API Circle Studio

Git-backed API workspace with mocks, plans, and MCP — natively in VS Code.

Edit your API Circle workspace inside VS Code. The same .apicircle/ workspace directory you commit to Git, edit in the API Circle Desktop App, or open in the API Circle Web App — one repo, three surfaces, byte-identical commits.

Why

VS Code is where the same engineers who use API Circle already live with Git. Editing your API workspace inline removes the context switch from editor → API client → back. Because the canonical workspace lives in your repo's .apicircle/ folder, VS Code's native Git extension tracks every change — no separate sync, no separate auth, no separate review surface.

Features

Workspace & navigation

• Activity Bar icon opens the API Circle sidebar with 9 views: Workspace, Editor, Environment, Execution, Mock, History, Snapshots, MCP, and Link Workspaces.
• Workspace discovery auto-detects .apicircle/registry.json in your open folders and Git-backed .apicircle/ directories.
• Workspace switcher — switch between discovered workspaces via the sidebar or APICircle: Switch Workspace.
• apicircle: virtual filesystem — requests, environments, plans, mocks, folders, and responses project as YAML documents in real VS Code text editors. Human-readable tab titles, folder paths in tooltips, identity preserved across renames and moves.

Request authoring & execution

• Request templates — six starter shapes via APICircle: New Request from Template… (Simple GET, JSON POST, Bearer-protected GET, Paginated GET, GraphQL query, REST CRUD scaffold).
• CodeLens helpers — ▶ Send, ✚ Add section…, ⤵ New from template… above each request YAML. In-flight requests swap to ⏳ Sending… · ✖ Cancel.
• All 17 auth types — none, bearer, basic, api-key, digest, NTLM, Hawk, AWS Signature v4, JWT bearer, and all OAuth 2.0 grants (Authorization Code, PKCE, Client Credentials, Password, Implicit, Device Code, private_key_jwt, token refresh).
• Folder-wise auth — set auth on a folder; child requests inherit via ◆ Inherits from <Folder> CodeLens.
• URL-as-source-of-truth — query parameters and path placeholders sync from the URL into structured sections on save.
• Response viewer as a virtual .run.yaml opened side-by-side — appears instantly on ▶ Send, resolves in place.
• Cancel in-flight requests via status bar, Esc, or the ✖ Cancel CodeLens.
• Pre-send diagnostics surfacing in the Problems panel.

Mock servers

• Mock endpoint authoring in YAML — *.endpoint.yaml with field-level ◆ CodeLens editors on method, status, headers, body type, response rules, and multipliers.
• Validation rules — 🛡 Add validation rule with kind-aware pickers for headers, query params, cookies, and path params.
• Request schema editing on all surfaces (VS Code YAML, Web/Desktop editor, and MCP).
• In-process mock server lifecycle — start, stop, and manage mocks from the sidebar.

MCP integration

• 94-tool MCP catalog for AI clients — Claude Desktop, Claude Code, Codex, Cursor, Copilot, Windsurf, Zed, Continue, Cline.
• One-click Copilot Chat install — writes .vscode/mcp.json idempotently.
• Per-client config snippets — copy or direct-install MCP configuration.
• Curated prompts — 19 starter prompts across 7 categories in the MCP sidebar.

Secret vault

• Passphrase-protected AES-GCM encrypted secret storage.
• Auto-lock by inactivity, clipboard auto-clear.
• Encrypted environment variable reveal via apicircle.openVaultEntry.

Link Workspaces

• Publish releases — tag, deprecate, and withdraw versions via releases.yaml CodeLens.
• Consume linked workspaces — link private repos or marketplace results, pin versions, manage scopes and required secrets.
• Three-way update review — preview incoming changes, accept source or keep yours per-field.

The three-surface principle

API Circle Studio's Web App, Desktop App, and VS Code extension are peer clients of the same canonical format:

<your-repo>/.apicircle/registry.json                     # workspace index
<your-repo>/.apicircle/workspace-<id>/workspace.json      # per-workspace doc

Edit on any surface → commit → push → pull elsewhere → continue. No translation, no dialect, no per-surface fork. Device-local data (history, secrets, sessions) stays per-machine in each surface's managed storage.

Installation

Install from the Visual Studio Marketplace or the Open VSX Registry:

Extensions view → search API Circle Studio → Install

Or build the .vsix locally:

1. Clone the repo.
2. pnpm install && pnpm --filter apicircle-vscode build
3. cd apps/vscode && pnpm exec vsce package --no-dependencies
4. Install via Extensions: Install from VSIX… in the command palette.

See docs/vscode-extension-install-publish.md for the full guide.

License

See repo-root LICENSE.