[leehack]

Summary

• Seed-OSS wording: the guide and seed_oss_parallel_upstream.md now say Seed-OSS requests refuse ToolDefinition.fromJsonSchema tools at render, so apps validate tool name and arguments before running a call (as the 0.19.4 changelog does).
• Test pins for #1861 open items: runtime ToolCall.id passthrough and withheld content kept in the merged Web parse result (Add LiteRT-LM Web manual tool calling on @litert-lm/core 0.19.0 #1880 audit); addTearDown and an accurate name for the C API 1.0 send-failure stack test (Pin LiteRT-LM C API 1.0 send-failure text and stack (#1861 sweep 2) #1888); companion pub example selection (Test companion pub content-size check in the release verifier (#1861 sweep 2) #1889); deterministic regression test for #1892 (Fix Chrome supervisor post-done window starting before reporter_done #1893); LiteRT-LM Web limit-probe regex anchors (Report LiteRT-LM Web token-limit truncation and run automatic tool loops there #1891); MiniMax M3 exact-stream-flag guard and empty-leading-thought plus unfinished second <mm:think> and call (Take a MiniMax M3 thought only where it starts the reply, as llama.cpp does (#1887) #1894).
• Chat app truncation notice also names a full context; runtime-ownership doc cost figure now "about 20-125 ms at 65536 on Qwen3 0.6B CPU".

Refs #1861 (tracker not ticked).

Production-readiness scope

• User-facing scope: docs wording, tests, one example-app message. No lib/ change.
• Supported platforms/paths: all; the supervisor test is Linux-only.
• Unsupported or intentionally unavailable paths: N/A
• Out of scope / follow-ups: the remaining open 0.19.x audit follow-ups (index) #1861 items are listed on the tracker (chunking-dependent MiniMax M3 forced-open stream cases found while pinning E4 go to a separate issue).

Completeness checklist

• Declared scope is fully implemented.
• Unsupported platform/option combinations: N/A (no behaviour change).
• Docs updated; no changelog (no user-visible library change).
• Regression coverage: see mutation table.
• Validation coverage registry: N/A (no capability change).
• Security/privacy review: no secrets or paths touched.
• Follow-ups tracked on 0.19.x audit follow-ups (index) #1861.

PR type guidance

• Docs-only PR: N/A (tests and docs).

Test Plan

• dart format --output=none --set-exit-if-changed .
• Touched VM suites and test/unit/tooling (see CI)
• dart test -p chrome test/unit/backends/litert_lm/litert_lm_backend_web_test.dart
• docker run python:3.12 python -m unittest test.ci.test_supervise_chrome_test (Linux)
• (cd example/chat_app && flutter test test/unit_test.dart)
• coverage-lib: N/A, no lib/ change

Matrix Evidence

Matrix row	Scope covered	Platform / model / backend	Result	Evidence / notes
static-format-analyze	format	macOS	PASS
root-vm	touched suites	macOS VM	PASS
root-chrome	LiteRT-LM Web backend suite	Chrome	PASS
examples-tests	chat app unit test	macOS	PASS
docs-site	guide/maintainer wording	N/A	N/A	wording only; CI docs lane

Mutation checks (each test fails with the mutant, passes without):

Mutant	Result
supervisor done_at = now (pre-#1893)	new test_post_done_window_starts_after_a_slow_reporter_poll fails 3/3 on Linux
limit regex without ^ / without $	both new "text before/after" rows fail
merged Web parse id: null	new id test fails
merged Web parse content: ''	new withheld-content test fails
exactReplyStart without leadingThoughtOnly guard (E4)	new chunking test fails
takesThoughtOnlyAtReplyStart: false for minimaxM3	new empty-leading-thought test fails
endsAtFirstEndTag = verbatimThought	survives (not pinned; equivalent for the covered shapes)

Review Notes

• Independent review status: N/A, test and docs only
• CI status / head SHA: see checks

High-risk regression review

• Classification: standard
• Implementation task: N/A
• Independent blocking QA task: N/A
• Exact head / current base: N/A
• Production-branch deletion, bypass, or miswire proof: N/A
• Affected-family real-model/artifact evidence: N/A
• Explicit unavailable-family or other N/A evidence: N/A
• Known PR-caused P1 regressions: 0
• Unresolved review threads: 0

[github-actions]

Chat app preview removed for leehack/llamadart-chat-pr-1900.