Security & Privacy

Caliper is a CLI tool that runs in your local environment. Here's exactly what stays local, what leaves your machine, and when.

What runs locally

These operations never make network calls:

• Convention checks (caliper check) — compiled grep patterns, AST analysis, and file structure checks run entirely in your shell. No code is transmitted. No API key required.
• Config scaffolding (caliper init) — reads your project structure and writes .caliper/ files locally. If ANTHROPIC_API_KEY is set, init also runs caliper refresh to compile your CLAUDE.md into checks (this calls the Anthropic API — see below). Without an API key, init still works but skips convention compilation.
• State management — pipeline state, trace files, and review history are stored in /tmp/caliper/ on your machine.

What calls the Anthropic API

These operations send code to Anthropic's API for AI analysis:

Operation	What is sent	When
caliper refresh	CLAUDE.md file contents	One-time setup (rerun when conventions change)
caliper review	Staged diff + function context around changes	Each local AI review
caliper <pr>	PR diff + function context + file metadata	Each PR review

What is NOT sent: Your full codebase, git history, environment variables, secrets, or .env files. Only the diff and surrounding function context for changed files are transmitted.

Anthropic's data retention policy applies. API inputs are not used to train models.

What calls the GitHub API

These operations use the GitHub API via the gh CLI:

Operation	API calls
caliper <pr>	Fetch PR metadata, diff, and existing comments
Posting findings	Create review comments on the PR
--ci mode	Delete stale comments from previous runs

The gh CLI uses your existing GitHub authentication. Caliper does not store or manage GitHub tokens directly.

Credentials

Credential	Used by	Storage
ANTHROPIC_API_KEY	AI review + convention compilation	Your shell environment — never written to config files
gh auth	PR fetching + comment posting	Managed by GitHub CLI (gh auth login)

Caliper never writes credentials to .caliper/ config files, state files, or trace logs.

Air-gapped / offline mode

If you cannot send code to external APIs, you can still use convention enforcement:

1. Run caliper refresh once in an environment where the API key is available
2. Commit the generated .caliper/checks.js to your repo
3. Run caliper check anywhere — it executes the compiled checks with zero network calls

This gives you deterministic convention enforcement on every agent turn with no external dependencies at runtime.

Licensing

Caliper is proprietary software — see the LICENSE file in the repository root. The @caliperai/caliper npm package is publicly available on npm.

Data flow summary

Your repo
  │
  ├─ caliper check             → Local only (grep/AST)
  │
  ├─ caliper refresh           → CLAUDE.md contents → Anthropic API
  │                              → .caliper/checks.js written locally
  │
  ├─ caliper review            → Staged diff → Anthropic API
  │                              → Findings displayed in terminal
  │
  └─ caliper <pr>              → PR diff → Anthropic API
                                → PR metadata ← GitHub API
                                → Review comments → GitHub API