v0.2.1 — Tool execution fixes

Patch release for the AF-79 tool-execution defects in v0.2.0, published from verified commit 58774a67c3398f1e13c86fba6bb611cb40c1b10b.

Fixes

• Enforce max_concurrent_tools across overlapping batches on a shared engine, with FIFO admission and results kept in input order.
• Charge completed execution time before admitting queued calls against max_total_runtime_ms. Queued calls observe the current per-turn runtime and call-count budgets.
• Preserve occupied capacity through cancellation and turn changes; prevent stale queued calls from dispatching or old completions from charging a new turn.
• Match sidecar tool normalization: last definition wins, duplicate allowed names resolve once, and definitions follow sorted Unicode scalar name order. Empty or unresolved tool selections register no tools.
• Use exact Unicode tool identity for native handler and confirmation-policy lookup; a native call without a handler registered under its exact spelling fails rather than invoking a canonically equivalent tool's handler.
• Preserve declared webhook headers, including case-insensitive Content-Type, and supply the JSON default for non-GET requests only when that header is absent.

The runtime budget is cumulative admission control. Concurrent calls already admitted may exceed it, and an uncooperative host handler is not forcibly cancelled. Normalization order changes intentionally correct the previous Swift-only manifest-order behavior.

Verification

• Exact-commit main CI: successful. macOS and iOS each passed 196 package/model tests with one documented skip and zero failures. Simulation UI passed 4/4 on macOS and 5/5 on iOS. Applicable SDK builds, pinned-schema provenance, negative-drift checks, and CLI dry run passed.
• The macOS skip was the hosted on-device model availability test. The iOS skip was the optional sibling-schema lookup; the independent pinned-schema provenance check passed.
• Corrected-head local package tests passed 197/197, and focused policy/engine/identity checks passed 28/28, without skips. The reviewed head has the same tree as this release commit.
• Companion AgentFactory contract CI passed 11/11 without skips after documentation PR #18.

Public protocols, stream event shapes, supported schema versions, and platform floors are unchanged. Verification used injected handlers/transports and Simulation UI; it does not establish live-provider generation or physical-device offline acceptance. AF-84 remains deferred.

Runtime fix PR #5 · Full comparison from v0.2.0

Known Issues — Apple Foundation Models (2026-10-08)

Apple lists unexpected responses to prompts and instructions as Foundation Models known issue 152318091 in the macOS 26 release notes. Apple also documents runaway generation and context-window exhaustion, along with instruction-following limitations. These are upstream Foundation Models issues and limitations relevant when using SAR's Foundation Models adapter.

Testing with this adapter on macOS 26.6 has produced repeated or stale responses, incorrect use of conversation context or requested actions, and subsequent stalled or failed requests. The cause of this specific sequence remains under investigation. The macOS 26.6 release notes do not provide an update on issue 152318091.