Guarantees you can verify.

Every CapabilityBase capability comes with contractual guarantees. Not marketing claims. Testable, versioned, enforceable promises.

Deterministic

Same input → same output, always. No randomness. No temperature. No "it usually works." Verified by automated tests on every commit.

Testable
🔒

Local First

Your data never leaves your device. No servers, no tracking, no analytics. Every capability runs entirely in your browser or local Node process.

Privacy
📋

Versioned

Semantic versioning (SemVer). Never breaking changes without a major version bump. Capability IDs are stable forever. Contracts are immutable within a version.

Stability
🧪

Tested

Every capability passes functional tests, boundary tests, and performance benchmarks. Test counts are published. Failures block release.

Quality
📚

Documented

All documentation is auto-generated from the capability manifest. One source of truth: the manifest drives docs, SDK types, and API specs.

Generated
🔀

Reusable

One implementation, consumed by Web pages, REST APIs, JavaScript SDKs, CLI tools, and AI agents via MCP. Zero duplication.

DRY
🤖

AI Ready

MCP, OpenAPI, and LangChain compatible. Drop into any agent workflow. No custom protocols. No lock-in.

Interoperable

Zero Dependencies

No npm install. No package.json bloat. Every capability is self-contained. The entire runtime fits in a single file.

Lightweight

The 7 Principles

1

Capability First

Not page first. Not API first. The capability is the atomic unit. Everything else is an interface to it.

2

One Implementation

Never duplicate logic. Web, API, SDK, CLI, and Agent all consume the same core.

3

Deterministic

Never call an LLM. Never use Math.random(). Same input must produce same output, every time.

4

Local First

If it can run in the browser, it must. No server required for any core operation.

5

Generated

Docs, APIs, SDKs, and type definitions are all generated from the capability manifest. No manual maintenance drift.

6

Stable IDs

A capability ID never changes. json.repair will always mean json.repair. URLs and contracts remain valid forever.

7

Composable

Any capability can be chained with any other. The output of one is the input of the next.