Evidence record / flue
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.
2026-08-10-flue-flue-v2-0-2-publishes-an-agent-behavior-reference-page-stating-the
Flue v2.0.2 publishes an Agent Behavior reference page stating the runtime's built-in limits as a versioned contract.
A new reference page collects the out-of-the-box runtime contract in one place: built-in tool parameters and truncation limits, environment defaults, message admission and turn-boundary joining, context composition and compaction, and the enforced limits. The live page states read truncates at 2000 lines or 50 KB (whichever hits first), bash tail-truncates at 2000 lines or 50 KB, grep caps at 100 matches and 500 characters per line, glob at 1000 paths, the compaction reserve is model-aware and capped at 20,000 tokens with 8,000 tokens kept verbatim by default, and delegation depth is capped at 4 (a deeper task chain fails).
Channel: tagged-release. Ancestry: The announcement of the page is a CHANGELOG entry inside stable tag v2.0.2 (gh api repos/withastro/flue/compare/v2.0.2...a171cc1bc8a552775a820ae3d343ccd09597cc8c -> status "identical"). The docs page itself is an unversioned marketing/docs surface with no tag or SHA behind it -- I fetched flueframework.com/docs/reference/agent-behavior/ directly and it resolves with the sections and numbers below, but that URL is a moving target and is cited as the docs surface only. The receipt for the change is the tagged changelog, not the page.
Operator consequence: Read it before you attribute an agent's failure to the model. Most of the "the agent didn't see the file" and "the agent lost the thread" reports in a harness like this are one of these numbers firing silently, and until now you had to read source to find them. Two are worth writing into your own runbook: the delegation depth cap of 4 is a hard failure, not a degradation, and the 8,000-token verbatim keep is what actually survives compaction. Standing on a docs page, not on code -- verify each number against your own runtime before you design around it.
Receipt
Finding metadata
Run: 2026-08-10-weekly-digest-2026-08-03_2026-08-10-frontier-v0
Finding ID: 2026-08-10-flue-flue-v2-0-2-publishes-an-agent-behavior-reference-page-stating-the
Source links
Primary links, including exact changelog lines when available.
Versioned source: run artifact