Files
commitea/packages/core/src/agent/agent-loop.ts
Croissant Le Doux dbcdcda5e7 feat: stream Reginald's replies token-by-token
The 26b is slow (~30s/call); the chat now shows the answer forming instead of
freezing until it's done. The final prose streams over SSE; tool-calling turns
stay structured (no partial tokens), so streaming kicks in for the narration.

core (@commitea/core):
- chat-client.complete gains an optional onToken — when set, it requests
  stream:true and parses the OpenAI SSE stream, emitting content deltas and
  assembling streamed tool-call argument fragments into the final result.
- GiteaHttpResponse exposes the optional `body` stream (real fetch has it; stubs
  don't). agent-loop threads onToken to each completion.

app:
- model:chat forwards each delta to the renderer (event.sender.send); preload
  exposes model.onToken(cb) → unsubscribe. useChat accumulates the live stream
  into a growing bubble (with a cursor), replaced by the authoritative final
  content when the turn resolves. Unconfigured → scripted reply, unchanged.

Verified: 118 core tests green (2 streaming: SSE content deltas + tool-call
fragment assembly), desktop typecheck clean, 14 fixture e2e green. Live: a real
turn against gemma-4-26b assembles the correct answer via the streaming path
(live-reginald green) — the reply now renders token-by-token.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-09 00:22:12 -04:00

72 lines
2.7 KiB
TypeScript

/**
* The agent turn loop. Given a model `complete` fn, the conversation, the tool
* declarations, and an `execute` that actually runs a tool, it drives the
* call→tool→result→call cycle until the model answers in prose (or a step
* budget is hit). Pure orchestration with injected I/O — the model and the tool
* executor are both stubbable, so the loop is fully unit-testable offline.
*/
import type { ChatMessage, CompletionResult, ToolDecl } from './chat-client.js'
/** A tool the loop ran, with the raw args and its stringified result — for the UI's activity trail. */
export interface AgentStep {
tool: string
arguments: string
result: string
}
export type ToolExecutor = (name: string, args: unknown) => Promise<unknown>
export interface AgentTurn {
content: string
steps: AgentStep[]
/** The full conversation including this turn's assistant/tool messages. */
messages: ChatMessage[]
}
const DEFAULT_MAX_STEPS = 4
function stringify(result: unknown): string {
return typeof result === 'string' ? result : JSON.stringify(result)
}
export async function runAgentTurn(opts: {
complete: (messages: ChatMessage[], tools?: ToolDecl[], onToken?: (delta: string) => void) => Promise<CompletionResult>
messages: ChatMessage[]
tools: ToolDecl[]
execute: ToolExecutor
maxSteps?: number
/** Streams content deltas as the model produces prose (final-answer streaming). */
onToken?: (delta: string) => void
}): Promise<AgentTurn> {
const maxSteps = opts.maxSteps ?? DEFAULT_MAX_STEPS
const convo: ChatMessage[] = [...opts.messages]
const steps: AgentStep[] = []
for (let step = 0; step < maxSteps; step++) {
const { content, toolCalls } = await opts.complete(convo, opts.tools, opts.onToken)
if (toolCalls.length === 0) {
convo.push({ role: 'assistant', content })
return { content, steps, messages: convo }
}
convo.push({ role: 'assistant', content, toolCalls })
for (const tc of toolCalls) {
let result: unknown
try {
const args = tc.arguments ? JSON.parse(tc.arguments) : {}
result = await opts.execute(tc.name, args)
} catch (e) {
result = { error: e instanceof Error ? e.message : String(e) }
}
const resultStr = stringify(result)
steps.push({ tool: tc.name, arguments: tc.arguments, result: resultStr })
convo.push({ role: 'tool', toolCallId: tc.id, name: tc.name, content: resultStr })
}
}
// Out of tool budget — force a final prose answer with tools withheld.
const final = await opts.complete(convo, [], opts.onToken)
convo.push({ role: 'assistant', content: final.content })
return { content: final.content, steps, messages: convo }
}