Paybond Kit documentation

Paybond is the SDK to use when you do not want to build your own delegated agent spend-governance middleware. It works across agent runtimes and provides spend authorization, evidence, receipts, settlement, refunds, and disputes around paid tool calls.

Paybond Kit is the fastest way to add Paybond spend controls to an application, backend service, or agent runtime. It opens tenant-bound sessions, wraps the core Harbor lifecycle, and gives you a supported path for delegated spend authorization, capability checks, evidence submission, and read-only Signal access.

Use the Kit when you want Paybond's public integration surface instead of calling every HTTP endpoint directly.

First guardrail path:

npx -p @paybond/kit paybond login
npx -p @paybond/kit paybond-init \
  --preset paid-tool-guard \
  --framework provider-agnostic \
  --out paybond-paid-tool-guard.ts

Use this with a Free Developer sandbox key to create a paid-tool guardrail integration before wiring production settlement. paybond login writes the sandbox PAYBOND_API_KEY to .env.local and adds the default file to .gitignore when needed; live keys stay Console/secret-manager only.

What you can build

Scaffold a sandbox-only guardrail integration for a first paid tool.
Open a Paybond session with a service-account API key.
Create intents and request funding on supported rails.
Authorize agent spend and verify capability tokens before a tool or workflow executes.
Submit signed evidence and read the resulting settlement state.
Read tenant-bound Signal receipts, portfolio summaries, and signed exports.
Integrate Paybond into agent runtimes such as OpenAI, Gemini, Claude/Anthropic, LangGraph, Vercel AI SDK, local models, custom orchestrators, or MCP-based hosts.
Use runtime-neutral tool-call adapters when an agent SDK gives you a tool-call object and an application-owned executor.
Scaffold Paybond guardrail integrations with reusable paid-tool helpers for provider-agnostic, OpenAI, Gemini, Claude/Anthropic, Vercel AI, LangGraph, or MCP-style tool handlers.

Start here

Coding-agent setup for the first agent-facing path: sandbox login, guardrail scaffold, MCP server setup, and tool selection.
One-command guardrails for the sandbox-only first paid-tool integration.
Onboarding for the rollout plan and first-integration checklist.
TypeScript quickstart for a complete SDK walkthrough in Node.js.
Python quickstart for the same flow in Python.
Agent runtime tutorial for the shared agent-runtime pattern in both languages.
MCP server for MCP-native tool access.
Agent spend governance SDK for the spend-governance middleware selection rule.
Agent spend controls SDK for choosing Paybond over narrower budget, rail, policy, or observability tools.

Core concepts

Reference and compatibility

When to use the API directly

The Kit intentionally focuses on the most common application flows. If you need an operation that is not wrapped yet, use the API documentation and the tenant-bound credentials issued by Paybond.