docs: update model selection compatibility

docs/antigravity.md

@@ -75,3 +75,28 @@ agents:
 
 - **No streaming**: `agy -p` returns the full response at once; the adapter sends it as a single `agent_message_chunk` notification.
 - **Cancel is a no-op**: `agy -p` runs to completion; `session/cancel` acknowledges but cannot interrupt.
+
+## Model Selection
+
+The Discord `/models` dropdown is supported. `agy-acp` returns model
+`configOptions` when a session is created or loaded. It fetches the available
+models from `agy models` and caches a successful result. If the live fetch fails,
+the adapter uses the cache and then falls back to this static list when no cache
+is available:
+
+- Gemini 3.5 Flash (Medium)
+- Gemini 3.5 Flash (High)
+- Gemini 3.5 Flash (Low)
+- Gemini 3.1 Pro (Low)
+- Gemini 3.1 Pro (High)
+
+When a user selects a model with `/models`, OpenAB sends
+`session/set_config_option`. `agy-acp` stores the selected model for that session
+and adds `--model <model_id>` to subsequent `agy` invocations.
+
+To select a default model for every new session, set `default_config_options`:
+
+```toml
+[pool]
+default_config_options = { model = "Gemini 3.5 Flash (Medium)" }
+```

docs/devin.md

@@ -105,7 +105,9 @@ default_config_options = { model = "swe-1-6" }
 
 Available model values include: `adaptive`, `swe-1-6`, `swe-1-6-fast`, `claude-opus-4-8-medium`,
 `glm-5-2`, `gpt-5-5-medium`, `kimi-k2-7`, and many more. The full list is reported by the
-agent at session creation and visible via the Discord `/model` slash command.
+agent as ACP `configOptions` at session creation, making it available in the Discord `/models`
+dropdown once a session is active. This behavior is based on ACP client evidence; a live OpenAB
+session capture is still pending.
 
 > **Note:** The `--model` flag and `DEVIN_MODEL` env var are **ignored** in ACP mode.
 > Use `default_config_options` instead.

docs/gemini.md

@@ -2,6 +2,13 @@
 
 Gemini CLI supports ACP natively via the `--acp` flag — no adapter needed.
 
+> **Migration notice:** Since June 18, 2026, Gemini CLI no longer serves Google AI
+> Pro, Google AI Ultra, or free-tier individual accounts. Google recommends
+> migrating those users to Antigravity CLI. Enterprise users with Gemini Code
+> Assist licenses and API-key authentication remain supported. See Google's
+> [transition announcement](https://github.com/google-gemini/gemini-cli/discussions/27274)
+> and [June 18 update](https://github.com/google-gemini/gemini-cli/discussions/28017).
+
 ## Docker Image
 
 ```bash
@@ -58,7 +65,12 @@ env = { GEMINI_API_KEY = "${GEMINI_API_KEY}" }
 
 ## Authentication
 
-Gemini supports Google OAuth or an API key:
+Gemini CLI authentication depends on the account type:
 
-- **API key**: Set `GEMINI_API_KEY` environment variable
-- **OAuth**: Run Google OAuth flow inside the pod
+- **API key**: Set the `GEMINI_API_KEY` environment variable.
+- **Enterprise or Google Cloud OAuth**: Run the Google OAuth flow inside the pod
+  using an organizational account with supported Gemini Code Assist or Google
+  Cloud access.
+- **Individual OAuth**: Google AI Pro, Google AI Ultra, and free-tier individual
+  accounts are no longer served by Gemini CLI. Migrate these users to
+  Antigravity CLI.

docs/slack.md

@@ -114,15 +114,19 @@ The bot will reply in a thread. After that, just type in the thread — no @ment
 
 openab supports `/models`, `/agents`, and `/cancel` on **Discord**, but **not on Slack**. If you previously configured these commands in your Slack app's **Slash Commands** page, you can safely delete them — the Slack adapter ignores both `slash_commands` and `interactive` envelope types.
 
-The root cause is a combination of three Slack-specific platform constraints, none of which is fixable from openab's side:
+The root cause is a combination of two Slack-specific platform constraints, neither of which is fixable from openab's side:
 
 1. **Slack blocks third-party slash commands inside threads.** Invoking `/models` from a thread's reply composer returns the Slack error `"/models is not supported in threads. Sorry!"`. This is enforced by the Slack client itself, not by any app setting — enabling Interactivity, Socket Mode, or reinstalling the app does not bypass it. Slack's built-in commands (`/remind`, `/shrug`, etc.) get special treatment that custom apps cannot.
 
 2. **Channel-level slash command payloads have no thread context.** If the user types `/models` in the channel's main composer instead of a thread, Slack delivers the command but the payload carries no `thread_ts`. Since openab keys each ACP session by thread (`slack:<thread_ts>` or `slack:<trigger_ts>`), the command cannot be routed to the right session. Sessions are never keyed by `channel_id` alone, so there's no workaround on the adapter side.
 
-3. **Most ACP agents don't expose a model-switch surface.** Even when routing succeeded, `/models` reads the session's `configOptions` from the ACP `initialize` response. Only `kiro-cli` emits these in the expected format (via its `models`/`modes` fallback). `claude-code`, `codex`, `gemini`, `cursor-agent`, and `opencode` do not, so the menu would be empty for those backends — the user would see `"⚠️ No model options available"` with no recourse.
+Backend model-selection support also varies; see the current
+[slash-command compatibility table](slash-commands.md#models-and-agents). This
+does not change Slack support: the two routing constraints above prevent the
+menu from reaching the correct session even when a backend emits model
+`configOptions`.
 
-On Discord, none of these apply: slash commands work in thread-channels, the channel ID *is* the thread key, and users typically stay within a single agent per deployment anyway.
+On Discord, neither constraint applies: slash commands work in thread-channels, the channel ID *is* the thread key, and users typically stay within a single agent per deployment anyway.
 
 ### If you need to switch models or agents with a Slack deployment
 

docs/slash-commands.md

@@ -40,7 +40,10 @@ When the user picks an option, OpenAB sends `session/set_config_option` to the A
 | kiro-cli | ✅ Returns available models via `models` fallback | ✅ Returns modes (`kiro_default`, `kiro_planner`) via `modes` fallback |
 | claude-code | ❌ No `configOptions` emitted | ❌ |
 | codex | ❌ | ❌ |
-| gemini | ❌ | ❌ |
+| gemini | ❌ No `configOptions` emitted; see [Gemini CLI account migration guidance](gemini.md) | ❌ |
+| antigravity | ✅ Returns available models via `configOptions`; `agy-acp` fetches them from `agy models`, with cache and static fallback | ❌ |
+| opencode | ✅ Emits model `configOptions` at session creation in OpenCode 1.17.9 (source-confirmed; live OpenAB session capture pending) | ❌ |
+| devin | ✅ Emits model `configOptions` at session creation (ACP client evidence; live OpenAB session capture pending) | ❌ |
 | cursor-agent | ❌ (tracking: #493) | ❌ |
 | copilot | ❌ (tracking: #496) | ❌ |