CodeSlicer for VS Code

CodeSlicer is local-first. The TypeScript package supplies the cockpit while the canonical Python Core is bundled as a separate process inside each platform-specific VSIX. Normal users do not install Python, pip, a virtualenv, source code, Graphify, or an executable.

Version contract

The cockpit and analyzer have intentionally independent versions. The current Windows package is valid only when this tuple agrees:

0.5.3 is the analyzer release, not the extension release. The manifest is the compatibility boundary; a mismatched extension folder, package manifest, or extensionCompatibility must be treated as an invalid installation.

Install the matching VSIX, open a trusted project, and select Review current changes. The extension uses argv-only spawning with shell: false and logs argv, cwd, stdout, stderr, and exit status. No process runs during activation.

First review in VS Code

1. Download the matching platform VSIX from the VS Code platform runtime workflow or a published release, then choose Extensions → ⋯ → Install from VSIX… in VS Code.
2. Open a trusted source workspace, select the CodeSlicer icon in the Activity Bar, and click Check readiness. It reports the project and bundled runtime before any analysis starts.
3. Select Review current changes. Choose a source on the Review tab, then use Results for risk/evidence and Tests to inspect an exact command. A test is never started until you confirm that command in a fresh modal.

The Help tab contains task-oriented guides for review, tests, Git, map, GitHub PR and Graphify. A guide only navigates and highlights the real Cockpit controls; it never starts the runtime, Git, network access or a test.

When to open Local Hub

Use CodeSlicer: Open Local Hub from the Command Palette when the browser is more convenient for a large map or a longer review. The command starts the bundled runtime only after that explicit request and opens http://127.0.0.1:8001/ by default. The server is loopback-only; it is not a publicly deployed website or a remote code-analysis backend. The same Hub can be started from the Core with impact-engine-local-api --default-project <project>. See the repository Local Hub guide.

Platform packages

VS Code selects platform-specific packages created with vsce --target. The runtime resolves in the workspace extension host, so WSL, SSH, Dev Containers, and Codespaces need the matching VSIX installed in that remote window. Unsupported hosts get a diagnostic; CodeSlicer never downloads a substitute.

Each package contains one runtime/<target>/bin/codeslicer executable. It has explicit CLI and local-api modes, avoiding a duplicate embedded Python runtime while preserving the Local Hub. The manifest carries version/platform/architecture/SHA-256 data and embedded-runtime notices/licenses; the extension verifies every declared file before execution, and an invalid checksum, missing file, or unsafe manifest path blocks the runtime.

Development and packaging

cd extensions/vscode
npm ci
npm test
# Press F5 here for an Extension Development Host.
npm run package

scripts/build_bundled_runtime.py refuses cross-platform builds. It uses PyInstaller on a native runner to package the current Core, support packs, language plugins, Tree-sitter dependencies, and private Python runtime. Install pyinstaller in the build environment. CI creates non-Windows artifacts. Inspect generated VSIX files with Expand-Archive or unzip -l.

The VSIX excludes the source repository, .venv, node_modules, caches, .impact_engine, Graphify outputs, tests, and secrets.

Large-workspace behavior

The bundled Core keeps evidence correctness ahead of a deceptively fast partial result. A changed-file candidate cannot replace the canonical graph unless it covers the complete analysis scope; otherwise the next explicit review performs and reports a full refresh. This prevents routes, callers, and tests outside the changed file from disappearing from the workspace graph.

On the Django repository at commit 60121939f6b225c7a719dd561e372e1d8e5e2c4a (6,958 files; 315,345 nodes; 316,365 edges), CodeSlicer 0.6.30 reduced the post-hygiene/quality stage from 56.9 s to 14.7 s. A repeated review of the same local diff fell from 83.1 s to 61.5 s on the benchmark Windows x64 host. Cold-run timing is storage-dependent and measured 184–235 s, so it is not a cross-machine SLA.

For large graphs, verbose hygiene annotations are kept in the local compressed sidecar .impact_engine/project_hygiene.json.gz. The main graph retains the summary and a reference; deep impact requests load the complete report only when needed. No code or graph is sent over the network.

Cockpit workflow

The webview keeps the normal path simple:

1. Review — choose working tree, staged changes, branch comparison, a local patch, or optional GitHub PR.
2. Results — risk, reasons, affected entities, and evidence.
3. Tests — recommendations; every real test requires a new modal confirmation.
4. Technologies — built-in language coverage, graph freshness, and optional-pack status.
5. History — the last local review summaries in workspace state.
6. Code — a bounded canonical CodeSlicer slice; Graphify remains an explicitly connected, separate optional engine.
7. Git — a separate branch tree with current/upstream state, remotes, recent commits, branch creation/switching, and a push preflight.

The interactive guide only switches these real tabs. It does not invoke Git, the runtime, tests, or network requests.

Broad discovery is explicit

The primary review contains only Confirmed and Likely impact. Select Show potential scope in the Results view (the extension requests codeslicer review --show-potential) to inspect a separate, collapsed safety layer: Possible low-confidence candidates, Rejected resolver relationships, and graph/coverage limitations. This layer never changes the risk score or adds tests to the recommended test plan. In CLI and MCP the same contract is explicit through --show-potential / include_potential; --full-evidence remains exclusively the complete proven impact closure.

Optional language packs

Core language coverage is bundled for offline use. Additional language packs are deliberately unavailable until CodeSlicer publishes a signed registry and verification key. The extension does not contain a guessed endpoint or a pretend download action. A future registry must provide a target-specific, versioned manifest plus SHA-256 and signature verification, atomic installation and rollback; until then the Technologies screen reports the honest offline state.

Product boundaries

The cockpit supports analysis, working-tree/compare/diff review, risk/evidence/test recommendations, confirmed test execution, selected-symbol inspect, local history, source navigation, and the canonical architecture slice. Local Hub opens only after an explicit user action and listens on loopback.

Graphify is optional and separate: CodeSlicer never downloads or installs it, and its data does not affect canonical evidence or ranking. Local Git review needs no GitHub token.

Git cockpit and GitHub access

The Git tab is intentionally explicit: it reads the local branch tree only after you select Refresh tree; create/switch branch and add-remote actions are each confirmed. Before a push you select the exact local source branch, remote, and destination branch. The extension shows ahead/behind status and blocks a likely non-fast-forward push. A second modal confirmation is required to push, and force-push is never offered.

Push uses the Git credentials already configured for your machine (Git Credential Manager or SSH). CodeSlicer does not place a token into a remote URL, shell command, Output log, or workspace settings. The optional Store GitHub token control writes it only to VS Code Secret Storage for future GitHub API functionality; today GitHub PR preparation uses explicit VS Code OAuth and read-only API calls. Publishing PR comments/checks is not implemented.