[leehack]

Summary

• Correct the LlamaBackend.withTextHistory and LlamaEngineCapabilities.supportsToolCalling Dartdoc and example/README.md: automatic tool loops run on LiteRT-LM Web withTextHistory when the load-time token-count probes pass; default constructors still refuse them.
• coverageErrors now reports Duplicate exemption id; new test fails first on a duplicated id (e.g. renaming litert-web-tool-calling-profile to litert-web-text-history-profile).
• Reword the Unreleased LiteRT-LM Web manual tool calling on @litert-lm/core 0.19.0 #1790 changelog bullet (both changelogs) so it no longer says automatic loops throw; broaden the withTextHistory Dartdoc first line and tighten the example README wording.
• Other docs and both skills/ files already state the current behavior; MIGRATION.md 0.10 to 0.11 wording is historical and left as is.

Refs #1861, plan #1874.

Production-readiness scope

• User-facing scope: Accurate Dartdoc and example guidance; no behavior change.
• Supported platforms/paths: Docs/Dartdoc and a tooling test only.
• Unsupported or intentionally unavailable paths: Unchanged.
• Out of scope / follow-ups: None.

Completeness checklist

• Declared scope is fully implemented, or explicitly reduced above.
• Unsupported platform/option combinations fail loudly with actionable diagnostics or are clearly documented as unavailable.
• Public API docs, README/website docs, examples, support matrices, and changelog entries are updated where relevant. (No changelog: Dartdoc correction.)
• Regression coverage covers the original issue plus key negative/version-skew paths where relevant.
• Public capability changes update the validation coverage registry: N/A, no capability change.
• Security/privacy review completed: nothing sensitive touched.
• Follow-up work tracked: None.

PR type guidance

• Docs-only PR: No runtime behavior change (Dartdoc comments only in lib/). Docs site not changed.

Test Plan

• dart run tool/prepare_workspace.dart
• dart format --output=none --set-exit-if-changed .
• dart analyze
• dart test -p vm -j 1 --exclude-tags local-only N/A: ran test/unit/tooling/ (CI runs the rest)
• dart test -p chrome --exclude-tags local-only N/A: no Web behavior change
• coverage-lib N/A: no lib/ behavior change
• test/unit/tooling/: all pass except 6 windows_registry_qualification_test.dart cases needing pwsh, absent locally. validation_coverage_test.dart passes; the new test fails without the check.

Matrix Evidence

Matrix row	Scope covered	Platform / model / backend	Result	Evidence / notes
all	Docs/Dartdoc and tooling test	N/A	N/A	No runtime change; classified high-risk only because backend.dart is a backend-runtime path

Review Notes

• Independent review status: N/A, comment-only change to production files.
• CI status / head SHA: pending / e5f958a

High-risk regression review

• Classification: high-risk (surface backendRuntime, comment-only edits in lib/src/backends/backend.dart and lib/src/core/engine/engine_capabilities.dart)
• Implementation task: this PR
• Independent blocking QA task: fresh auditor sessions, content PASS at db9cf4b6 and delta PASS at e5f958a8 (fresh-agent-auditor-1896b), 0 PR-caused P1
• Maintainer waiver (one-time): the readiness evaluator rejects (missingTestPath) only because the edited supportsToolCalling Dartdoc block in engine_capabilities.dart already contains @litert-lm/[email protected], which _activeComment treats as a directive, so the file can't take the comment-only route and no test can cover a Dartdoc sentence. The auditor proved the edit comment-only (266/266 code tokens identical); a control without that hunk exits 2. Maintainer approved a one-time waiver for this file on 2026-11-10 ("One-time waiver (Recommended)"), as with Let export-only public entrypoint diffs skip structured-output minima #1806. Evidence: llamadart-evidence/pr-1896/ (real head exit 1, control exit 2).
• Exact head / current base: e5f958a8 / main ba4e0e1b
• Production-branch deletion, bypass, or miswire proof: N/A, Dartdoc only
• Affected-family real-model/artifact evidence: N/A, no behavior change
• Explicit unavailable-family or other N/A evidence: N/A
• Known PR-caused P1 regressions: 0
• Unresolved review threads: 0

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