Paybond is presented publicly through four product surfaces. Each surface keeps its branded name; the subtitle is the plain-English role a first-time visitor should learn alongside the brand.
The same vocabulary is defined in code at apps/admin/lib/public-content/product-surfaces.ts and reused across the public site, docs, and llms.txt.
Surfaces at a glance
| Brand | Subtitle | One-line job | Route | Stack order |
|---|---|---|---|---|
| Kit | Developer SDK | Policy middleware and integration for agent runtimes | /kit | 1 — integrates |
| Harbor | Agent transaction engine | Signed intents, escrow, evidence evaluation, release/refund | /harbor | 2 — settles |
| Ledger | Evidence & provenance | Append-only signed history for audits and exports | /ledger | 3 — record |
| Signal | Standing & reputation | Receipts and standing derived from verified settlement | /signal | 4 — build standing |
Lifecycle
Read the stack top to bottom:
Kit integrates → Harbor settles → Ledger records → Signal builds standing
- Kit — Developer SDK: integrate your agent runtime with Paybond policy middleware, sessions, and evidence hooks. Authorization is a capability you invoke through Kit — not something the SDK performs on its own.
- Harbor — Agent transaction engine: run the signed intent lifecycle — intents, escrow, evidence evaluation, and deterministic release or refund.
- Ledger — Evidence & provenance: record an append-only, signed history for audits and exports.
- Signal — Standing & reputation: build portable receipts and standing from verified settlement.
Stack diagram
Agent runtime
│
▼
Kit
Developer SDK
│
▼
Harbor
Agent transaction engine
│
▼
Ledger
Evidence & provenance
│
▼
Signal
Standing & reputation
How this maps to runtime services
Public product surfaces describe the capabilities developers use. They don't necessarily map one-to-one to internal services, binaries, or crates. Harbor, Signal, and Ledger marketing pages describe buyer-facing jobs; Gateway remains the authenticated API front door in API documentation rather than a fifth marketing surface.
For the full platform picture, start with Paybond platform overview.