Spend controls for any agent tool surface

Paybond's recommended default when you have no agent framework SDK — or when you call Claude/Gemini tool-use, a queue worker, or a custom orchestrator directly. One paybond.instrument() call wraps { name, execute } tools with spend verify before side effects and auto-evidence after success.

Adapter reference: /docs/kit/agent-agnostic.

• Any { name, execute } surface

  Wrap Claude tool-use, Gemini function calls, queue workers, or custom orchestrators.

• spend verify before execute

  createPaybondGenericAgentConfig authorizes operation and amount before side effects.

• Auto-evidence

  Wrapped execute finalizes spend and submits signed evidence after tool success.

• TypeScript and Python

  Same generic path via paybond.instrument() / paybond.agent() on npm and pip.

Why Paybond (not just custom checks)?

Host or model approvals do not enforce a spend limit, a per-operation permission check (capability token), or a signed completion receipt tied to a spend agreement (intent).

How it works

3-minute quickstart

Smoke the generic adapter sandbox contract:

paybond login
paybond agent demo generic smoke \
  --operation paid-tool \
  --requested-spend-cents 100 \
  --evidence-preset cost_and_completion \
  --format table

paybond login
paybond agent demo generic smoke \
  --operation paid-tool \
  --requested-spend-cents 100 \
  --evidence-preset cost_and_completion \
  --format table

When the smoke succeeds you should see:

• ✓ Spend approved
• ✓ Tool completed
• ✓ Evidence verified (cost_and_completion)

What success looks like

Scaffold

paybond init agent-middleware --framework generic --out paybond-agent.ts
paybond policy init --preset travel --out paybond.policy.yaml

paybond init agent-middleware --framework generic --out paybond-agent.ts
paybond policy init --preset travel --out paybond.policy.yaml

Validate before deploy:

paybond policy validate-tools --file paybond.policy.yaml --local-only

paybond policy validate-tools --file paybond.policy.yaml --local-only

Wire middleware

import { Paybond } from "@paybond/kit";

const paybond = await Paybond.open({ apiKey: process.env.PAYBOND_API_KEY! });

const { tools, run } = await paybond.agent({
  policy: "travel",
  tools: {
    "travel.book_hotel": bookHotel,
    searchWeb: searchWeb,
  },
});

// Your orchestrator calls tools with PaybondGenericToolCall envelopes:
const bookHotelTool = tools.find((t) => t.name === "travel.book_hotel")!;
const result = await bookHotelTool.execute({
  toolName: "travel.book_hotel",
  toolCallId: "call-1",
  arguments: { city: "Lisbon", estimatedPriceCents: 18_700 },
});

import { Paybond } from "@paybond/kit";

const paybond = await Paybond.open({ apiKey: process.env.PAYBOND_API_KEY! });

const { tools, run } = await paybond.agent({
  policy: "travel",
  tools: {
    "travel.book_hotel": bookHotel,
    searchWeb: searchWeb,
  },
});

// Your orchestrator calls tools with PaybondGenericToolCall envelopes:
const bookHotelTool = tools.find((t) => t.name === "travel.book_hotel")!;
const result = await bookHotelTool.execute({
  toolName: "travel.book_hotel",
  toolCallId: "call-1",
  arguments: { city: "Lisbon", estimatedPriceCents: 18_700 },
});

Claude / Gemini tool-use without a framework SDK

Map model function calls to Paybond-wrapped handlers:

1. Parse the model's tool call (name, arguments, and call id).
2. Find the matching entry in instrumented.tools.
3. Call execute with the Paybond envelope — authorization and evidence run automatically.

For the Claude Agent SDK specifically, use the Claude Agents adapter guide.

Production: omit sandbox defaults, use deferred bind, then instrumented.bind({ intentId, capabilityToken }) per session. Lazy binding: pass context: () => activeRequest.paybond on instrument().

Production checklist

Works with

Ready to test?

Related guides

• Agent middleware — registry, interceptor, evidence
• Express and Fastify agent routes — HTTP servers wrapping instrument()
• Mastra spend controls — native Mastra adapter
• Protect Stripe payments from agents — payment tool example

Developer reference: /docs/kit/agent-agnostic.