fix(agent-manager): inherit model and variant in tool sessions

[marius-kilocode]

Tool-started Agent Manager sessions currently omit model and reasoning state unless the agent supplies explicit overrides. A new session then resolves fresh defaults independently, which can send fan-out work to a recent or provider fallback model instead of the model selected for the invoking chat turn.

Prompted tasks now inherit the exact provider, model, and reasoning variant from the chronology-resolved invoking turn. The tool guidance tells agents to omit these fields by default and only provide overrides when explicitly requested. Variant-only overrides retain the inherited model, while explicit model resolution prefers the invoking provider and uses deterministic fallback ordering.

Prepared sessions without an initial prompt continue to use normal defaults.

[kilo-code-bot]

SUGGESTION: Variant-only overrides aren't echoed in the "Resolved models" summary

This filter (!params.tasks[index]?.model?.trim() || !task.model) only echoes a resolution when the agent passed an explicit model override, matching the pre-existing behavior for named-model resolution. But with this PR, a task can also carry an explicit variant-only override that changes the effective reasoning variant while inheriting the model from the invoking turn (see the select() branch a few lines above returning { ...base, model: source.model, variant }). Since params.tasks[index]?.model is empty for that case, the variant override is silently applied without appearing in the "Resolved models:" output, so the agent/user has no confirmation that the variant was actually changed (as opposed to falling back to the inherited default).

Consider also echoing when params.tasks[index]?.variant?.trim() is set, not just model.

---

Reply with @kilocode-bot fix it to have Kilo Code address this issue.

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge (non-blocking)

Overview

Severity	Count
CRITICAL	0
WARNING	0
SUGGESTION	1

Issue Details (click to expand)

SUGGESTION

File	Line	Issue
packages/opencode/src/kilocode/tool/agent-manager.ts	251	Variant-only overrides aren't echoed in the "Resolved models:" output summary, unlike explicit model overrides

Files Reviewed (7 files)

• .changeset/agent-manager-inherit-model.md - user-facing, well-scoped changeset present
• packages/kilo-docs/pages/automate/agent-manager.md - prose updated consistently with new inheritance behavior
• packages/opencode/src/kilocode/tool/agent-manager-models.ts - hint text updated, no logic change
• packages/opencode/src/kilocode/tool/agent-manager-models.txt - description text updated, no logic change
• packages/opencode/src/kilocode/tool/agent-manager.ts - 1 suggestion
• packages/opencode/src/kilocode/tool/agent-manager.txt - description text updated, no logic change
• packages/opencode/test/kilocode/agent-manager-tool.test.ts - new tests exercise real select()/execute() logic (no mocked business logic), good coverage of inherit/override/edge-case paths

Verified: source/preferred short-circuiting avoids an unnecessary defaultModel() call when the invoking turn's provider is known; the deterministic provider tie-breaker (localeCompare on providerID/model id) is correctly exercised by the new stable-tie-break test; undefined/no-user-message paths in select() degrade gracefully to normal defaults or an explicit error rather than throwing. This is a Kilo-only path (src/kilocode/tool/) with no shared-file changes, so no fork-merge hygiene concerns.

Fix these issues in Kilo Cloud

---

_{Reviewed by claude-sonnet-5 · Input: 62 · Output: 22.6K · Cached: 1.9M}

_{Review guidance: REVIEW.md from base branch main}