a5aa1185b1
Long research turns failed mid-task with "Lost connection to the AI provider".
Node's global fetch (undici) defaults BOTH headersTimeout and bodyTimeout to
300_000ms, and the chat provider + the external-MCP dispatcher both ran on it
with no override, so:
- the z.ai chat stream dropped when a late step's huge accumulated context
pushed the model's time-to-first-token past 5 min (reproduced: even a trivial
glm-5.2 query has a ~4-8s first-chunk latency; the live telemetry shows it
scaling with context — and a long run reaches 400k+-token steps), or a
reasoning model paused >5 min between chunks (bodyTimeout);
- the crawl4ai SSE transport, held open across the whole turn, dropped when it
idled >5 min between tool calls — a tool failure that aborts the turn and
surfaces the same banner.
Fix: a dedicated undici dispatcher with both stream timeouts DISABLED (0) on each
path. Cancellation is unchanged — the turn is bound to the request abortSignal
(client disconnect) and capped by MAX_AGENT_STEPS, so it still terminates; it
just no longer dies at an arbitrary 5-minute wall-clock.
- ai-streaming-fetch.ts: createStreamingFetch() (+ exported option contract).
- ai.service: the chat provider's fetch is now createStreamingFetch(), wrapped
by the existing passive ECONNRESET telemetry (createDiagnosticFetch gained an
optional baseFetch) so the telemetry observes the SAME transport the turn
uses.
- mcp-clients: headersTimeout/bodyTimeout: 0 on the SSRF-pinned Agent.
Investigation: reproduced the transport mechanism against the real z.ai endpoint
(a 1ms headersTimeout throws UND_ERR_HEADERS_TIMEOUT — the exact drop) and ran
the actual research agent to a ~428k-token context. Verified the fixed path
streams cleanly live (glm-5.2 turns finish; telemetry confirms the streaming
fetch is in use).
Tests: ai-streaming-fetch.spec (option contract + streams a delayed response);
ai-http-diagnostics + ai/mcp specs green. server tsc clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
A progressive Node.js framework for building efficient and scalable server-side applications.
Description
Nest framework TypeScript starter repository.
Installation
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$ npm run migration:revert
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$ npm run migration:revert
# Shows the list of executed and pending migrations
$ npm run migration:show
## Test
```bash
# unit tests
$ npm run test
# e2e tests
$ npm run test:e2e
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$ npm run test:cov
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