kiso 0.49.0

kiso 0.49.0

Subagents that do not block, and a tool surface that costs less. A delegated reader no longer holds your session for minutes; a writer works in its own isolated copy and you adopt its patch with one command; a child agent runs on the model you picked. The first request is 282 tokens smaller than 0.48.0's.

• The bounded join (ADR-0058 Amendment 13): explorers and reviewers always run in the background under a turn budget, and their result arrives as a task notice.
• Writers (Amendment 14): a background implementer in an isolated workspace; the parent collects its patch and adopts it with kiso apply-patch, with a crash-honest record of the adoption. A writer's turn budget defaults to 128 requests.
• A child follows your model (the child contract): the task, then subagents.model, then the conversation's current profile, then the environment. The delegation config now reaches the subagent extension before it loads.
• edit_file takes oldText / newText (ADR-0061), so the model no longer writes search and replace the wrong way round.
• The tool descriptions say each fact once: delegate −691 B, edit_file −77 B, shell −75 B on the bench's profile.
• A spent chain budget is said everywhere: to the model on a subagent group's end too, and once to you as a chain budget spent row.
• The unknown-window fallback is 200K again.

For hosts

• Action required: none for a host that passes its delegation config through the CLI's path. A host that built the subagent extension itself and read its config at load time should make sure the config exists before the extension loads.
• Observable: reader delegations return at once and report through a task notice; writer delegations return a handoff and the patch is adopted with apply-patch; a child's model follows the precedence above; edit_file's parameters are oldText / newText; the tool descriptions are shorter; a spent chain budget reaches the model on a group's end and the person once; the unknown-window fallback is 200K. 8 of the 17 packages differ beyond package.json (kiso-ask-ext, kiso-code, kiso-runtime, kiso-skills-ext, kiso-subagent-ext, kiso-tools-node, kiso-tui, kiso-tui-cells); kiso-core is byte-identical to 0.48.0.
• New optional: onBudgetSpent on useTasks; writer delegation and apply-patch; subagents.model (per role); writerMaxTurns.

The release gate — T3 and T5 paired against 0.48.0 (16 pairs each, both PASS, the first request 282 tokens smaller in 32/32 pairs), the chain budget's two-round test, the writers' adoption path (4/4), the kill -9 demo (2/2), the full check and a live sol session — is summarised in the release report.