feat: filter /switch-model to show only authenticated models

[singbong]

Problem

Currently, the /switch-model command displays all available models from model_candidates configuration, regardless of whether they are connected via auth login or not.

This causes confusion and potential issues:

1. Users may try to use models that aren't connected/authenticated
2. No indication of which models are actually available in current session
3. Security/privacy concern: showing models from different providers

Solution

Add authentication-aware filtering to /switch-model command to only show and allow switching to models that are connected/authenticated in the current OpenCode session.

Implementation Plan

1. Add OpenCode client API call

   • Use OpenCode SDK to get connected providers/models
   • Filter model_candidates based on availability

2. Update /switch-model template

   • Show indicator for models that are connected/authenticated
   • Display warning for models that are not available
   • Prevent switching to unavailable models

3. Add utility functions

   • getAvailableModels(agentName: string): Filter candidates by availability
   • filterAvailableModels(candidates: string[]): Get only available models from list

Usage

/switch-model sisyphus
# Shows only models that are connected/authenticated
# Example output:
# sisyphus (✓ 2 models available)
#   1. zai-coding-plan/glm-4.7 (active)
#   2. google/antigravity-claude-opus-4-6-thinking (connected)
#   3. cursor-acp/gpt-5.2 (not connected) ⚠

Breaking Changes

None. This adds filtering only; existing functionality remains unchanged.

Technical Notes

• Need to check OpenCode SDK for authentication/status APIs
• May need to use getConnectedProviders() or similar
• Consider caching availability status for performance

---

Summary by cubic

Add session-scoped model switching with a new /switch-model command and runtime overrides, so agents can switch to valid, configured models without touching config files.

• New Features

  • Added /switch-model command: list current assignments, show candidates per agent, and switch when the model is in that agent’s model_candidates.
  • Runtime model switcher state: getActiveModel, setActiveModel, getCandidates, getCurrentModelInfo.
  • Integrated overrides into Sisyphus, Hephaestus, and Atlas; they auto-use the active session model.
  • Config: added model_candidates to agent overrides; JSON schema updated; backward compatible.
  • Included unit tests for the model switcher.

• Dependencies

  • Bumped oh-my-opencode platform binaries to 3.5.2 in bun.lock.
  • Updated schema build to use Zod 4’s toJSONSchema.

^{Written for commit 530a571. Summary will update on new commits.}

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[cubic-dev-ai]

1 issue found across 25 files

Confidence score: 4/5

• This PR looks safe to merge, with the main risk coming from test reliability rather than production behavior.
• Shared mutable state in src/features/model-switcher/model-switcher.test.ts could cause flaky or order-dependent tests if run in parallel or with other suites.
• Pay close attention to src/features/model-switcher/model-switcher.test.ts - shared mutable state without isolation or cleanup.

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="src/features/model-switcher/model-switcher.test.ts">

<violation number="1" location="src/features/model-switcher/model-switcher.test.ts:1">
P2: Shared mutable state in tests without isolation or cleanup mechanism</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: Shared mutable state in tests without isolation or cleanup mechanism

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/features/model-switcher/model-switcher.test.ts:

<comment>Shared mutable state in tests without isolation or cleanup mechanism</comment>

<file context>
@@ -0,0 +1,169 @@
+import { describe, expect, test } from "bun:test"
+import type { AgentOverrides } from "../../agents/types"
+
+import {
+  getCurrentModelInfo,
+  getCandidates,
+  getActiveModel,
+  setActiveModel,
+  loadCandidates,
</file context>