OneAgent for VS Code 0.5.3 pre-release
OneAgent is an agent-first VS Code workbench that lets the authoritative Codex app-server inspect and edit local files, run commands and tests, operate tools, request input or approvals, and resume durable threads.
Version 0.5.3 is the Windows-first Marketplace pre-release. It uses OneAgent Identity and an explicit, tenant-entitled installation flow for the release-manifest-pinned OneAgent Host; passes the verified installer path to PowerShell without command-line parsing ambiguity; keeps bounded incremental Webview streaming; grounds file and folder attachments through exact local paths; and presents tenant-safe Fast, Balanced and Deep model presets. Balanced is the default and all OneAgent presets use the Standard service tier. No OpenAI API key is stored in the extension or OneAgent Home.
Preview availability is currently limited to invited Ampacs pilot users on Windows 11 with VS Code Stable. The 0.5.x pilot Host is pinned to the exact release version and SHA-256 but is not yet Authenticode signed, so Windows or endpoint-security warnings may occur. The extension fails closed when the exact pilot Host or tenant entitlement is unavailable.
Work locally with a governed company agent
- Ask OneAgent to inspect a repository, edit files, run commands and tests, and
operate local developer tools.
- Follow live progress without filling the task with raw command output. On
completion,
Worked for <duration> stays available above the final reply.
- Attach files, images, the current editor selection, or a folder path. Mention
workspace files and installed Skills with
@.
- Open file references in the editor, review every changed file in native VS
Code diffs, or undo the turn when its snapshot is still safe.
- Choose Ask for approval, Workspace, or Full access. Workspace uses Codex's
native
on-request + workspace-write policy; OneAgent does not add a second
approval engine.

Search and resume local tasks without leaving the OneAgent panel:

Use Default or Plan mode with tenant-approved Fast, Balanced, and Deep presets:

Requirements
- Windows 11 and VS Code Stable
1.105.0 or newer for the 0.5.x pilot.
- An invited OneAgent company account and an entitled tenant profile.
- The OneAgent Host that matches this extension release. After sign-in,
Marketplace
0.5.3 offers Install OneAgent Host when it is missing;
download, digest verification and UAC start only after the user chooses it.
The invited 0.5.x pilot uses the exact SHA-256-pinned unsigned Host;
Authenticode signing is mandatory beginning with 0.6.0 stable.
- A trusted local filesystem workspace. Virtual and untrusted workspaces do not
start the Agent runtime.
After installing the extension, open the OneAgent Activity Bar view, choose
Sign in to OneAgent, and finish the PKCE login in your browser. The returned
tenant profile selects the isolated local Agent Home and Gateway runtime. If
the Host is missing, choose Install OneAgent Host, review the exact release
and accept Windows UAC. Login alone never installs native software.
Runtime boundary
VS Code
-> OneAgent extension and thin protocol adapter
-> OneAgent Host over process-bound local transport
-> validate Tenant Profile, user allowlist, Agent Bundle and release mode
-> select tenant/user profile and isolated OneAgent Home
-> start the pinned codex app-server with CODEX_HOME=<profile>/agent-home
-> keep short-lived Gateway credentials in memory
-> codex app-server
-> authoritative thread, turn, reasoning, tools, approvals and file changes
-> local PowerShell, Git, filesystem, build, test and application operations
-> OneAgent Gateway by default, or an explicit Codex-account development fallback
-> OneAgent Gateway
-> token-bound tenant/user/device identity
-> model entitlement, request limits and metadata-only audit
-> OpenAI Responses API using server-held credentials
The extension and Host do not add a second planner, semantic router, tool loop, transcript or ordinary local approval layer.
Ampacs development tenant
The bundled development fixture activates:
tenant: ampacs
user: <configured-development-user>
profile_key: <opaque-profile-key>
OneAgent Home: %LOCALAPPDATA%\OneAgent\Agent\profiles\<profile_key>\agent-home
The Host validates the user allowlist before launching app-server. Different tenant/user pairs receive different opaque profile keys and cannot share thread, SQLite, cache, receipt or diagnostic roots.
Unsigned Tenant Profiles are accepted only when oneagent.environment=development. Staging and production require signed profiles, a native Host and a promoted release digest. Normal releases also require an allowed Authenticode signer; only the 0.5.x Marketplace preview for tenant ampacs may use the explicit hash-pinned unsigned Host exception.
oneagent.authProvider defaults to oneagent. Set it to codex only when intentionally testing the local Codex-account fallback; staging and production always enforce OneAgent Identity regardless of that setting.
Implemented experience
- Searchable and resumable threads, sticky editable title, new-thread and settings actions.
- Streaming commentary, reasoning summaries, plans, commands, output, tools, file changes and final replies.
- Frame-batched incremental token rendering without rebuilding historical turns; collapsed command output is mounted only when opened and retained output is bounded to the latest 256 KB per activity.
- Collapsed
Worked for <duration> activity before the final reply with nested commands.
- Safe Markdown, code-style tables and clickable file references.
- File, folder-path, current-selection and image attachments.
- Grouped
@ Files and Skills suggestions.
- Agent/Plan, model, reasoning effort and service-tier selection.
- OneAgent production presets: Fast (
gpt-5.6-luna, high), Balanced (gpt-5.6-terra, medium, default), and Deep (gpt-5.6-terra, high); Standard service tier for all three.
- Refined dark OneAgent assets for the Activity Bar, Webview welcome state and packaged extension icon.
- Codex-native request-input and approval flows with Ask first, Workspace and Full access modes.
- Turn-level change summaries, native VS Code diff review and SHA-guarded Undo.
- Host-supervised app-server, isolated OneAgent Home, Tenant Profile/Bundle verification and crash propagation.
- PKCE OneAgent Identity client with SecretStorage-backed refresh sessions.
- Responses-compatible OneAgent Gateway with JWT verification, tenant/user/model entitlement, request-size limits, rate buckets, streaming pass-through and metadata-only audit.
- Windows Node SEA build for
oneagent-agent-host.exe; production signing occurs after SEA injection.
Build and verify
Set-Location <path-to-one-agent-vscode>
pnpm install --frozen-lockfile
pnpm run check
pnpm run smoke:agent-host
pnpm run build:native-host
pnpm run smoke:native-host
pnpm run package
The Host smoke tests use a disposable data root and verify the app-server reports the Host-selected isolated CODEX_HOME. They do not copy or print the user's normal Codex credentials.
Validate in VS Code
Install the exact pre-release candidate:
code --install-extension .\dist\oneagent-vscode-0.5.3.vsix --force
Then:
- Run
Developer: Reload Window.
- Open the OneAgent Activity Bar icon.
- Confirm the account action says
Sign in to OneAgent and opens https://identity.one-agent.ai.
- Sign in with an Ampacs-authorized OneAgent user. If the Host is missing,
choose Install OneAgent Host and accept Windows UAC.
- Confirm the returned Tenant Profile selects the isolated Ampacs OneAgent
Home and Gateway runtime.
- Run a read-only repository question, Plan mode, a disposable file edit/test, Review and Undo.
- Confirm logs show
OneAgent Host ready, the Ampacs tenant and a path under %LOCALAPPDATA%\OneAgent\Agent\profiles\<opaque-profile-key>.
Privacy, support and security
The source contracts, OneAgent Identity, signed production Tenant Profile and
Agent Bundle, Gateway, shared quota state and canonical production ingress are
implemented and deployed. The 0.5.3 pre-release adds an explicit, entitled
Host bootstrap flow backed by a private immutable artifact and exact digest
verification. Stable production promotion still requires the OneAgent Windows
code-signing certificate, promoted Host signer thumbprint/digest, signed
update/rollback acceptance, Ampacs pilot evidence and a second-tenant security
proof.
Marketplace builds default to oneagent.environment=production. The extension intentionally fails closed when the signed Host trust artifacts are absent.