[AmoabaKelvin]

	Files	Added	Deleted	Net
Test	3	$\color{#1a7f37}{\Huge{\mathbf{+}}}$​198	$\color{#cf222e}{\Huge{\mathbf{−}}}$​2	$\color{#1a7f37}{\Huge{\mathbf{+}}}$​196
Prod	11	$\color{#1a7f37}{\Huge{\mathbf{+}}}$​149	$\color{#cf222e}{\Huge{\mathbf{−}}}$​48	$\color{#1a7f37}{\Huge{\mathbf{+}}}$​101

ELI5

Before a chat sends its first message, Orca fills the model picker by asking the agent which models it has. OpenCode 2.x has no command that answers that correctly, so the first OpenCode chat on a 2.x install had an empty picker. Now Orca opens a chat session with OpenCode in the background, reads the models that session offers, and deletes it.

What Changed

Before. With opencode on 2.x, Orca ran opencode models --verbose, which every 2.x release rejects. The first chat of an account had no model list until its first message.

After. On 2.x the picker lists the models before the first message, and nothing is left in the user's OpenCode history. The list is saved and reused like every agent's. On 2.x it is refreshed when a chat asks and the saved list is more than 10 minutes old; the background refreshes at app start and after a setting change skip it, because they have no chat folder to open a session in. 1.x still uses models --verbose, unchanged.

Mechanism. OpenCode's listing setting now says which releases its listing command covers (1.x) and that other releases list through a session. The model list probe gained that session path: it checks that the agent can delete a session (sessionCapabilities.delete), opens one with session/new in the folder of the chat that asked, reads its models with the same code a running chat uses, and deletes it with session/delete. An agent that cannot delete a session is not asked. The model list service now hands the asking chat's folder to the probe. Registrations mark a listing that runs in a chat's folder, and a startup or settings refresh, which has no chat, never runs it; a read without a folder skips it without counting as a failure. So a picker never waits on a listing that cannot answer it.

Why

• 2.x's own listing commands are not safe. Every 2.x release rejects --verbose. opencode models and opencode api model.list answer empty from a fresh start on 2.0.14 to 2.0.26, and on 2.0.28 left out a provider that loaded 300 ms late. Orca lets a newer list replace an older one, so a short list would hide working models. Upstream: v2: opencode models --refresh no longer recognized (flag removed from models command) anomalyco/opencode#53682, cli: opencode models prints empty list with exit 0 on a cold server anomalyco/opencode#53724 and fix(server): await catalog readiness for model and provider reads anomalyco/opencode#36117, all open.
• A new session offers exactly what a chat offers, because it is how a chat starts, and OpenCode waits for its providers before answering it.
• Deleting it keeps the user's history clean. 2.0.14 and 2.0.29 both delete a session over the chat protocol. 1.x answers "method not found", which is one reason it keeps its command.
• It opens the session in the chat's folder, as bb (get-bb/bb) does. OpenCode 2 records a project for every folder a session opens in. In the home folder, the throwaway session left a home-folder project in OpenCode's own project list; in the chat's folder it records the project the chat creates anyway.

Linked Issue

Part of #19581. The next PR, #28424, makes the OpenCode 2 launcher entry open as a chat and lists its models the same way.

Visual Proof

N/A: the picker looks the same; it now has models before the first message. Testing gives the counts.

Testing

• New tests, each failing on the previous code: on 2.x the probe opens a session in the asking chat's folder, reads its models and deletes it, with no listing command; it opens no session on a release that cannot delete one, nor without a chat folder; a startup refresh that skips is not held, and the next read lists in its chat's folder.

• Real OpenCode, isolated folders: on 2.0.14 and 2.0.29 a new session reported 71 and 11 models, and after session/delete OpenCode's store held no session and no file was written in the folder.

• Real app (hidden dev builds, macOS arm64, fresh profiles, isolated OpenCode folders):

  • opencode on 2.0.29: the first chat lists 11 models before any message, and OpenCode's store holds no session afterwards.
  • OpenCode 1.19.0: the first chat lists 11 models before any message through models --verbose, and no session is created.
  • A second chat reuses the saved list without starting OpenCode again.
  • OpenCode's project list afterwards holds only the chat's folder; before this change it also held the home folder.
  • After a restart with the saved list over 10 minutes old, the startup refresh ran nothing for OpenCode 2 (Orca's trace shows no OpenCode 2 refresh until a chat asked), and a new OpenCode 2 chat opened right after listed 11 models.

• pnpm lint, pnpm tc, the three audits, check:code-quality:changed, check:react-doctor:changed and check:zustand-selector-fanout pass on the head. 56 dependent test files pass (563 tests)..

• I manually tested these changes locally

• Automated tests added/updated, or explained why not below

Review

Agent skill upstream boundary

• Not applicable, or this change copies or mechanically translates no upstream skill-installer source, tests, fixtures, registry entries, path tables, comments, or documentation.

Notes

• Not tested: Windows, Linux and a signed-in OpenCode account.
• If the delete never arrives (OpenCode exits, the listing times out, or Orca quits in the second between), one empty conversation is left in OpenCode's history, in the chat's folder. The model list is still saved.
• Found while testing, not caused by this PR: OpenCode's free models now refuse requests from other apps ("OpenCode's free tier can only be used from within OpenCode"), on 1.19.0 and 2.0.29 alike. Orca's OpenCode chats show it as a sign-in prompt. I could not test a signed-in account.
• Per-project model lists, unchanged from main: Orca keeps one model list per account, while OpenCode can add models in a project's own config. A list read in project A is shown in project B until a chat in B reports its own. Main already does this through running chats' lists. bb keeps OpenCode's list per project folder; doing that here changes the shared model list for every agent and every screen that reads it, so it is left for its own PR.
• Backwards compatibility: no setting, stored data or wire change.

Checklist

• This PR is small and focused
• I explained what changed and why (ELI5, the user-facing before/after, the mechanism, and why over the alternatives)
• Before/after screenshots or videos attached for UI changes, or N/A with reason
• Self-reviewed for correctness, security, and performance
• Cross-platform, SSH/remote, and path/shortcut impact considered (or N/A)
• pnpm lint, pnpm typecheck, pnpm test, and pnpm build pass (or CI will cover; local preferred)

[AmoabaKelvin]

Folded into #28424, which now carries the model list work as well as the OpenCode 2 chat, so there is one PR to review.