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Evidence record / pi-coding-agent

A dated record of one change, kept so the writing that cites it can be checked. Compiled from the sources listed below by the research run, not written for reading. The judgment lives in the issues that cite it, below.

2026-10-13-pi-coding-agent-custom-stream-functions-must-return-assistantmessageeventstream-from-1-1

Custom stream functions must return AssistantMessageEventStream from 1.1.0. Custom stream functions must return AssistantMessageEventStream; a handwritten generic EventStream subclass no longer type-checks in its place. The change also records response durationMs and optional tool-result durationMs. Deferred results fetched later remain untimed.

Channel: tagged-release. Half: both. Date: 2026-10-07.

Operator consequence: Use createAssistantMessageEventStream or the concrete AssistantMessageEventStream contract in custom adapters. Keep measured response/tool durations distinct from deferred work with no recorded duration.

Receipt

Finding metadata

Confidence
high

Run: 2026-10-13-profile-refresh-2026-09-21_2026-10-13-frontier-v0

Finding ID: 2026-10-13-pi-coding-agent-custom-stream-functions-must-return-assistantmessageeventstream-from-1-1

Profile citations

Source links

Primary links, including exact changelog lines when available.

  1. Pi Coding Agent
    commit2026-10-13-pi-coding-agent-custom-stream-functions-must-return-assistantmessageeventstream-from-1-1github.com/earendil-works/pi/commit/36a686ee8dd73afe8242011db387040890e24093tagged commit file2026-10-13-pi-coding-agent-custom-stream-functions-must-return-assistantmessageeventstream-from-1-1earendil-works/pi / packages/ai/CHANGELOG.md#L5-L12

Versioned source: run artifact