Yichen Jiang
9d0c97b9d2
ctx.tools.register(definition, { when }) adds a synchronous or asynchronous
condition. AgentLoop resolves conditions once per proposed step with the
agent, the model selection that step preparation captured, and the turn
signal, before prompt assembly and agent/pre-step. The resulting
ResolvedToolSet governs tool declarations, Native dispatch, PTC bindings,
and nested calls for that step and its retries, and the turn disposes it
when the proposal is rejected or fails, when no step opens, and after the
step. A false condition removes the tool everywhere; a thrown condition
ends the turn with TOOL_ACTIVATION_FAILED. Calls whose registration was
replaced or removed during the step return UNKNOWN_TOOL.
system-prompt/assemble now transforms PromptPresentation without a tool
array, so tool declarations stay provider-owned. exit_plan_mode is declared
only for steps whose selected plan state is active, the same state that
renders plan guidance; it still rejects a call before the selection is
logged.
Model selection stays as master defines it; this change adds no model
selection event or Agent field.
description, kind
| description | kind |
|---|---|
| The core group map: the session log, system-prompt assembly, tool registry, agent vocabulary, and default loop that form the product API spine. | package-group |
packages/core
English | 中文
Summary
Use the core packages to build or extend an agent that records durable session history, assembles system prompts, exposes tools, selects a default model, and runs model turns. These packages define the shared APIs used by every composition, while executable product assemblies live under packages/bundle. Choose this group when developing agent behavior or replacing one of those capabilities; start with dsh-base when you need the default runnable composition.
Table of Contents
Packages
| Package | Role | ctx key |
|---|---|---|
scope/ |
Scoped registration and event routing that isolate one agent's contributions | library — no ctx key |
session/ |
The append-only session event log every agent's history derives from | ctx.sessions |
system-prompt/ |
System-prompt assembly from ordered sections, tool schemas, and variables | ctx.systemPrompt |
tools/ |
The tool registry and guarded execution pipeline the loop dispatches through | ctx.tools |
agent-tool-presentation/ |
Per-agent tool-presentation selector for presets | no ctx key |
agent/ |
The Agent handle plugins program against, plus its live registry and events |
ctx.agents |
agent-default-model/ |
The deployment default model selection entry points apply to fresh agents | ctx.agentDefaultModel |
agent-loop/ |
The default agent driver: creates agents and runs the turn and step lifecycle | ctx.agentLoop |
scope supplies the shared scoping primitive; agent owns the public Agent contract, while agent-loop is its default implementation, so extension plugins depend on agent and the driver stays swappable. agent-default-model owns the deployment selection an entry point applies when a session has none of its own. Runnable compositions live under packages/bundle; this group owns only the swappable spine pieces.
Related documentation
- Core subsystem — the package-by-package loop map and the
Agenthandle contracts. - Session subsystem — the session event vocabulary and derived history.
- System-prompt subsystem — prompt section, dynamic context, and tool-schema types.
- Tools subsystem — the tool execution pipeline and presentation vocabulary.
- Scoped registration subsystem — the scoped-layer primitive these registries build on.
- Architecture — the turn flow and where new behavior goes.
- Base bundle — the default product composition.
- SDK minimal bundle — a complete standalone composition with a deliberately smaller feature set.
Dev Note
Working context for maintainers — click to expand
None.