generated from source by scripts/gen-cordis-catalog.ts (verified fresh by pnpm run verify-cordis-catalog in doc-sync; regenerate with pnpm run gen-cordis-catalog) — this section is byte-identical in both language sides of the page. Signature blocks use a ts cordis-catalog fence and keep the original source JSDoc; dispatch modes are defined in the primer, and the framework-inherited ctx API lives in cordis-api/inherited.md.
ctx.systemPrompt — SystemPrompt
Registry service for the prompt inputs assembled before each model step.
/**
* Register an ordered prompt section in the calling context's scope. A scoped
* section shadows a global section with the same name; duplicates within one
* layer and non-finite orders throw. Registration and disposal emit
* `system-prompt/change`.
* @param section - the section to register.
* @returns the exact Cordis effect disposer.
*/
section(section: PromptSection): () => void
/**
* Register ordered dynamic context in the calling context's scope. Scoped
* entries shadow global entries with the same name.
* @param context - the context contribution to register.
* @returns the exact Cordis effect disposer.
*/
context(context: PromptContext): () => void
/**
* Suppress every dynamic runtime-context contribution in the calling
* context's scope without changing the services that own or enforce those
* facts. Multiple suppressors remain independently disposable.
* @returns the exact Cordis effect disposer.
*/
suppressRuntimeContext(): () => void
/**
* Register a tool-schema provider in the calling context's scope. Global and
* matching scoped providers both contribute; returning the reserved
* {@link TOOL_ORDER_REST} name makes assembly fail.
* @param provider - evaluated for each assembly with its context.
* @returns the exact Cordis effect disposer.
*/
tools(provider: (context: AssembleContext) => ToolProviderResult): () => void
/**
* Register a prompt variable in the calling context's scope. Scoped values
* shadow globals; invalid or duplicate names throw. A provider may return
* `undefined`, but rendering a section that references that value then fails.
* @param name - the `[a-z][a-z0-9_]*` reference name.
* @param provider - evaluated for each assembly.
* @returns the exact Cordis effect disposer.
*/
variable(name: string, provider: (context: AssembleContext) => string | undefined): () => void
/**
* Assemble global and scoped providers, detach tool parameters, apply
* canonical ordering, then run the assembly waterfall. Scoped sections and
* variables shadow globals. The returned waterfall value is authoritative
* except that an effective complete section is restored afterwards as the
* sole prompt section.
* @param context - the optional scope and plugin-defined assembly fields.
* @returns the post-waterfall assembly with any complete prompt enforced.
*/
async assemble(context: AssembleContext = {}): Promise<PromptAssembly>Source: packages/core/system-prompt/src/index.ts:338
system-prompt/* events
system-prompt/assemble — waterfall
Expert waterfall over the assembled sections, contexts, tools, and variables. Scope-filtered dispatch (@deepseek-ai/dsh-scope): scoped listeners receive only that scope's assemblies. The returned value is authoritative. A supplied signal controls only this explicit assembly request and must not be retained to control later turns. A registered complete section is restored after this waterfall, so listeners cannot add to or replace that scope's system prompt.
/**
* Expert waterfall over the assembled sections, contexts, tools, and variables.
* Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): scoped listeners
* receive only that scope's assemblies. The returned value is authoritative.
* A supplied signal controls only this explicit assembly request and must not
* be retained to control later turns. A registered complete section is
* restored after this waterfall, so listeners cannot add to or replace
* that scope's system prompt.
* @param assembly - the mutable assembly built from registered providers.
* @param context - the caller's per-assembly context.
* @mode waterfall
*/
'system-prompt/assemble'(this: Scoped<SystemPrompt>, assembly: PromptAssembly, context: AssembleContext, next: () => Promise<PromptAssembly>): Promise<PromptAssembly>Types: Scoped
Source: packages/core/system-prompt/src/index.ts:31
system-prompt/change — emit
Emitted when any prompt provider changes. This registry notification is unfiltered because a global change affects every scope.
/**
* Emitted when any prompt provider changes. This registry notification is
* unfiltered because a global change affects every scope.
* @mode emit
*/
'system-prompt/change'(): void